ir_load_llvm.c

/*
 * IR - Lightweight JIT Compilation Framework
 * (LLVM loader)
 * Copyright (C) 2022 Zend by Perforce.
 * Authors: Dmitry Stogov <dmitry@php.net>
 */

#include "ir.h"
#include "ir_builder.h"
#include "ir_private.h"

#include <llvm-c/Core.h>
#include <llvm-c/Target.h>
#include <llvm-c/BitReader.h>
#include <llvm-c/IRReader.h>

// The numbers from <LLVM/IR/Attributes.inc>
#define LLVMAttrAlwaysInline    3
#define LLVMAttrInlineHint     12
#define LLVMAttrNoInline       26

#define LLVM2IR_INLINE_MAX_HINT_BLOCKS 10
#define LLVM2IR_INLINE_MAX_HINT_COST   50
#define LLVM2IR_INLINE_MAX_BLOCKS      5
#define LLVM2IR_INLINE_MAX_COST        30

#define IR_BAD_TYPE IR_LAST_TYPE

#define BUILTIN_FUNC_1(name, ret_type, arg1_type) \
	ir_const_func(ctx, \
		ir_strl(ctx, name, strlen(name)), \
		ir_proto_1(ctx, IR_BUILTIN_FUNC, ret_type, arg1_type))
#define BUILTIN_FUNC_2(name, ret_type, arg1_type, arg2_type) \
	ir_const_func(ctx, \
		ir_strl(ctx, name, strlen(name)), \
		ir_proto_2(ctx, IR_BUILTIN_FUNC, ret_type, arg1_type, arg2_type))
#define BUILTIN_FUNC_3(name, ret_type, arg1_type, arg2_type, arg3_type) \
	ir_const_func(ctx, \
		ir_strl(ctx, name, strlen(name)), \
		ir_proto_3(ctx, IR_BUILTIN_FUNC, ret_type, arg1_type, arg2_type, arg3_type))

static ir_ref llvm2ir_const_expr(ir_ctx *ctx, LLVMValueRef expr);
static ir_ref llvm2ir_auto_cast(ir_ctx *ctx, ir_ref ref, ir_type src_type, ir_type type);
static int llvm2ir_func_ex(ir_ctx *ctx, LLVMValueRef func, LLVMModuleRef module, LLVMValueRef root_func);

static ir_type llvm2ir_type(LLVMTypeRef type)
{
	char *str;
	uint32_t width;

	switch (LLVMGetTypeKind(type)) {
		case LLVMVoidTypeKind:
			return IR_VOID;
		case LLVMIntegerTypeKind:
			width = LLVMGetIntTypeWidth(type);
			if (width == 1) {
				return IR_BOOL;
			} else if (width <= 8) {
				return IR_I8;
			} else if (width <= 16) {
				return IR_I16;
			} else if (width <= 32) {
				return IR_I32;
			} else if (width <= 64) {
				return IR_I64;
			}
			break;
		case LLVMFloatTypeKind:
			return IR_FLOAT;
#if 0
		case LLVMX86_FP80TypeKind:
			// TODO: IR doesn't support "long double". Fallback to "double" ???
			IR_FALLTHROUGH;
#endif
		case LLVMDoubleTypeKind:
			return IR_DOUBLE;
		case LLVMPointerTypeKind:
		case LLVMFunctionTypeKind:
		case LLVMLabelTypeKind:
			return IR_ADDR;
		case LLVMVectorTypeKind:
			IR_ASSERT(0 && "NIY LLVMVectorTypeKind use -fno-vectorize -fno-slp-vectorize");
		default:
			break;
	}

	str = LLVMPrintTypeToString(type);
	fprintf(stderr, "Unsupported LLVM type: %s\n", str);
	IR_ASSERT(0);
	LLVMDisposeMessage(str);
	return IR_BAD_TYPE;
}

static ir_type llvm2ir_unsigned_type(ir_type type)
{
	if (IR_IS_TYPE_SIGNED(type)) {
		IR_ASSERT(type >= IR_I8 && type <= IR_I64);
		type = type - (IR_I8 - IR_U8);
	}
	return type;
}

static ir_type llvm2ir_signed_type(ir_type type)
{
	if (!IR_IS_TYPE_SIGNED(type)) {
		IR_ASSERT(type >= IR_U8 && type <= IR_U64);
		type = type + (IR_I8 - IR_U8);
	}
	return type;
}

static const char *llvm2ir_sym_name(char *buf, const char *name, size_t name_len)
{
	size_t i;
	char c;

	if (name_len > 255) {
		return NULL;
	}
	for (i = 0; i < name_len; i++) {
		c = name[i];
		if (!(c >= 'a' && c <= 'z')
		 && !(c >= 'A' && c <= 'Z')
		 && !(c >= '0' && c <= '9')
		 && c != '_') {
			c = '_';
		}
		buf[i] = c;
	}
	buf[i] = 0;
	return buf;
}

static ir_ref llvm2ir_proto(ir_ctx *ctx, uint32_t cconv, LLVMTypeRef ftype)
{
	uint8_t flags = 0;
	ir_type ret_type;
	uint8_t *arg_types;
	uint32_t i, num_args;
	LLVMTypeRef *types;

	if (cconv == LLVMCCallConv || cconv == LLVMFastCallConv) {
		/* skip */
	} else if (cconv == LLVMX86FastcallCallConv) {
		flags |= IR_FASTCALL_FUNC;
	} else {
		fprintf(stderr, "Unsupported Calling Convention: %d\n", cconv);
		IR_ASSERT(0);
		return 0;
	}
	if (LLVMIsFunctionVarArg(ftype)) {
		flags |= IR_VARARG_FUNC;
	}
	ret_type = llvm2ir_type(LLVMGetReturnType(ftype));
	num_args = LLVMCountParamTypes(ftype);
	types = alloca(sizeof(LLVMTypeRef) * num_args);
	arg_types = alloca(num_args);
	LLVMGetParamTypes(ftype, types);
	for (i = 0; i < num_args; i++) {
		arg_types[i] = llvm2ir_type(types[i]);
	}
	return ir_proto(ctx, flags, ret_type, num_args, arg_types);
}

static bool llvm2ir_is_static(LLVMValueRef op)
{
	switch (LLVMGetLinkage(op)) {
		case LLVMInternalLinkage:
		case LLVMPrivateLinkage:
			return 1;
		default:
			return 0;
	}
}

static ir_ref llvm2ir_op(ir_ctx *ctx, LLVMValueRef op, ir_type type)
{
	ir_ref ref;
	LLVMBool lose;
	const char *name;
	size_t name_len;
	ir_ref proto;
	ir_val val;
	char buf[256];
	LLVMValueKind kind = LLVMGetValueKind(op);

	switch (kind) {
		case LLVMConstantIntValueKind:
			IR_ASSERT(IR_IS_TYPE_INT(type));
			if (IR_IS_TYPE_SIGNED(type)) {
				val.i64 = LLVMConstIntGetSExtValue(op);
			} else {
				val.i64 = LLVMConstIntGetZExtValue(op);
			}
			return ir_const(ctx, val, type);
		case LLVMConstantFPValueKind:
			if (type == IR_DOUBLE) {
				val.d = LLVMConstRealGetDouble(op, &lose);
			} else {
				val.f = (float)LLVMConstRealGetDouble(op, &lose);
				val.u32_hi = 0;
			}
			return ir_const(ctx, val, type);
		case LLVMConstantPointerNullValueKind:
			return IR_NULL;
		case LLVMConstantExprValueKind:
			ref = llvm2ir_const_expr(ctx, op);
			if (ctx->ir_base[ref].type != type) {
				ref = llvm2ir_auto_cast(ctx, ref, ctx->ir_base[ref].type, type);
			}
			return ref;
		case LLVMArgumentValueKind:
		case LLVMInstructionValueKind:
			ref = ir_addrtab_find(ctx->binding, (uintptr_t)op);
			IR_ASSERT(ref != (ir_ref)IR_INVALID_VAL);
			if (ctx->ir_base[ref].op == IR_VAR) {
				return ir_VADDR(ref);
			} else if (ctx->ir_base[ref].type != type) {
				ref = llvm2ir_auto_cast(ctx, ref, ctx->ir_base[ref].type, type);
			}
			return ref;
		case LLVMGlobalVariableValueKind:
			// TODO: resolve variable address
			name = LLVMGetValueName2(op, &name_len);
			if (llvm2ir_is_static(op)) {
				name = llvm2ir_sym_name(buf, name, name_len);
				if (!name) {
					return 0;
				}
			}
			return ir_const_sym(ctx, ir_strl(ctx, name, name_len));
		case LLVMFunctionValueKind:
			// TODO: resolve function address
			proto = llvm2ir_proto(ctx, LLVMGetFunctionCallConv(op), LLVMGlobalGetValueType(op));
			name = LLVMGetValueName2(op, &name_len);
			if (llvm2ir_is_static(op)) {
				name = llvm2ir_sym_name(buf, name, name_len);
				if (!name) {
					return 0;
				}
			}
			return ir_const_func(ctx, ir_strl(ctx, name, name_len), proto);
		case LLVMUndefValueValueKind:
		case LLVMPoisonValueValueKind:
			// TODO: ???
			val.u64 = 0;
			return ir_const(ctx, val, type);
		default:
			fprintf(stderr, "Unsupported LLVM value kind: %d\n", kind);
			IR_ASSERT(0);
			return 0;
	}

	return 0;
}

static ir_ref llvm2ir_retval(ir_ctx *ctx, LLVMValueRef insn)
{
	if (LLVMGetNumOperands(insn) == 0) {
		return IR_UNUSED;
	} else {
		LLVMValueRef op0 = LLVMGetOperand(insn, 0);
		ir_type type = llvm2ir_type(LLVMTypeOf(op0));

		return llvm2ir_op(ctx, op0, type);
	}
}

static void llvm2ir_ret(ir_ctx *ctx, LLVMValueRef insn)
{
	ir_RETURN(llvm2ir_retval(ctx, insn));
}

static ir_ref llvm2ir_jmp(ir_ctx *ctx, LLVMValueRef insn)
{
	ir_ref ref;

	ref = ir_END(); /* END may be converted to LOOP_END later */
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
	return ref;
}

static ir_ref llvm2ir_if(ir_ctx *ctx, LLVMValueRef insn)
{
	ir_ref ref;
	LLVMValueRef op0 = LLVMGetOperand(insn, 0);
	ir_type type = llvm2ir_type(LLVMTypeOf(op0));

	ref = ir_IF(llvm2ir_op(ctx, op0, type));
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
	return ref;
}

static ir_ref llvm2ir_switch(ir_ctx *ctx, LLVMValueRef insn)
{
	ir_ref ref;
	LLVMValueRef op0 = LLVMGetOperand(insn, 0);
	ir_type type = llvm2ir_type(LLVMTypeOf(op0));

	ref = ir_SWITCH(llvm2ir_op(ctx, op0, type));
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
	return ref;
}

static ir_ref llvm2ir_unary_op(ir_ctx *ctx, LLVMValueRef expr, ir_op op)
{
	LLVMValueRef op0 = LLVMGetOperand(expr, 0);
	ir_type type = llvm2ir_type(LLVMTypeOf(expr));
	ir_ref ref;

	ref = ir_fold1(ctx, IR_OPT(op, type), llvm2ir_op(ctx, op0, type));
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return ref;
}

static ir_ref llvm2ir_binary_expr(ir_ctx *ctx, ir_op op, ir_type type, LLVMValueRef expr)
{
	return ir_fold2(ctx, IR_OPT(op, type),
		llvm2ir_op(ctx, LLVMGetOperand(expr, 0), type),
		llvm2ir_op(ctx, LLVMGetOperand(expr, 1), type));
}

static ir_ref llvm2ir_binary_op(ir_ctx *ctx, LLVMOpcode opcode, LLVMValueRef expr, ir_op op)
{
	ir_type type = llvm2ir_type(LLVMTypeOf(expr));
	ir_ref ref;

	if (opcode == LLVMUDiv || opcode == LLVMURem) {
		type = llvm2ir_unsigned_type(type);
	} else if (opcode == LLVMSDiv || opcode == LLVMSRem) {
		type = llvm2ir_signed_type(type);
	}
	ref = llvm2ir_binary_expr(ctx, op, type, expr);
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return ref;
}

static ir_ref llvm2ir_cast_op(ir_ctx *ctx, LLVMValueRef expr, ir_op op, LLVMOpcode opcode)
{
	LLVMValueRef op0 = LLVMGetOperand(expr, 0);
	ir_type src_type, dst_type;
	ir_ref ref;

	src_type = llvm2ir_type(LLVMTypeOf(op0));
	dst_type = llvm2ir_type(LLVMTypeOf(expr));
	if (op == IR_ZEXT) {
		if (src_type == IR_BOOL && (dst_type == IR_I8 || dst_type == IR_U8)) {
			op = IR_BITCAST;
		} else if (ir_type_size[src_type] == ir_type_size[dst_type]) {
			// TODO: may be we need to reset high bits ???
			op = IR_BITCAST;
		}
	} else if (op == IR_SEXT) {
		if (src_type == IR_BOOL) {
			ref = llvm2ir_op(ctx, op0, src_type);
			if (ir_type_size[dst_type] > 1) {
				ref = ir_fold1(ctx, IR_OPT(IR_ZEXT, dst_type), ref);
			} else {
				ref = ir_fold1(ctx, IR_OPT(IR_BITCAST, dst_type), ref);
			}
			ref = ir_fold1(ctx, IR_OPT(IR_NEG, dst_type), ref);
			ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
			return ref;
		}
	} else if (op == IR_TRUNC) {
		if (ir_type_size[src_type] == ir_type_size[dst_type]) {
			// TODO: may be we need to reset high bits ???
			op = IR_BITCAST;
		}
	} else if (op == IR_BITCAST && ir_type_size[src_type] != ir_type_size[dst_type]) {
		op = (ir_type_size[src_type] < ir_type_size[dst_type]) ? IR_ZEXT : IR_TRUNC;
	} else if (op == IR_INT2FP && opcode == LLVMUIToFP) {
		src_type = llvm2ir_unsigned_type(src_type);
	}
	ref = llvm2ir_op(ctx, op0, src_type);
	ref = ir_fold1(ctx, IR_OPT(op, dst_type), ref);
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return ref;
}

static ir_ref llvm2ir_icmp_op(ir_ctx *ctx, LLVMValueRef expr)
{
	LLVMValueRef op0 = LLVMGetOperand(expr, 0);
	LLVMValueRef op1 = LLVMGetOperand(expr, 1);
	ir_type type = llvm2ir_type(LLVMTypeOf(op0));
	ir_ref ref;
	ir_op op;

	switch (LLVMGetICmpPredicate(expr)) {
		case LLVMIntEQ:  op = IR_EQ;  break;
		case LLVMIntNE:  op = IR_NE;  break;
		case LLVMIntUGT: op = IR_UGT; break;
		case LLVMIntUGE: op = IR_UGE; break;
		case LLVMIntULT: op = IR_ULT; break;
		case LLVMIntULE: op = IR_ULE; break;
		case LLVMIntSGT: op = IR_GT;  break;
		case LLVMIntSGE: op = IR_GE;  break;
		case LLVMIntSLT: op = IR_LT;  break;
		case LLVMIntSLE: op = IR_LE;  break;
		default: IR_ASSERT(0); return 0;
	}
	ref = ir_fold2(ctx, IR_OPT(op, IR_BOOL), llvm2ir_op(ctx, op0, type), llvm2ir_op(ctx, op1, type));
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return ref;
}

static ir_ref llvm2ir_fcmp_op_isnan(ir_ctx *ctx, LLVMValueRef expr, ir_type type,
                                    LLVMRealPredicate predicate, LLVMValueRef op0, LLVMValueRef op1)
{
	ir_ref func, ref;

	if (type == IR_DOUBLE) {
		func = BUILTIN_FUNC_1("isnan", IR_BOOL, IR_DOUBLE);
	} else {
		func = BUILTIN_FUNC_1("isnanf", IR_BOOL, IR_FLOAT);
	}
	if (LLVMGetValueKind(op0) == LLVMConstantFPValueKind) {
		ref = ir_CALL_1(IR_BOOL, func, llvm2ir_op(ctx, op1, type));
	} else if (LLVMGetValueKind(op1) == LLVMConstantFPValueKind) {
		ref = ir_CALL_1(IR_BOOL, func, llvm2ir_op(ctx, op0, type));
	} else {
		ref = ir_OR_B(
			ir_CALL_1(IR_BOOL, func, llvm2ir_op(ctx, op0, type)),
			ir_CALL_1(IR_BOOL, func, llvm2ir_op(ctx, op1, type)));
	}
	if (predicate == LLVMRealORD) {
		ref = ir_NOT_B(ref);
	}
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return ref;
}

static ir_ref llvm2ir_fcmp_op(ir_ctx *ctx, LLVMValueRef expr)
{
	LLVMValueRef op0 = LLVMGetOperand(expr, 0);
	LLVMValueRef op1 = LLVMGetOperand(expr, 1);
	ir_type type = llvm2ir_type(LLVMTypeOf(op0));
	ir_ref ref;
	ir_op op;
	LLVMRealPredicate predicate = LLVMGetFCmpPredicate(expr);

	switch (predicate) {
		case LLVMRealOEQ:
		case LLVMRealUEQ: op = IR_EQ;  break;
		case LLVMRealONE:
		case LLVMRealUNE: op = IR_NE;  break;
		case LLVMRealUGT: op = IR_UGT; break;
		case LLVMRealUGE: op = IR_UGE; break;
		case LLVMRealULT: op = IR_ULT; break;
		case LLVMRealULE: op = IR_ULE; break;
		case LLVMRealOGT: op = IR_GT;  break;
		case LLVMRealOGE: op = IR_GE;  break;
		case LLVMRealOLT: op = IR_LT;  break;
		case LLVMRealOLE: op = IR_LE;  break;
		case LLVMRealUNO:
		case LLVMRealORD:
			return llvm2ir_fcmp_op_isnan(ctx, expr, type, predicate, op0, op1);
		default: IR_ASSERT(0); return 0;
	}
	ref = ir_fold2(ctx, IR_OPT(op, IR_BOOL), llvm2ir_op(ctx, op0, type), llvm2ir_op(ctx, op1, type));
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return ref;
}

static ir_ref llvm2ir_cond_op(ir_ctx *ctx, LLVMValueRef expr)
{
	LLVMValueRef op0 = LLVMGetOperand(expr, 0);
	LLVMValueRef op1 = LLVMGetOperand(expr, 1);
	LLVMValueRef op2 = LLVMGetOperand(expr, 2);
	ir_type type = llvm2ir_type(LLVMTypeOf(expr));
	ir_ref ref;

	ref = ir_fold3(ctx, IR_OPT(IR_COND, type), llvm2ir_op(ctx, op0, IR_BOOL), llvm2ir_op(ctx, op1, type), llvm2ir_op(ctx, op2, type));
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return ref;
}

static void llvm2ir_alloca(ir_ctx *ctx, LLVMValueRef insn)
{
	LLVMValueRef op0 = LLVMGetOperand(insn, 0);
	ir_ref ref;

	if (LLVMGetValueKind(op0) == LLVMConstantIntValueKind && LLVMConstIntGetZExtValue(op0) == 1) {
		LLVMTypeKind type_kind = LLVMGetTypeKind(LLVMGetAllocatedType(insn));

		if (type_kind == LLVMIntegerTypeKind
		 || type_kind == LLVMFloatTypeKind
		 || type_kind == LLVMDoubleTypeKind
		 || type_kind == LLVMPointerTypeKind
		 || type_kind == LLVMFunctionTypeKind
		 || type_kind == LLVMLabelTypeKind) {
			ir_type type = llvm2ir_type(LLVMGetAllocatedType(insn));

			size_t name_len;
			const char *name = LLVMGetValueName2(insn, &name_len);
			char buf[32];

			if (!name || !name_len) {
				snprintf(buf, sizeof(buf), "var_%d", ctx->insns_count);
				name = buf;
			}
			ref = ir_VAR(type, name);
		} else {
			ref = ir_ALLOCA(ir_MUL_I32(llvm2ir_op(ctx, op0, IR_I32),
				ir_const_i32(ctx, LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, LLVMGetAllocatedType(insn)))));
		}
	} else {
		ref = ir_ALLOCA(ir_MUL_I32(llvm2ir_op(ctx, op0, IR_I32),
			ir_const_i32(ctx, LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, LLVMGetAllocatedType(insn)))));
	}
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
}

static void llvm2ir_load(ir_ctx *ctx, LLVMValueRef insn)
{
	LLVMValueRef op0 = LLVMGetOperand(insn, 0);
	ir_type type = llvm2ir_type(LLVMTypeOf(insn));
	ir_ref ref;

	if (LLVMGetValueKind(op0) == LLVMInstructionValueKind) {
		ref = ir_addrtab_find(ctx->binding, (uintptr_t)op0);
		if (ctx->ir_base[ref].op == IR_VAR) {
			ref = ir_VLOAD(type, ref);
		} else {
			if (ctx->ir_base[ref].type != IR_ADDR) {
				ref = llvm2ir_auto_cast(ctx, ref, ctx->ir_base[ref].type, IR_ADDR);
			}
			ref = ir_LOAD(type, ref);
		}
	} else {
		ref = llvm2ir_op(ctx, op0, IR_ADDR);
		ref = ir_LOAD(type, ref);
	}
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
}

static void llvm2ir_store(ir_ctx *ctx, LLVMValueRef insn)
{
	LLVMValueRef op0 = LLVMGetOperand(insn, 0);
	LLVMValueRef op1 = LLVMGetOperand(insn, 1);
	ir_type type = llvm2ir_type(LLVMTypeOf(op0));
	ir_ref ref, val;

	val = llvm2ir_op(ctx, op0, type);
	if (LLVMGetValueKind(op1) == LLVMInstructionValueKind) {
		ref = ir_addrtab_find(ctx->binding, (uintptr_t)op1);
		if (ctx->ir_base[ref].op == IR_VAR) {
			ir_VSTORE(ref, val);
		} else {
			if (ctx->ir_base[ref].type != IR_ADDR) {
				ref = llvm2ir_auto_cast(ctx, ref, ctx->ir_base[ref].type, IR_ADDR);
			}
			ir_STORE(ref, val);
		}
	} else {
		ref = llvm2ir_op(ctx, op1, IR_ADDR);
		ir_STORE(ref, val);
	}
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ctx->control);
}

static ir_type llvm2ir_overflow_type(LLVMTypeRef stype)
{
	ir_type type;

	IR_ASSERT(LLVMGetTypeKind(stype) == LLVMStructTypeKind);
	IR_ASSERT(LLVMCountStructElementTypes(stype) == 2);
	IR_ASSERT(llvm2ir_type(LLVMStructGetTypeAtIndex(stype, 1)) == IR_BOOL);
	stype = LLVMStructGetTypeAtIndex(stype, 0);
	type = llvm2ir_type(stype);
	IR_ASSERT(IR_IS_TYPE_INT(type));
	return type;
}

static void llvm2ir_va_arg(ir_ctx *ctx, LLVMValueRef insn)
{
	ir_type type = llvm2ir_type(LLVMTypeOf(insn));
	ir_ref ref = ir_VA_ARG(type, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
}

#define STR_START(name, name_len, str) (name_len >= strlen(str) && memcmp(name, str, strlen(str)) == 0)
#define STR_EQUAL(name, name_len, str) (name_len == strlen(str) && memcmp(name, str, strlen(str)) == 0)

static ir_ref llvm2ir_intrinsic(ir_ctx *ctx, LLVMValueRef insn, LLVMTypeRef ftype, uint32_t count, const char *name, size_t name_len)
{
	ir_type type;
	ir_ref func;

	if (STR_START(name, name_len, "llvm.lifetime.")) {
		/* skip */
		return IR_NULL;
	} else if (STR_START(name, name_len, "llvm.dbg.")) {
		/* skip */
		return IR_NULL;
	} else if (STR_EQUAL(name, name_len, "llvm.experimental.noalias.scope.decl")) {
		/* skip */
		return IR_NULL;
	} else if (STR_EQUAL(name, name_len, "llvm.assume")) {
		/* skip */
		return IR_NULL;
	} else if (STR_START(name, name_len, "llvm.smax.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_signed_type(type);
		return llvm2ir_binary_expr(ctx, IR_MAX, type, insn);
	} else if (STR_START(name, name_len, "llvm.umax.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_unsigned_type(type);
		return llvm2ir_binary_expr(ctx, IR_MAX, type, insn);
	} else if (STR_START(name, name_len, "llvm.maxnum.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		return llvm2ir_binary_expr(ctx, IR_MAX, type, insn);
	} else if (STR_START(name, name_len, "llvm.smin.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_signed_type(type);
		return llvm2ir_binary_expr(ctx, IR_MIN, type, insn);
	} else if (STR_START(name, name_len, "llvm.umin.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_unsigned_type(type);
		return llvm2ir_binary_expr(ctx, IR_MIN, type, insn);
	} else if (STR_START(name, name_len, "llvm.minnum.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		return llvm2ir_binary_expr(ctx, IR_MIN, type, insn);
	} else if (STR_START(name, name_len, "llvm.sadd.with.overflow.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_overflow_type(LLVMGetReturnType(ftype));
		type = llvm2ir_signed_type(type);
		return llvm2ir_binary_expr(ctx, IR_ADD_OV, type, insn);
	} else if (STR_START(name, name_len, "llvm.uadd.with.overflow.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_overflow_type(LLVMGetReturnType(ftype));
		type = llvm2ir_unsigned_type(type);
		return llvm2ir_binary_expr(ctx, IR_ADD_OV, type, insn);
	} else if (STR_START(name, name_len, "llvm.ssub.with.overflow.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_overflow_type(LLVMGetReturnType(ftype));
		type = llvm2ir_signed_type(type);
		return llvm2ir_binary_expr(ctx, IR_SUB_OV, type, insn);
	} else if (STR_START(name, name_len, "llvm.usub.with.overflow.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_overflow_type(LLVMGetReturnType(ftype));
		type = llvm2ir_unsigned_type(type);
		return llvm2ir_binary_expr(ctx, IR_SUB_OV, type, insn);
	} else if (STR_START(name, name_len, "llvm.smul.with.overflow.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_overflow_type(LLVMGetReturnType(ftype));
		type = llvm2ir_signed_type(type);
		return llvm2ir_binary_expr(ctx, IR_MUL_OV, type, insn);
	} else if (STR_START(name, name_len, "llvm.umul.with.overflow.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_overflow_type(LLVMGetReturnType(ftype));
		type = llvm2ir_unsigned_type(type);
		return llvm2ir_binary_expr(ctx, IR_MUL_OV, type, insn);
	} else if (STR_START(name, name_len, "llvm.sadd.sat.")) {
		ir_ref ref, overflow, op0, op1, limit;
		ir_val val;

		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_signed_type(type);
		op0 = llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type);
		op1 = llvm2ir_op(ctx, LLVMGetOperand(insn, 1), type);
		if (IR_IS_CONST_REF(op0)) {
			IR_ASSERT(ctx->ir_base[op0].type == type);
			if (ctx->ir_base[op0].val.i64 >= 0) {
				// positive_x + MIN -> y, positive_x + MAX = MAX
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x7f; break;
					case 2: val.u64 = 0x7fff; break;
					case 4: val.u64 = 0x7fffffff; break;
					case 8: val.u64 = 0x7fffffffffffffff; break;
					default: IR_ASSERT(0);
				}
			} else {
				// negative_x + MIN -> MIN, negative_x + MAX = y
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x80; break;
					case 2: val.u64 = 0x8000; break;
					case 4: val.u64 = 0x80000000; break;
					case 8: val.u64 = 0x8000000000000000; break;
					default: IR_ASSERT(0);
				}
			}
			limit = ir_const(ctx, val, type);
		} else if (IR_IS_CONST_REF(op1)) {
			IR_ASSERT(ctx->ir_base[op1].type == type);
			if (ctx->ir_base[op1].val.i64 >= 0) {
				// MIN + positive_x -> y, MAX + positive_x = MAX
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x7f; break;
					case 2: val.u64 = 0x7fff; break;
					case 4: val.u64 = 0x7fffffff; break;
					case 8: val.u64 = 0x7fffffffffffffff; break;
					default: IR_ASSERT(0);
				}
			} else {
				// MIN + negative_x -> MIN, MAX + negative_x = y
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x80; break;
					case 2: val.u64 = 0x8000; break;
					case 4: val.u64 = 0x80000000; break;
					case 8: val.u64 = 0x8000000000000000; break;
					default: IR_ASSERT(0);
				}
			}
			limit = ir_const(ctx, val, type);
		} else {
			ref = ir_SHR(type, op0, ir_const_u8(ctx, ir_type_size[type] * 8 - 1));
			switch (ir_type_size[type]) {
				case 1: val.u64 = 0x7f; break;
				case 2: val.u64 = 0x7fff; break;
				case 4: val.u64 = 0x7fffffff; break;
				case 8: val.u64 = 0x7fffffffffffffff; break;
				default: IR_ASSERT(0);
			}
			limit = ir_ADD(type, ref, ir_const(ctx, val, type));
		}
		ref = ir_fold2(ctx, IR_OPT(IR_ADD_OV, type), op0, op1);
		overflow = ir_OVERFLOW(ref);
		return ir_COND(type, overflow, limit, ref);
	} else if (STR_START(name, name_len, "llvm.uadd.sat.")) {
		ir_ref ref, overflow;
		ir_val val;

		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_unsigned_type(type);
		ref = llvm2ir_binary_expr(ctx, IR_ADD_OV, type, insn);
		overflow = ir_OVERFLOW(ref);
		switch (ir_type_size[type]) {
			case 1: val.u64 = 0xff; break;
			case 2: val.u64 = 0xffff; break;
			case 4: val.u64 = 0xffffffff; break;
			case 8: val.u64 = 0xffffffffffffffff; break;
			default: IR_ASSERT(0);
		}
		return ir_COND(type, overflow, ir_const(ctx, val, type), ref);
	} else if (STR_START(name, name_len, "llvm.ssub.sat.")) {
		ir_ref ref, overflow, op0, op1, limit;
		ir_val val;

		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_signed_type(type);
		op0 = llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type);
		op1 = llvm2ir_op(ctx, LLVMGetOperand(insn, 1), type);
		if (IR_IS_CONST_REF(op0)) {
			IR_ASSERT(ctx->ir_base[op0].type == type);
			if (ctx->ir_base[op0].val.i64 >= 0) {
				// positive_x - MIN -> MAX, positive_x - MAX = y
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x7f; break;
					case 2: val.u64 = 0x7fff; break;
					case 4: val.u64 = 0x7fffffff; break;
					case 8: val.u64 = 0x7fffffffffffffff; break;
					default: IR_ASSERT(0);
				}
			} else {
				// negative_x - MIN -> y, negative_x - MAX = MIN
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x80; break;
					case 2: val.u64 = 0x8000; break;
					case 4: val.u64 = 0x80000000; break;
					case 8: val.u64 = 0x8000000000000000; break;
					default: IR_ASSERT(0);
				}
			}
			limit = ir_const(ctx, val, type);
		} else if (IR_IS_CONST_REF(op1)) {
			IR_ASSERT(ctx->ir_base[op1].type == type);
			if (ctx->ir_base[op1].val.i64 >= 0) {
				// MIN - positive_x -> MIN, MAX - positive_x = y
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x80; break;
					case 2: val.u64 = 0x8000; break;
					case 4: val.u64 = 0x80000000; break;
					case 8: val.u64 = 0x8000000000000000; break;
					default: IR_ASSERT(0);
				}
			} else {
				// MIN - negative_x -> y, MAX - negative_x = MAX
				switch (ir_type_size[type]) {
					case 1: val.u64 = 0x7f; break;
					case 2: val.u64 = 0x7fff; break;
					case 4: val.u64 = 0x7fffffff; break;
					case 8: val.u64 = 0x7fffffffffffffff; break;
					default: IR_ASSERT(0);
				}
			}
			limit = ir_const(ctx, val, type);
		} else {
			ref = ir_SHR(type, op0, ir_const_u8(ctx, ir_type_size[type] * 8 - 1));
			switch (ir_type_size[type]) {
				case 1: val.u64 = 0x7f; break;
				case 2: val.u64 = 0x7fff; break;
				case 4: val.u64 = 0x7fffffff; break;
				case 8: val.u64 = 0x7fffffffffffffff; break;
				default: IR_ASSERT(0);
			}
			limit = ir_ADD(type, ref, ir_const(ctx, val, type));
		}
		ref = ir_fold2(ctx, IR_OPT(IR_SUB_OV, type), op0, op1);
		overflow = ir_OVERFLOW(ref);
		return ir_COND(type, overflow, limit, ref);
	} else if (STR_START(name, name_len, "llvm.usub.sat.")) {
		ir_ref ref, overflow;
		ir_val val;

		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		type = llvm2ir_unsigned_type(type);
		ref = llvm2ir_binary_expr(ctx, IR_SUB_OV, type, insn);
		overflow = ir_OVERFLOW(ref);
		val.u64 = 0;
		return ir_COND(type, overflow, ir_const(ctx, val, type), ref);
	} else if (STR_START(name, name_len, "llvm.abs.")) {
		IR_ASSERT(count == 2);
		// TODO: support for the second argument
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		return ir_ABS(type, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.fabs.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		return ir_ABS(type, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.bswap.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		return ir_BSWAP(type, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.fshl.")
			&& count == 3
			&& LLVMGetOperand(insn, 0) == LLVMGetOperand(insn, 1)) {
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		return ir_ROL(type,
			llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 2), type));
	} else if (STR_START(name, name_len, "llvm.fshr.")
			&& count == 3
			&& LLVMGetOperand(insn, 0) == LLVMGetOperand(insn, 1)) {
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_INT(type));
		return ir_ROR(type,
			llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 2), type));
	} else if (STR_EQUAL(name, name_len, "llvm.va_start")) {
		IR_ASSERT(count == 1);
		ir_VA_START(llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_ADDR));
		return IR_NULL;
	} else if (STR_EQUAL(name, name_len, "llvm.va_end")) {
		IR_ASSERT(count == 1);
		ir_VA_END(llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_ADDR));
		return IR_NULL;
	} else if (STR_EQUAL(name, name_len, "llvm.va_copy")) {
		IR_ASSERT(count == 2);
		ir_VA_COPY(
			llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_ADDR),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 1), IR_ADDR));
		return IR_NULL;
	} else if (STR_START(name, name_len, "llvm.ctpop.")) {
		LLVMValueRef op0 = LLVMGetOperand(insn, 0);
		ir_type type = llvm2ir_type(LLVMTypeOf(op0));

		return ir_CTPOP(type, llvm2ir_op(ctx, op0, type));
	} else if (STR_START(name, name_len, "llvm.ctlz.")) {
		LLVMValueRef op0 = LLVMGetOperand(insn, 0);
		ir_type type = llvm2ir_type(LLVMTypeOf(op0));

		// TODO: support for the second argument
		return ir_CTLZ(type, llvm2ir_op(ctx, op0, type));
	} else if (STR_START(name, name_len, "llvm.cttz.")) {
		LLVMValueRef op0 = LLVMGetOperand(insn, 0);
		ir_type type = llvm2ir_type(LLVMTypeOf(op0));

		// TODO: support for the second argument
		return ir_CTTZ(type, llvm2ir_op(ctx, op0, type));
	} else if (STR_START(name, name_len, "llvm.memset.")) {
		IR_ASSERT(count == 3 || count == 4);
		func = BUILTIN_FUNC_3("memset", IR_ADDR, IR_ADDR, IR_I32, IR_SIZE_T);
		return ir_CALL_3(IR_VOID, func,
			llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_ADDR),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 1), IR_I8),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 2), IR_SIZE_T));
	} else if (STR_START(name, name_len, "llvm.memcpy.")) {
		IR_ASSERT(count == 3 || count == 4);
		func = BUILTIN_FUNC_3("memcpy", IR_ADDR, IR_ADDR, IR_ADDR, IR_SIZE_T);
		return ir_CALL_3(IR_VOID, func,
			llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_ADDR),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 1), IR_ADDR),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 2), IR_SIZE_T));
	} else if (STR_START(name, name_len, "llvm.memmove.")) {
		IR_ASSERT(count == 3 || count == 4);
		func = BUILTIN_FUNC_3("memmove", IR_ADDR, IR_ADDR, IR_ADDR, IR_SIZE_T);
		return ir_CALL_3(IR_VOID, func,
			llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_ADDR),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 1), IR_ADDR),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 2), IR_SIZE_T));
	} else if (STR_START(name, name_len, "llvm.frameaddress.")) {
		IR_ASSERT(LLVMGetValueKind(LLVMGetOperand(insn, 0)) == LLVMConstantIntValueKind);
		IR_ASSERT(LLVMConstIntGetSExtValue(LLVMGetOperand(insn, 0)) == 0);
		return ir_FRAME_ADDR();
	} else if (STR_EQUAL(name, name_len, "llvm.stacksave")) {
		IR_ASSERT(count == 0);
		return ir_BLOCK_BEGIN();
	} else if (STR_EQUAL(name, name_len, "llvm.stackrestore")) {
		IR_ASSERT(count == 1);
		ir_BLOCK_END(llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_ADDR));
		return ctx->control;
	} else if (STR_EQUAL(name, name_len, "llvm.debugtrap")) {
		ir_TRAP();
		return ctx->control;
	} else if (STR_START(name, name_len, "llvm.sqrt.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("sqrt", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("sqrtf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.sin.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("sin", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("sinf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.cos.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("cos", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("cosf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.pow.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("pow", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("powf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_2(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 1), type));
	} else if (STR_START(name, name_len, "llvm.exp.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("exp", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("expf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.exp2.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("exp2", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("exp2f", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.exp10.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("exp10", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("exp10f", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.ldexp.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_2("ldexp", IR_DOUBLE, IR_DOUBLE, IR_I32);
		} else {
			func = BUILTIN_FUNC_2("ldexpf", IR_FLOAT, IR_FLOAT, IR_I32);
		}
		return ir_CALL_2(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 1), IR_I32));
	} else if (STR_START(name, name_len, "llvm.log.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("log", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("logf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.log2.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("log2", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("log2f", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.log10.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("log10", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("log10f", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.copysign.")) {
		IR_ASSERT(count == 2);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_2("copysign", IR_DOUBLE, IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_2("copysignf", IR_FLOAT, IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_2(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type),
			llvm2ir_op(ctx, LLVMGetOperand(insn, 1), type));
	} else if (STR_START(name, name_len, "llvm.floor.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("floor", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("floorf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.ceil.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("ceil", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("ceilf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.trunc.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("trunc", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("truncf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.round.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("round", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("roundf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.rint.")) {
		IR_ASSERT(count == 1);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		if (type == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("rint", IR_DOUBLE, IR_DOUBLE);
		} else {
			func = BUILTIN_FUNC_1("rintf", IR_FLOAT, IR_FLOAT);
		}
		return ir_CALL_1(type, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type));
	} else if (STR_START(name, name_len, "llvm.fmuladd.")
			|| STR_START(name, name_len, "llvm.fma.")) {
		ir_ref op1, op2;

		IR_ASSERT(count == 3);
		type = llvm2ir_type(LLVMGetReturnType(ftype));
		IR_ASSERT(IR_IS_TYPE_FP(type));
		op1 = llvm2ir_op(ctx, LLVMGetOperand(insn, 0), type);
		op2 = llvm2ir_op(ctx, LLVMGetOperand(insn, 1), type);
		if (ctx->ir_base[op1].op == IR_NEG) {
			op1 = ctx->ir_base[op1].op1;
			return ir_fold2(ctx, IR_OPT(IR_SUB, type),
				llvm2ir_op(ctx, LLVMGetOperand(insn, 2), type),
				ir_fold2(ctx, IR_OPT(IR_MUL, type), op1, op2));
		} else if (ctx->ir_base[op2].op == IR_NEG) {
			op2 = ctx->ir_base[op2].op1;
			return ir_fold2(ctx, IR_OPT(IR_SUB, type),
				llvm2ir_op(ctx, LLVMGetOperand(insn, 2), type),
				ir_fold2(ctx, IR_OPT(IR_MUL, type), op1, op2));
		} else {
			return ir_fold2(ctx, IR_OPT(IR_ADD, type),
				ir_fold2(ctx, IR_OPT(IR_MUL, type), op1, op2),
				llvm2ir_op(ctx, LLVMGetOperand(insn, 2), type));
		}
	} else if (STR_EQUAL(name, name_len, "llvm.bitreverse.i1")) {
		IR_ASSERT(count == 1);
		return llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_BOOL);
	} else if (STR_START(name, name_len, "llvm.is.constant.")) {
		// TODO:
		return IR_FALSE;
	} else {
		fprintf(stderr, "Unsupported LLVM intrinsic: %s\n", name);
		IR_ASSERT(0);
	}
	return IR_UNUSED;
}

static ir_ref llvm2ir_builtin(ir_ctx *ctx, LLVMValueRef insn, LLVMTypeRef ftype, uint32_t count, const char *name, size_t name_len)
{
	ir_ref func;

	if (STR_EQUAL(name, name_len, "abs")) {
		if (count == 1 && llvm2ir_type(LLVMGetReturnType(ftype)) == IR_I32) {
			return ir_ABS(IR_I32, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_I32));
		}
	} else if (STR_EQUAL(name, name_len, "labs")) {
		if (count == 1 && llvm2ir_type(LLVMGetReturnType(ftype)) == IR_I64) {
			return ir_ABS(IR_I64, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_I64));
		}
	} else if (STR_EQUAL(name, name_len, "sqrt")) {
		if (count == 1 && llvm2ir_type(LLVMGetReturnType(ftype)) == IR_DOUBLE) {
			func = BUILTIN_FUNC_1("sqrt", IR_DOUBLE, IR_DOUBLE);
			return ir_CALL_1(IR_DOUBLE, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_DOUBLE));
		}
	} else if (STR_EQUAL(name, name_len, "sqrtf")) {
		if (count == 1 && llvm2ir_type(LLVMGetReturnType(ftype)) == IR_FLOAT) {
			func = BUILTIN_FUNC_1("sqrtf", IR_FLOAT, IR_FLOAT);
			return ir_CALL_1(IR_FLOAT, func, llvm2ir_op(ctx, LLVMGetOperand(insn, 0), IR_FLOAT));
		}
	}
	return IR_UNUSED;
}

static int llvm2ir_inline_cost(LLVMValueRef func)
{
	int count = 0;
	LLVMBasicBlockRef bb = LLVMGetFirstBasicBlock(func);
	LLVMValueRef insn;

	for (bb = LLVMGetFirstBasicBlock(func); bb; bb = LLVMGetNextBasicBlock(bb)) {
		for (insn = LLVMGetFirstInstruction(bb); insn; insn = LLVMGetNextInstruction(insn)) {
			count++;
		}
	}
	return count;
}

static bool llvm2ir_inline(ir_ctx *ctx, LLVMValueRef insn, LLVMValueRef func, LLVMModuleRef module, LLVMValueRef root_func)
{
	uint32_t i, count = LLVMGetNumArgOperands(insn);
	ir_ref ref;

	ref = ir_addrtab_find(ctx->binding, (uintptr_t)func);
	if (ref == 1) {
		return 0;
	}
	ir_addrtab_set(ctx->binding, (uintptr_t)func, 1);

	IR_ASSERT(count == LLVMCountParams(func));
	for (i = 0; i < count; i++) {
		LLVMValueRef arg = LLVMGetOperand(insn, i);
		ir_type type = llvm2ir_type(LLVMTypeOf(arg));
		ref = llvm2ir_op(ctx, arg, type);
		ir_addrtab_set(ctx->binding, (uintptr_t)LLVMGetParam(func, i), ref);
	}
	ref = llvm2ir_func_ex(ctx, func, module, root_func);
	if (!ref) {
		return 0;
	} else if (ref != 1) {
		ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
	} else if (!ctx->control) {
		ir_val val;
		ir_type type = llvm2ir_type(LLVMGetReturnType(LLVMGlobalGetValueType(func)));

		ir_BEGIN(IR_UNUSED);
		if (type != IR_VOID) {
			val.u64 = 0;
			ref = ir_const(ctx, val, type);
			ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
		}
	}

	ir_addrtab_set(ctx->binding, (uintptr_t)func, 0);

	return 1;
}

static void llvm2ir_call(ir_ctx *ctx, LLVMValueRef insn, LLVMModuleRef module, LLVMValueRef root_func)
{
	LLVMValueRef arg, func = LLVMGetCalledValue(insn);
	LLVMTypeRef ftype = LLVMGetCalledFunctionType(insn);
//	uint32_t cconv = LLVMGetInstructionCallConv(insn);
//	LLVMBool tail = LLVMIsTailCall(insn);
	ir_type type;
	uint32_t i, count = LLVMGetNumArgOperands(insn);
	ir_ref ref;
	ir_ref *args;

	if (LLVMGetValueKind(func) == LLVMFunctionValueKind) {
		size_t name_len;
		const char *name;

		name = LLVMGetValueName2(func, &name_len);
		if (STR_START(name, name_len, "llvm.")) {
			ref = llvm2ir_intrinsic(ctx, insn, ftype, count, name, name_len);
			if (ref) {
				if (ref != IR_NULL) {
					ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
				}
				return;
			}
		} else {
			ref = llvm2ir_builtin(ctx, insn, ftype, count, name, name_len);
			if (ref) {
				if (ref != IR_NULL) {
					ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
				}
				return;
			}
		}

		if (ctx->flags & IR_OPT_INLINE) {
			LLVMValueRef fn = LLVMGetNamedFunction(module, name);
			if (fn && fn != root_func && !LLVMIsDeclaration(fn)) {
				LLVMTypeRef ftype = LLVMGlobalGetValueType(fn);
				if (!LLVMIsFunctionVarArg(ftype) && count == LLVMCountParams(fn)) {
					if (!LLVMGetEnumAttributeAtIndex(fn, LLVMAttributeFunctionIndex, LLVMAttrNoInline)) {
						bool do_inline = 0;
						if (LLVMGetEnumAttributeAtIndex(fn, LLVMAttributeFunctionIndex, LLVMAttrAlwaysInline)) {
							do_inline = 1;
						} else if (LLVMGetEnumAttributeAtIndex(fn, LLVMAttributeFunctionIndex, LLVMAttrInlineHint)) {
							if (LLVMCountBasicBlocks(fn) <= LLVM2IR_INLINE_MAX_HINT_BLOCKS
							 && llvm2ir_inline_cost(fn) <= LLVM2IR_INLINE_MAX_HINT_COST) {
								do_inline = 1;
							}
						} else {
							if (LLVMCountBasicBlocks(fn) <= LLVM2IR_INLINE_MAX_BLOCKS
							 && llvm2ir_inline_cost(fn) <= LLVM2IR_INLINE_MAX_COST) {
								do_inline = 1;
							}
						}
						if (do_inline && llvm2ir_inline(ctx, insn, fn, module, root_func)) {
							return;
						}
					}
				}
			}
		}
	}

	args = alloca(sizeof(ir_ref) * count);
	for (i = 0; i < count; i++) {
		arg = LLVMGetOperand(insn, i);
		type = llvm2ir_type(LLVMTypeOf(arg));
		args[i] = llvm2ir_op(ctx, arg, type);
	}
	do {
		if (LLVMIsTailCall(insn)) {
			LLVMValueRef next_insn = LLVMGetNextInstruction(insn);

			if (LLVMGetInstructionOpcode(next_insn) == LLVMRet
			 && LLVMGetNumOperands(next_insn) == 1
			 && LLVMGetOperand(next_insn, 1) == insn) {
				ref = ir_TAILCALL_N(llvm2ir_type(LLVMGetReturnType(ftype)), llvm2ir_op(ctx, func, IR_ADDR), count, args);
				break;
			}
		}
		ref = ir_CALL_N(llvm2ir_type(LLVMGetReturnType(ftype)), llvm2ir_op(ctx, func, IR_ADDR), count, args);
	} while (0);
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
}

static bool llvm2ir_extract(ir_ctx *ctx, LLVMValueRef expr)
{
	LLVMValueRef op0;
	ir_ref ref;
	uint32_t n;

	IR_ASSERT(LLVMGetNumOperands(expr) == 1 && LLVMGetNumIndices(expr) == 1);
	op0 = LLVMGetOperand(expr, 0);
	ref = ir_addrtab_find(ctx->binding, (uintptr_t)op0);
	IR_ASSERT(ref != (ir_ref)IR_INVALID_VAL);
	if (ctx->ir_base[ref].op != IR_ADD_OV
	 && ctx->ir_base[ref].op != IR_SUB_OV
	 && ctx->ir_base[ref].op != IR_MUL_OV
	 && ctx->ir_base[ref].op != IR_PHI) {
		return 0;
	}
	n = *LLVMGetIndices(expr);
	if (n == 0) {
		/* use the same result */
	} else if (n == 1) {
		ref = ir_OVERFLOW(ref);
	} else {
		return 0;
	}
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
	return 1;
}

static void llvm2ir_freeze(ir_ctx *ctx, LLVMValueRef expr)
{
	LLVMValueRef op0;
	ir_ref ref;

	IR_ASSERT(LLVMGetNumOperands(expr) == 1);
	op0 = LLVMGetOperand(expr, 0);
	ref = ir_addrtab_find(ctx->binding, (uintptr_t)op0);
	IR_ASSERT(ref != (ir_ref)IR_INVALID_VAL);
	ir_addrtab_set(ctx->binding, (uintptr_t)expr, ref);
}

static uintptr_t llvm2ir_const_element_ptr_offset(LLVMTargetDataRef target_data, LLVMValueRef expr)
{
	LLVMValueRef op;
	LLVMTypeRef type;
	LLVMTypeKind type_kind;
	uint32_t i, count;
	uintptr_t index, offset = 0;

	type = LLVMGetGEPSourceElementType(expr);
	type_kind = LLVMGetTypeKind(type);

	op = LLVMGetOperand(expr, 1);
	IR_ASSERT(LLVMGetValueKind(op) == LLVMConstantIntValueKind);
	index = LLVMConstIntGetSExtValue(op);
	offset += index * LLVMABISizeOfType(target_data, type);

	count = LLVMGetNumOperands(expr);
	for (i = 2; i < count; i++) {
		op = LLVMGetOperand(expr, i);
		switch (type_kind) {
			case LLVMStructTypeKind:
				IR_ASSERT(LLVMGetValueKind(op) == LLVMConstantIntValueKind);
				index = LLVMConstIntGetSExtValue(op);
				offset += LLVMOffsetOfElement(target_data, type, index);
				type = LLVMStructGetTypeAtIndex(type, index);
				break;
			case LLVMPointerTypeKind:
				IR_ASSERT(!LLVMPointerTypeIsOpaque(type));
				IR_FALLTHROUGH;
			case LLVMArrayTypeKind:
				IR_ASSERT(LLVMGetValueKind(op) == LLVMConstantIntValueKind);
				index = LLVMConstIntGetSExtValue(op);
				type = LLVMGetElementType(type);
				offset += index * LLVMABISizeOfType(target_data, type);
				break;
			default:
				IR_ASSERT(0);
				return 0;
		}
		type_kind = LLVMGetTypeKind(type);
    }
	return offset;
}

static ir_ref llvm2ir_const_element_ptr(ir_ctx *ctx, LLVMValueRef expr)
{
	LLVMValueRef op0 = LLVMGetOperand(expr, 0);
	uintptr_t offset = llvm2ir_const_element_ptr_offset((LLVMTargetDataRef)ctx->rules, expr);
	ir_ref ref = llvm2ir_op(ctx, op0, IR_ADDR);

    if (offset) {
		ref = ir_ADD_A(ref, ir_const_addr(ctx, (uintptr_t)offset));
    }
	return ref;
}

static void llvm2ir_element_ptr(ir_ctx *ctx, LLVMValueRef insn)
{
	LLVMValueRef op;
	LLVMValueRef op0 = LLVMGetOperand(insn, 0);
	LLVMTypeRef type = LLVMTypeOf(op0);
	LLVMTypeKind type_kind;
	uint32_t i, count;
	uintptr_t index, offset = 0, size;
	ir_ref ref = llvm2ir_op(ctx, op0, IR_ADDR);

	type_kind = LLVMGetTypeKind(type);
	IR_ASSERT(type_kind == LLVMPointerTypeKind);
	type = LLVMGetGEPSourceElementType(insn);
	type_kind = LLVMGetTypeKind(type);

	op = LLVMGetOperand(insn, 1);
	if (LLVMGetValueKind(op) == LLVMConstantIntValueKind) {
		index = LLVMConstIntGetSExtValue(op);
		offset += index * LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type);
	} else {
		ir_ref idx = llvm2ir_op(ctx, op, IR_ADDR);

		size = LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type);
		if (size == 1) {
			ref = ir_ADD_A(ref, idx);
		} else {
			if (ctx->ir_base[idx].op == IR_NEG) {
				idx = ctx->ir_base[idx].op1;
				ref = ir_SUB_A(ref, ir_MUL_A(
					idx,
					ir_const_addr(ctx, LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type))));
			} else {
				ref = ir_ADD_A(ref, ir_MUL_A(
					idx,
					ir_const_addr(ctx, LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type))));
			}
		}
	}

	count = LLVMGetNumOperands(insn);
	for (i = 2; i < count; i++) {
		op = LLVMGetOperand(insn, i);
		switch (type_kind) {
			case LLVMStructTypeKind:
				IR_ASSERT(LLVMGetValueKind(op) == LLVMConstantIntValueKind);
				index = LLVMConstIntGetSExtValue(op);
				offset += LLVMOffsetOfElement((LLVMTargetDataRef)ctx->rules, type, index);
				type = LLVMStructGetTypeAtIndex(type, index);
				break;
			case LLVMPointerTypeKind:
				IR_ASSERT(!LLVMPointerTypeIsOpaque(type));
				IR_FALLTHROUGH;
			case LLVMArrayTypeKind:
				type = LLVMGetElementType(type);
				if (LLVMGetValueKind(op) == LLVMConstantIntValueKind) {
					index = LLVMConstIntGetSExtValue(op);
					offset += index * LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type);
				} else {
					ir_ref idx;

					if (offset) {
						ref = ir_ADD_A(ref, ir_const_addr(ctx, (uintptr_t)offset));
						offset = 0;
					}
					idx = llvm2ir_op(ctx, op, IR_ADDR);
					size = LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type);
					if (size == 1) {
						ref = ir_ADD_A(ref, idx);
					} else {
						if (ctx->ir_base[idx].op == IR_NEG) {
							idx = ctx->ir_base[idx].op1;
							ref = ir_SUB_A(ref, ir_MUL_A(
								idx,
								ir_const_addr(ctx, LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type))));
						} else {
							ref = ir_ADD_A(ref, ir_MUL_A(
								idx,
								ir_const_addr(ctx, LLVMABISizeOfType((LLVMTargetDataRef)ctx->rules, type))));
						}
					}
				}
				break;
			default:
				IR_ASSERT(0);
				return;
		}
		type_kind = LLVMGetTypeKind(type);
	}
	if (offset) {
		ref = ir_ADD_A(ref, ir_const_addr(ctx, (uintptr_t)offset));
	}
	ir_addrtab_set(ctx->binding, (uintptr_t)insn, ref);
}

static ir_ref llvm2ir_const_expr(ir_ctx *ctx, LLVMValueRef expr)
{
	LLVMOpcode opcode = LLVMGetConstOpcode(expr);

	switch (opcode) {
		case LLVMFNeg:
			return llvm2ir_unary_op(ctx, expr, IR_NEG);
		case LLVMAdd:
		case LLVMFAdd:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_ADD);
		case LLVMSub:
		case LLVMFSub:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_SUB);
		case LLVMMul:
		case LLVMFMul:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_MUL);
		case LLVMUDiv:
		case LLVMSDiv:
		case LLVMFDiv:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_DIV);
		case LLVMURem:
		case LLVMSRem:
			break;
		case LLVMShl:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_SHL);
		case LLVMLShr:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_SHR);
		case LLVMAShr:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_SAR);
		case LLVMAnd:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_AND);
		case LLVMOr:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_OR);
		case LLVMXor:
			return llvm2ir_binary_op(ctx, opcode, expr, IR_XOR);
		case LLVMTrunc:
			return llvm2ir_cast_op(ctx, expr, IR_TRUNC, opcode);
		case LLVMZExt:
			return llvm2ir_cast_op(ctx, expr, IR_ZEXT, opcode);
		case LLVMSExt:
			return llvm2ir_cast_op(ctx, expr, IR_SEXT, opcode);
		case LLVMFPTrunc:
		case LLVMFPExt:
			return llvm2ir_cast_op(ctx, expr, IR_FP2FP, opcode);
		case LLVMFPToUI:
		case LLVMFPToSI:
			return llvm2ir_cast_op(ctx, expr, IR_FP2INT, opcode);
		case LLVMUIToFP:
		case LLVMSIToFP:
			return llvm2ir_cast_op(ctx, expr, IR_INT2FP, opcode);
		case LLVMPtrToInt:
		case LLVMIntToPtr:
		case LLVMBitCast:
			return llvm2ir_cast_op(ctx, expr, IR_BITCAST, opcode);
		case LLVMICmp:
			return llvm2ir_icmp_op(ctx, expr);
		case LLVMFCmp:
			return llvm2ir_fcmp_op(ctx, expr);
		case LLVMSelect:
			return llvm2ir_cond_op(ctx, expr);
		case LLVMGetElementPtr:
			return llvm2ir_const_element_ptr(ctx, expr);
		default:
			break;
	}
	fprintf(stderr, "Unsupported LLVM expr: %d\n", opcode);
	IR_ASSERT(0);
	return 0;
}

static ir_ref llvm2ir_auto_cast(ir_ctx *ctx, ir_ref ref, ir_type src_type, ir_type type)
{
	if (IR_IS_TYPE_INT(type)) {
		if (IR_IS_TYPE_INT(src_type)) {
			if (ir_type_size[type] == ir_type_size[src_type]) {
				if (type == IR_ADDR) {
					return ref;
				} else {
					return ir_BITCAST(type, ref);
				}
			} else if (ir_type_size[type] > ir_type_size[src_type]) {
				if (IR_IS_TYPE_SIGNED(src_type)) {
					return ir_SEXT(type, ref);
				} else {
					return ir_ZEXT(type, ref);
				}
			} else if (ir_type_size[type] < ir_type_size[src_type]) {
				return ir_TRUNC(type, ref);
			}
		} else {
			// TODO: FP to INT conversion
		}
	} else if (IR_IS_TYPE_FP(type)) {
		if (IR_IS_TYPE_FP(src_type)) {
			return ir_FP2FP(type, ref);
		} else {
			return ir_INT2FP(type, ref);
		}
	}
	IR_ASSERT(0);
	return ref;
}

static void llvm2ir_bb_start(ir_ctx *ctx, LLVMBasicBlockRef bb, LLVMBasicBlockRef pred_bb)
{
	LLVMValueRef insn = LLVMGetLastInstruction(pred_bb);
	LLVMOpcode opcode = LLVMGetInstructionOpcode(insn);

	if (opcode == LLVMBr) {
		ir_ref ref = ir_addrtab_find(ctx->binding, (uintptr_t)insn);

		IR_ASSERT(ref != (ir_ref)IR_INVALID_VAL);
		if (!LLVMIsConditional(insn)) {
			ir_BEGIN(ref);
		} else {
			LLVMBasicBlockRef true_bb;

			IR_ASSERT(LLVMGetNumSuccessors(insn) == 2);
			true_bb = LLVMGetSuccessor(insn, 0); /* true branch */
			if (bb == true_bb) {
				IR_ASSERT(bb != LLVMGetSuccessor(insn, 1)); /* false branch */
				ir_IF_TRUE(ref);
			} else {
				IR_ASSERT(bb == LLVMGetSuccessor(insn, 1)); /* false branch */
				ir_IF_FALSE(ref);
			}
		}
	} else if (opcode == LLVMSwitch) {
		ir_ref ref = ir_addrtab_find(ctx->binding, (uintptr_t)insn);

		IR_ASSERT(ref != (ir_ref)IR_INVALID_VAL);
		if (LLVMGetSwitchDefaultDest(insn) == bb) {
			if (LLVMGetInstructionOpcode(LLVMGetFirstInstruction(bb)) != LLVMUnreachable) {
				ir_CASE_DEFAULT(ref);
			}
		} else  {
			uint32_t i;
			uint32_t count = LLVMGetNumOperands(insn);

			for (i = 2; i < count; i += 2) {
				if (LLVMValueAsBasicBlock(LLVMGetOperand(insn, i + 1)) == bb) {
					LLVMValueRef val = LLVMGetOperand(insn, i);
					ir_type type = llvm2ir_type(LLVMTypeOf(val));
					ir_CASE_VAL(ref, llvm2ir_op(ctx, val, type));
					break;
				}
			}
		}
	} else {
		IR_ASSERT(0);
	}
}

static void llvm2ir_set_predecessor_ref(uint32_t b, ir_ref ref, uint32_t count, uint32_t *edges, ir_ref *refs)
{
	do {
		if (*edges == b && !*refs) {
			*refs = ref;
			return;
		}
	    edges++;
	    refs++;
		count--;
	} while (count);
	IR_ASSERT(0);
}

static void llvm2ir_patch_merge(ir_ctx *ctx, ir_ref merge, ir_ref ref, uint32_t b, uint32_t *edges)
{
	ir_insn *insn = &ctx->ir_base[merge];
	ir_ref *ops = insn->ops + 1;
	uint32_t count = insn->inputs_count;

	IR_ASSERT(insn->op == IR_MERGE || insn->op == IR_LOOP_BEGIN);
	insn->op = IR_LOOP_BEGIN;
	do {
		if (*edges == b && !*ops) {
			*ops = ref;
			return;
		}
	    edges++;
	    ops++;
		count--;
	} while (count);
	IR_ASSERT(0);
}

static int llvm2ir_func(ir_ctx *ctx, LLVMValueRef func, LLVMModuleRef module)
{
	uint32_t i, cconv;
	LLVMValueRef param;
	LLVMTypeRef ftype;
	ir_type type;
	ir_ref ref;
	int ret;

	// TODO: function prototype
	ftype = LLVMGlobalGetValueType(func);
	cconv = LLVMGetFunctionCallConv(func);
	if (cconv == LLVMCCallConv || cconv == LLVMFastCallConv) {
		/* skip */
	} else if (cconv == LLVMX86FastcallCallConv) {
		ctx->flags |= IR_FASTCALL_FUNC;
	} else {
		fprintf(stderr, "Unsupported Calling Convention: %d\n", cconv);
		IR_ASSERT(0);
		return 0;
	}
	if (LLVMIsFunctionVarArg(ftype)) {
		ctx->flags |= IR_VARARG_FUNC;
	}
	ctx->ret_type = llvm2ir_type(LLVMGetReturnType(ftype));

	/* Reuse "binding" for LLVMValueRef -> ir_ref hash */
	ctx->binding = ir_mem_malloc(sizeof(ir_hashtab));
	ir_addrtab_init(ctx->binding, 256);

	ir_START();
	for (i = 0; i < LLVMCountParams(func); i++) {
		size_t name_len;
		const char *name;
		char buf[32];

		param = LLVMGetParam(func, i);
		type = llvm2ir_type(LLVMTypeOf(param));
		if (type == IR_BAD_TYPE) {
			return 0;
		}
		name = LLVMGetValueName2(param, &name_len);
		if (!name || !name_len) {
			snprintf(buf, sizeof(buf), "arg_%d", i + 1);
			name = buf;
		}
		ref = ir_PARAM(type, name, i + 1);
		ir_addrtab_set(ctx->binding, (uintptr_t)param, ref);
	}

	ret = llvm2ir_func_ex(ctx, func, module, func);

	ir_addrtab_free(ctx->binding);
	ir_mem_free(ctx->binding);
	ctx->binding = NULL;
	return ret;
}

static int llvm2ir_func_ex(ir_ctx *ctx, LLVMValueRef func, LLVMModuleRef module, LLVMValueRef root_func)
{
	uint32_t i, j, n, b, succ, count, bb_count, post_order_count, predecessor_edges_count, *post_order;
	LLVMBasicBlockRef *bbs, bb;
	LLVMValueRef insn;
	LLVMOpcode opcode;
	ir_type type;
	ir_ref ref, max_inputs_count;
	ir_hashtab bb_hash;
	ir_use_list *predecessors;
	uint32_t *predecessor_edges;
	ir_ref *inputs, *bb_starts, *predecessor_refs;
	ir_ref inline_ret = IR_UNUSED;
	ir_worklist worklist;

	/* Find LLVM Basic Blocks */
	bb_count = LLVMCountBasicBlocks(func);
	bbs = ir_mem_malloc(bb_count * sizeof(LLVMBasicBlockRef));
	LLVMGetBasicBlocks(func, bbs);
	ir_addrtab_init(&bb_hash, bb_count);
	for (i = 0; i < bb_count; i++) {
		bb = bbs[i];
		ir_addrtab_set(&bb_hash, (uintptr_t)bb, i);
	}

	/* Find proper Basic Blocks order */
	post_order = ir_mem_malloc(sizeof(uint32_t) * bb_count);
	post_order_count = 0;

	ir_worklist_init(&worklist, bb_count);
	bb = LLVMGetEntryBasicBlock(func);
	b = ir_addrtab_find(&bb_hash, (uintptr_t)bb);
	IR_ASSERT(b < bb_count);
	ir_worklist_push(&worklist, b);

	while (ir_worklist_len(&worklist) != 0) {
next:
		b = ir_worklist_peek(&worklist);
		bb = bbs[b];
		insn = LLVMGetLastInstruction(bb);
		opcode = LLVMGetInstructionOpcode(insn);
		if (opcode == LLVMBr || opcode == LLVMSwitch) {
			n = LLVMGetNumSuccessors(insn);
			for (j = 0; j < n; j++) {
				succ = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetSuccessor(insn, j));
				IR_ASSERT(succ < bb_count);
				if (ir_worklist_push(&worklist, succ)) {
					goto next;
				}
			}
		}
		ir_worklist_pop(&worklist);
		post_order[post_order_count++] = b;
	}

	/* Find LLVM BasicBlocks Predecessors */
	predecessors = ir_mem_calloc(bb_count, sizeof(ir_use_list));
	i = post_order_count;
	while (i > 0) {
		i--;
		b = post_order[i];
		bb = bbs[b];
		insn = LLVMGetLastInstruction(bb);
		opcode = LLVMGetInstructionOpcode(insn);
		if (opcode == LLVMBr || opcode == LLVMSwitch) {
			count = LLVMGetNumSuccessors(insn);
			for (j = 0; j < count; j++) {
				succ = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetSuccessor(insn, j));
				IR_ASSERT(succ < bb_count);
				if (ir_bitset_in(worklist.visited, succ)) {
					predecessors[succ].count++;
				}
			}
		}
	}

	predecessor_edges_count = 0;
	max_inputs_count = 0;
	i = post_order_count;
	while (i > 0) {
		i--;
		b = post_order[i];
		predecessors[b].refs = predecessor_edges_count;
		predecessor_edges_count += predecessors[b].count;
		max_inputs_count = IR_MAX(max_inputs_count, predecessors[b].count);
		predecessors[b].count = 0;
	}

	predecessor_edges = ir_mem_malloc(sizeof(uint32_t) * predecessor_edges_count);
	predecessor_refs = ir_mem_calloc(sizeof(ir_ref), predecessor_edges_count);
	inputs = ir_mem_malloc(sizeof(ir_ref) * max_inputs_count);
	i = post_order_count;
	while (i > 0) {
		i--;
		b = post_order[i];
		bb = bbs[b];
		insn = LLVMGetLastInstruction(bb);
		opcode = LLVMGetInstructionOpcode(insn);
		if (opcode == LLVMBr || opcode == LLVMSwitch) {
			count = LLVMGetNumSuccessors(insn);
			for (j = 0; j < count; j++) {
				succ = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetSuccessor(insn, j));
				IR_ASSERT(succ < bb_count);
				if (ir_bitset_in(worklist.visited, succ)) {
					predecessor_edges[predecessors[succ].refs + predecessors[succ].count++] = b;
				}
			}
		}
	}

	ir_worklist_free(&worklist);

	/* Process all reachable basic blocks in proper order */
	ir_bitset visited = ir_bitset_malloc(bb_count);
	bb_starts = ir_mem_malloc(bb_count * sizeof(ir_ref));
	while (post_order_count) {
		i = post_order[--post_order_count];
		bb = bbs[i];
		count = predecessors[i].count;
		if (count == 1) {
			llvm2ir_bb_start(ctx, bb, bbs[predecessor_edges[predecessors[i].refs]]);
			if (!ctx->control) {
				/* eliminte unreachable CASE_DEFAULT block */
				continue;
			}
		} else if (count > 1) {
			ir_MERGE_N(count, predecessor_refs + predecessors[i].refs); /* MERGE may be converted to LOOP_BEGIN later */
		} else if (i != 0) {
			ir_BEGIN(IR_UNUSED); /* unreachable block */
		}
		bb_starts[i] = ctx->control;
		ir_bitset_incl(visited, i);

		for (insn = LLVMGetFirstInstruction(bb); insn; insn = LLVMGetNextInstruction(insn)) {
			opcode = LLVMGetInstructionOpcode(insn);
			switch (opcode) {
				case LLVMRet:
					if (func != root_func) {
						ir_END_PHI_list(inline_ret, llvm2ir_retval(ctx, insn));
					} else if (ctx->control) {
						llvm2ir_ret(ctx, insn);
					}
					break;
				case LLVMBr:
					if (!LLVMIsConditional(insn)) {
						ref = llvm2ir_jmp(ctx, insn);
						b = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetSuccessor(insn, 0));
						IR_ASSERT(b < bb_count);
						if (predecessors[b].count > 1) {
							if (ir_bitset_in(visited, b)) {
								llvm2ir_patch_merge(ctx, bb_starts[b], ref, i, predecessor_edges + predecessors[b].refs);
								ctx->ir_base[ref].op = IR_LOOP_END;
							} else {
								llvm2ir_set_predecessor_ref(i, ref, predecessors[b].count,
									predecessor_edges + predecessors[b].refs, predecessor_refs + predecessors[b].refs);
							}
						}
					} else {
						ref = llvm2ir_if(ctx, insn);
						b = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetSuccessor(insn, 0)); /* true branch */
						IR_ASSERT(b < bb_count);
						if (predecessors[b].count > 1) {
							ir_IF_TRUE(ref);
							if (ir_bitset_in(visited, b)) {
								llvm2ir_patch_merge(ctx, bb_starts[b], ir_LOOP_END(), i, predecessor_edges + predecessors[b].refs);
							} else {
								llvm2ir_set_predecessor_ref(i, ir_END(), predecessors[b].count,
									predecessor_edges + predecessors[b].refs, predecessor_refs + predecessors[b].refs);
							}
						} else {
							IR_ASSERT(!ir_bitset_in(visited, b));
						}
						b = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetSuccessor(insn, 1)); /* false branch */
						IR_ASSERT(b < bb_count);
						if (predecessors[b].count > 1) {
							ir_IF_FALSE(ref);
							if (ir_bitset_in(visited, b)) {
								llvm2ir_patch_merge(ctx, bb_starts[b], ir_LOOP_END(), i, predecessor_edges + predecessors[b].refs);
							} else {
								llvm2ir_set_predecessor_ref(i, ir_END(), predecessors[b].count,
									predecessor_edges + predecessors[b].refs, predecessor_refs + predecessors[b].refs);
							}
						} else {
							IR_ASSERT(!ir_bitset_in(visited, b));
						}
					}
					break;
				case LLVMSwitch:
					ref = llvm2ir_switch(ctx, insn);
					b = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetSwitchDefaultDest(insn));
					IR_ASSERT(b < bb_count);
					if (predecessors[b].count > 1) {
						ir_CASE_DEFAULT(ref);
						if (ir_bitset_in(visited, b)) {
							llvm2ir_patch_merge(ctx, bb_starts[b], ir_LOOP_END(), i, predecessor_edges + predecessors[b].refs);
						} else {
							llvm2ir_set_predecessor_ref(i, ir_END(), predecessors[b].count,
								predecessor_edges + predecessors[b].refs, predecessor_refs + predecessors[b].refs);
						}
					} else {
						IR_ASSERT(!ir_bitset_in(visited, b));
					}
					count = LLVMGetNumOperands(insn);
					for (j = 2; j < count; j += 2) {
						b = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMValueAsBasicBlock(LLVMGetOperand(insn, j + 1)));
						IR_ASSERT(b < bb_count);
						if (predecessors[b].count > 1) {
							LLVMValueRef val = LLVMGetOperand(insn, j);
							ir_type type = llvm2ir_type(LLVMTypeOf(val));
							ir_CASE_VAL(ref, llvm2ir_op(ctx, val, type));
							if (ir_bitset_in(visited, b)) {
								llvm2ir_patch_merge(ctx, bb_starts[b], ir_LOOP_END(), i, predecessor_edges + predecessors[b].refs);
							} else {
								llvm2ir_set_predecessor_ref(i, ir_END(), predecessors[b].count,
									predecessor_edges + predecessors[b].refs, predecessor_refs + predecessors[b].refs);
							}
						} else {
							IR_ASSERT(!ir_bitset_in(visited, b));
						}
					}
					break;
				case LLVMIndirectBr:
					// TODO:
					IR_ASSERT(0 && "NIY LLVMIndirectBr");
					break;
				case LLVMUnreachable:
					ir_UNREACHABLE();
					break;
				case LLVMFNeg:
					llvm2ir_unary_op(ctx, insn, IR_NEG);
					break;
				case LLVMAdd:
				case LLVMFAdd:
					llvm2ir_binary_op(ctx, opcode, insn, IR_ADD);
					break;
				case LLVMSub:
				case LLVMFSub:
					llvm2ir_binary_op(ctx, opcode, insn, IR_SUB);
					break;
				case LLVMMul:
				case LLVMFMul:
					llvm2ir_binary_op(ctx, opcode, insn, IR_MUL);
					break;
				case LLVMUDiv:
				case LLVMSDiv:
				case LLVMFDiv:
					llvm2ir_binary_op(ctx, opcode, insn, IR_DIV);
					break;
				case LLVMURem:
				case LLVMSRem:
					llvm2ir_binary_op(ctx, opcode, insn, IR_MOD);
					break;
				case LLVMShl:
					llvm2ir_binary_op(ctx, opcode, insn, IR_SHL);
					break;
				case LLVMLShr:
					llvm2ir_binary_op(ctx, opcode, insn, IR_SHR);
					break;
				case LLVMAShr:
					llvm2ir_binary_op(ctx, opcode, insn, IR_SAR);
					break;
				case LLVMAnd:
					llvm2ir_binary_op(ctx, opcode, insn, IR_AND);
					break;
				case LLVMOr:
					llvm2ir_binary_op(ctx, opcode, insn, IR_OR);
					break;
				case LLVMXor:
					llvm2ir_binary_op(ctx, opcode, insn, IR_XOR);
					break;
				case LLVMAlloca:
					llvm2ir_alloca(ctx, insn);
					break;
				case LLVMLoad:
					llvm2ir_load(ctx, insn);
					break;
				case LLVMStore:
					llvm2ir_store(ctx, insn);
					break;
				case LLVMTrunc:
					llvm2ir_cast_op(ctx, insn, IR_TRUNC, opcode);
					break;
				case LLVMZExt:
					llvm2ir_cast_op(ctx, insn, IR_ZEXT, opcode);
					break;
				case LLVMSExt:
					llvm2ir_cast_op(ctx, insn, IR_SEXT, opcode);
					break;
				case LLVMFPTrunc:
				case LLVMFPExt:
					llvm2ir_cast_op(ctx, insn, IR_FP2FP, opcode);
					break;
				case LLVMFPToUI:
				case LLVMFPToSI:
					llvm2ir_cast_op(ctx, insn, IR_FP2INT, opcode);
					break;
				case LLVMUIToFP:
				case LLVMSIToFP:
					llvm2ir_cast_op(ctx, insn, IR_INT2FP, opcode);
					break;
				case LLVMPtrToInt:
				case LLVMIntToPtr:
				case LLVMBitCast:
					llvm2ir_cast_op(ctx, insn, IR_BITCAST, opcode);
					break;
				case LLVMICmp:
					llvm2ir_icmp_op(ctx, insn);
					break;
				case LLVMFCmp:
					llvm2ir_fcmp_op(ctx, insn);
					break;
				case LLVMPHI:
					count = LLVMCountIncoming(insn);
					memset(inputs, 0, count * sizeof(ir_ref));
					if (LLVMGetTypeKind(LLVMTypeOf(insn)) == LLVMStructTypeKind) {
						type = llvm2ir_overflow_type(LLVMTypeOf(insn));
					} else {
						type = llvm2ir_type(LLVMTypeOf(insn));
					}
					ref = ir_PHI_N(type, count, inputs);
					ir_addrtab_set(ctx->binding, (uint64_t)insn, ref);
					break;
				case LLVMSelect:
					llvm2ir_cond_op(ctx, insn);
					break;
				case LLVMCall:
					llvm2ir_call(ctx, insn, module, root_func);
					break;
				case LLVMGetElementPtr:
					llvm2ir_element_ptr(ctx, insn);
					break;
				case LLVMFreeze:
					llvm2ir_freeze(ctx, insn);
					break;
				case LLVMVAArg:
					llvm2ir_va_arg(ctx, insn);
					break;
				case LLVMExtractValue:
					if (llvm2ir_extract(ctx, insn)) {
						break;
					}
					IR_FALLTHROUGH;
				default:
					fprintf(stderr, "Unsupported LLVM insn: %d\n", opcode);
					IR_ASSERT(0);
					return 0;
			}
		}
	}

	/* Backpatch PHIs */
	for (i = 0; i < bb_count; i++) {
		ir_ref phi;
		uint32_t k;

		bb = bbs[i];
		count = predecessors[i].count;
		if (count <= 1) continue;
		IR_ASSERT(ctx->ir_base[bb_starts[i]].op == IR_MERGE || ctx->ir_base[bb_starts[i]].op == IR_LOOP_BEGIN);
		for (insn = LLVMGetFirstInstruction(bb);
				insn && LLVMGetInstructionOpcode(insn) == LLVMPHI;
				insn = LLVMGetNextInstruction(insn)) {
			phi = ir_addrtab_find(ctx->binding, (uint64_t)insn);
			IR_ASSERT(phi != (ir_ref)IR_INVALID_VAL);
			IR_ASSERT(ctx->ir_base[phi].op == IR_PHI);
			IR_ASSERT(LLVMCountIncoming(insn) == count);
			for (j = 0; j < count; j++) {
				LLVMValueRef op = LLVMGetIncomingValue(insn, j);
				uint32_t b = ir_addrtab_find(&bb_hash, (uintptr_t)LLVMGetIncomingBlock(insn, j));

				IR_ASSERT(b < bb_count);
				ref = llvm2ir_op(ctx, op, ctx->ir_base[phi].type);
				for (k = 0; k < count; k++) {
					if (predecessor_edges[predecessors[i].refs + k] == b) {
						ir_PHI_SET_OP(phi, k + 1, ref);
					}
				}
			}
		}
	}

	ir_mem_free(visited);
	ir_mem_free(post_order);
	ir_mem_free(predecessor_refs);
	ir_mem_free(bb_starts);
	ir_addrtab_free(&bb_hash);
	ir_mem_free(bbs);
	ir_mem_free(predecessors);
	ir_mem_free(predecessor_edges);
	ir_mem_free(inputs);

	if (func != root_func) {
		ir_ref phi = ir_PHI_list(inline_ret);
		if (phi) {
			return phi;
		}
	}

	return 1;
}

static int llvm2ir_external_func(ir_loader *loader, const char *name, LLVMValueRef func)
{
	uint32_t i, count, cconv, flags = 0;
	LLVMTypeRef ftype;
	ir_type ret_type;
	uint8_t *param_types;

	ftype = LLVMGlobalGetValueType(func);
	cconv = LLVMGetFunctionCallConv(func);
	if (cconv == LLVMCCallConv || cconv == LLVMFastCallConv) {
		/* skip */
	} else if (cconv == LLVMX86FastcallCallConv) {
		flags |= IR_FASTCALL_FUNC;
	} else {
		fprintf(stderr, "Unsupported Calling Convention: %d\n", cconv);
		IR_ASSERT(0);
		return 0;
	}
	if (LLVMIsFunctionVarArg(ftype)) {
		flags |= IR_VARARG_FUNC;
	}
	ret_type = llvm2ir_type(LLVMGetReturnType(ftype));

	count = LLVMCountParams(func);
	param_types = alloca(count * sizeof(ir_type));
	for (i = 0; i < count; i++) {
		param_types[i] = llvm2ir_type(LLVMTypeOf(LLVMGetParam(func, i)));
	}

	return loader->external_func_dcl(loader, name, flags, ret_type, count, param_types);
}

static int llvm2ir_forward_func(ir_loader *loader, const char *name, LLVMValueRef func, LLVMBool is_static)
{
	uint32_t i, count, cconv, flags = 0;
	LLVMTypeRef ftype;
	ir_type ret_type;
	uint8_t *param_types;

	ftype = LLVMGlobalGetValueType(func);
	cconv = LLVMGetFunctionCallConv(func);
	if (cconv == LLVMCCallConv || cconv == LLVMFastCallConv) {
		/* skip */
	} else if (cconv == LLVMX86FastcallCallConv) {
		flags |= IR_FASTCALL_FUNC;
	} else {
		fprintf(stderr, "Unsupported Calling Convention: %d\n", cconv);
		IR_ASSERT(0);
		return 0;
	}
	if (LLVMIsFunctionVarArg(ftype)) {
		flags |= IR_VARARG_FUNC;
	}
	if (is_static) {
		flags |= IR_STATIC;
	}
	ret_type = llvm2ir_type(LLVMGetReturnType(ftype));

	count = LLVMCountParams(func);
	param_types = alloca(count * sizeof(ir_type));
	for (i = 0; i < count; i++) {
		param_types[i] = llvm2ir_type(LLVMTypeOf(LLVMGetParam(func, i)));
	}

	return loader->forward_func_dcl(loader, name, flags, ret_type, count, param_types);
}

static int llvm2ir_data(ir_loader *loader, LLVMTargetDataRef target_data, LLVMTypeRef type, LLVMValueRef op, size_t pos)
{
	LLVMTypeRef el_type;
	LLVMValueRef el;
	LLVMBool lose;
	ir_type t;
	ir_val val;
	uint32_t i, len;
	const char *name;
	size_t name_len;
	char buf[256];
	void *p = NULL;
	size_t offset, el_size;
	LLVMValueKind kind = LLVMGetValueKind(op);
	LLVMOpcode opcode;

	switch (kind) {
		case LLVMConstantIntValueKind:
			t = llvm2ir_type(type);
			IR_ASSERT(IR_IS_TYPE_INT(t));
			if (IR_IS_TYPE_SIGNED(t)) {
				val.i64 = LLVMConstIntGetSExtValue(op);
			} else {
				val.i64 = LLVMConstIntGetZExtValue(op);
			}
			switch (ir_type_size[t]) {
				case 1: p = &val.i8;  break;
				case 2: p = &val.i16; break;
				case 4: p = &val.i32; break;
				case 8: p = &val.i64; break;
				default:
					IR_ASSERT(0);
					break;
			}
			return loader->sym_data(loader, t, 1, p);
		case LLVMConstantFPValueKind:
			t = llvm2ir_type(type);
			if (t == IR_DOUBLE) {
				val.d = LLVMConstRealGetDouble(op, &lose);
				return loader->sym_data(loader, t, 1, &val.d);
			} else {
				IR_ASSERT(t == IR_FLOAT);
				val.f = (float)LLVMConstRealGetDouble(op, &lose);
				val.u32_hi = 0;
				return loader->sym_data(loader, t, 1, &val.f);
			}
		case LLVMConstantPointerNullValueKind:
			val.addr = 0;
			return loader->sym_data(loader, IR_ADDR, 1, &val.addr);
		case LLVMConstantArrayValueKind:
		case LLVMConstantDataArrayValueKind:
			el_type = LLVMGetElementType(type);
			el_size = LLVMABISizeOfType(target_data, el_type);
			len = LLVMGetArrayLength(type);
			offset = 0;
			for (i = 0; i < len; i++) {
				if (i > 0 && loader->sym_data_pad) {
					loader->sym_data_pad(loader, pos + offset);
				}
				el = LLVMGetAggregateElement(op, i);
				if (!llvm2ir_data(loader, target_data, el_type, el, pos)) {
					return 0;
				}
				pos += el_size;
			}
			return 1;
		case LLVMConstantStructValueKind:
			len = LLVMCountStructElementTypes(type);
			for (i = 0; i < len; i++) {
				offset = LLVMOffsetOfElement(target_data, type, i);
				if (i > 0 && loader->sym_data_pad) {
					loader->sym_data_pad(loader, pos + offset);
				}
				el_type = LLVMStructGetTypeAtIndex(type, i);
				el = LLVMGetAggregateElement(op, i);
				if (!llvm2ir_data(loader, target_data, el_type, el, pos + offset)) {
					return 0;
				}
			}
			return 1;
		case LLVMConstantAggregateZeroValueKind:
			switch (LLVMGetTypeKind(type)) {
				case LLVMIntegerTypeKind:
				case LLVMFloatTypeKind:
				case LLVMDoubleTypeKind:
				case LLVMPointerTypeKind:
				case LLVMFunctionTypeKind:
				case LLVMLabelTypeKind:
					t = llvm2ir_type(type);
					val.u64 = 0;
					return loader->sym_data(loader, t, 1, &val.u64);
				default:
					// TODO: use bigger type if possible
					len = LLVMABISizeOfType(target_data, type);
					if (!len) {
						/* an empty structure */
						return 1;
					}
					val.u64 = 0;
					return loader->sym_data(loader, IR_U8, len, &val.u64);
			}
		case LLVMGlobalVariableValueKind:
			// TODO: resolve variable address
			name = LLVMGetValueName2(op, &name_len);
			name = llvm2ir_sym_name(buf, name, name_len);
			if (!name) {
				return 0;
			}
			return loader->sym_data_ref(loader, IR_SYM, name, 0);
		case LLVMFunctionValueKind:
			// TODO: function prototype
			// TODO: resolve function address
			name = LLVMGetValueName2(op, &name_len);
			name = llvm2ir_sym_name(buf, name, name_len);
			if (!name) {
				return 0;
			}
			return loader->sym_data_ref(loader, IR_FUNC, name, 0);
		case LLVMConstantExprValueKind:
			opcode = LLVMGetConstOpcode(op);
			if (opcode == LLVMPtrToInt) {
				LLVMValueRef op0 = LLVMGetOperand(op, 0);

				t = llvm2ir_type(LLVMTypeOf(op0));
				IR_ASSERT(IR_IS_TYPE_INT(t));
				if (ir_type_size[t] == ir_type_size[IR_ADDR]) {
					op = op0;
					opcode = LLVMGetConstOpcode(op);
				}
			}
			if (opcode == LLVMGetElementPtr) {
				LLVMValueRef op0 = LLVMGetOperand(op, 0);

				if (LLVMGetValueKind(op0) == LLVMGlobalVariableValueKind) {
					uintptr_t offset = llvm2ir_const_element_ptr_offset(target_data, op);
					name = LLVMGetValueName2(op0, &name_len);
					name = llvm2ir_sym_name(buf, name, name_len);
					if (!name) {
						return 0;
					}
					return loader->sym_data_ref(loader, IR_SYM, name, offset);
				}
			} else if (opcode == LLVMIntToPtr) {
				LLVMValueRef op0 = LLVMGetOperand(op, 0);

				if (LLVMGetValueKind(op0) == LLVMConstantIntValueKind) {
					t = llvm2ir_type(LLVMTypeOf(op0));
					IR_ASSERT(IR_IS_TYPE_INT(t));
					if (IR_IS_TYPE_SIGNED(t)) {
						val.i64 = LLVMConstIntGetSExtValue(op0);
					} else {
						val.i64 = LLVMConstIntGetZExtValue(op0);
					}
					return loader->sym_data(loader, IR_ADDR, 1, &val);
				}
			}
			fprintf(stderr, "Unsupported constant expr: %d\n", (int)opcode);
			IR_ASSERT(0);
			return 0;
		case LLVMUndefValueValueKind:
		case LLVMPoisonValueValueKind:
			// TODO: ???
			if (LLVMGetTypeKind(type) == LLVMArrayTypeKind) {
				el_type = LLVMGetElementType(type);
				len = LLVMGetArrayLength(type);
				t = llvm2ir_type(el_type);
				val.i64 = 0;
				return loader->sym_data(loader, t, len, &val.i64);
			} else {
				t = llvm2ir_type(type);
				val.i64 = 0;
				return loader->sym_data(loader, t, 1, &val.i64);
			}
		default:
			fprintf(stderr, "Unsupported LLVM value kind: %d\n", kind);
			IR_ASSERT(0);
			return 0;
	}

	return 1;
}

static int ir_load_llvm_module(ir_loader *loader, LLVMModuleRef module)
{
	ir_ctx ctx;
	LLVMValueRef sym, func;
	LLVMTargetDataRef target_data = LLVMGetModuleDataLayout(module);
	const char *name;
	size_t name_len;
	char buf[256];

	if (loader->init_module
	 && !loader->init_module(loader,
			LLVMGetModuleIdentifier(module, &name_len),
			LLVMGetSourceFileName(module, &name_len),
			LLVMGetTarget(module))) {
		IR_ASSERT(0);
		return 0;
	}

	if (loader->external_func_dcl) {
		for (func = LLVMGetFirstFunction(module); func; func = LLVMGetNextFunction(func)) {
			LLVMLinkage linkage;
			bool is_external = 0;
			bool is_static = 0;

			if (!LLVMIsDeclaration(func)) continue;
			linkage = LLVMGetLinkage(func);
			name = LLVMGetValueName2(func, &name_len);
			if (STR_START(name, name_len, "llvm.")) continue;
			switch (linkage) {
				case LLVMExternalLinkage:
					is_external = 1;
					break;
				case LLVMInternalLinkage:
				case LLVMPrivateLinkage:
					is_static = 1;
					break;
				default:
					fprintf(stderr, "Unsupported LLVM linkage: %d\n", linkage);
					IR_ASSERT(0);
			}
			if (is_external) {
				if (!llvm2ir_external_func(loader, name, func)) {
					fprintf(stderr, "Cannot resolve external LLVM function \"%s\"\n", name);
					return 0;
				}
			} else {
				if (loader->forward_func_dcl
				 && !llvm2ir_forward_func(loader, name, func, is_static)) {
					fprintf(stderr, "Cannot declare forward LLVM function \"%s\"\n", name);
					return 0;
				}
			}
		}
	}

	if (loader->forward_func_dcl) {
		for (func = LLVMGetFirstFunction(module); func; func = LLVMGetNextFunction(func)) {
			LLVMLinkage linkage;
			bool is_static = 0;

			if (LLVMIsDeclaration(func)) continue;
			linkage = LLVMGetLinkage(func);
			name = LLVMGetValueName2(func, &name_len);
			switch (linkage) {
				case LLVMExternalLinkage:
				case LLVMAvailableExternallyLinkage:
					break;
				case LLVMInternalLinkage:
				case LLVMPrivateLinkage:
					is_static = 1;
					name = llvm2ir_sym_name(buf, name, name_len);
					if (!name) {
						fprintf(stderr, "Bad LLVM function name \"%s\"\n", LLVMGetValueName2(func, &name_len));
						return 0;
					}
					break;
				default:
					fprintf(stderr, "Unsupported LLVM linkage: %d\n", linkage);
					IR_ASSERT(0);
			}
			if (!llvm2ir_forward_func(loader, name, func, is_static)) {
				fprintf(stderr, "Cannot compile forward LLVM function \"%s\"\n", name);
				return 0;
			}
		}
	}

	for (sym = LLVMGetFirstGlobal(module); sym; sym = LLVMGetNextGlobal(sym)) {
		LLVMLinkage linkage = LLVMGetLinkage(sym);
		LLVMValueRef init = LLVMGetInitializer(sym);
		bool is_external = 0;
		uint32_t flags = 0;

		IR_ASSERT(!LLVMIsThreadLocal(sym));
		switch (linkage) {
			case LLVMExternalLinkage:
				if (!init) {
					is_external = 1;
				}
				break;
			case LLVMInternalLinkage:
			case LLVMPrivateLinkage:
				flags |= IR_STATIC;
				break;
			default:
				fprintf(stderr, "Unsupported LLVM linkage: %d\n", linkage);
				IR_ASSERT(0);
		}
		name = LLVMGetValueName2(sym, &name_len);
		if (is_external) {
			if (LLVMIsGlobalConstant(sym)) {
				flags |= IR_CONST;
			}
			name = llvm2ir_sym_name(buf, name, name_len);
			if (loader->external_sym_dcl
			 && !loader->external_sym_dcl(loader, name, flags)) {
				fprintf(stderr, "Cannot compile external LLVM symbol \"%s\"\n", name);
				return 0;
			}
		} else {
			if (loader->sym_dcl) {
				LLVMTypeRef type;
				size_t size;
				char buf[256];

				type = LLVMGlobalGetValueType(sym);
				size = LLVMABISizeOfType(target_data, type);

				if (flags & IR_STATIC) {
					name = llvm2ir_sym_name(buf, name, name_len);
					if (!name) {
						fprintf(stderr, "Bad LLVM symbol name \"%s\"\n", LLVMGetValueName2(sym, &name_len));
						return 0;
					}
				}
				if (LLVMIsGlobalConstant(sym)) {
					flags |= IR_CONST;
				}
				if (init && LLVMGetValueKind(init) != LLVMConstantAggregateZeroValueKind) {
					flags |= IR_INITIALIZED;
					if (LLVMIsConstantString(init)) {
						flags |= IR_CONST_STRING;
					}
				}
				if (!loader->sym_dcl(loader, name, flags, size)) {
					fprintf(stderr, "Cannot compile LLVM symbol \"%s\"\n", name);
					return 0;
				}
				if (flags & IR_CONST_STRING) {
					size_t len;
					const char *str = LLVMGetAsString(init, &len);

					if (!loader->sym_data_str(loader, str, len)
					 || !loader->sym_data_end(loader, flags)) {
						fprintf(stderr, "Cannot compile LLVM symbol \"%s\"\n", name);
						return 0;
					}
				} else if (flags & IR_INITIALIZED) {
					if (!llvm2ir_data(loader, target_data, type, init, 0)
					 || !loader->sym_data_end(loader, flags)) {
						fprintf(stderr, "Cannot compile LLVM symbol \"%s\"\n", name);
						return 0;
					}
				}
			}
		}
	}

	for (func = LLVMGetFirstFunction(module); func; func = LLVMGetNextFunction(func)) {
		if (LLVMIsDeclaration(func)) continue;
		name = LLVMGetValueName2(func, &name_len);
		if (!loader->func_init(loader, &ctx, name)) {
			fprintf(stderr, "Cannot compile function \"%s\"\n", name);
			return 0;
		}
		switch (LLVMGetLinkage(func)) {
			case LLVMInternalLinkage:
			case LLVMPrivateLinkage:
				ctx.flags |= IR_STATIC;
				name = llvm2ir_sym_name(buf, name, name_len);
				if (!name) {
					fprintf(stderr, "Bad LLVM function name \"%s\"\n", LLVMGetValueName2(func, &name_len));
					return 0;
				}
				break;
			default:
				break;
		}
		ctx.rules = (void*)target_data;
		if (!llvm2ir_func(&ctx, func, module)) {
			ctx.rules = NULL;
			ir_free(&ctx);
			fprintf(stderr, "Cannot compile function \"%s\"\n", name);
			return 0;
		}
		ctx.rules = NULL;

		if (!loader->func_process(loader, &ctx, name)) {
			ir_free(&ctx);
			fprintf(stderr, "Cannot compile function \"%s\"\n", name);
			return 0;
		}

		ir_free(&ctx);
	}

	return 1;
}

int ir_load_llvm_bitcode(ir_loader *loader, const char *filename)
{
	LLVMMemoryBufferRef memory_buffer;
	LLVMModuleRef module;
	LLVMBool ret;
	char *message;

	if (LLVMCreateMemoryBufferWithContentsOfFile(filename, &memory_buffer, &message)) {
		fprintf(stderr, "Cannot open '%s': %s\n", filename, message);
		free(message);
		return 0;
	}
	ret = LLVMParseBitcodeInContext2(LLVMGetGlobalContext(), memory_buffer, &module);
	LLVMDisposeMemoryBuffer(memory_buffer);
	if (ret) {
		fprintf(stderr, "Cannot parse LLVM bitcode\n");
		return 0;
	}
	if (!ir_load_llvm_module(loader, module)) {
		LLVMDisposeModule(module);
		fprintf(stderr, "Cannot convert LLVM to IR\n");
		return 0;
	}
	LLVMDisposeModule(module);

	return 1;
}

int ir_load_llvm_asm(ir_loader *loader, const char *filename)
{
	LLVMMemoryBufferRef memory_buffer;
	LLVMModuleRef module;
	LLVMBool ret;
	char *message;

	if (LLVMCreateMemoryBufferWithContentsOfFile(filename, &memory_buffer, &message)) {
		fprintf(stderr, "Cannot open '%s': %s\n", filename, message);
		free(message);
		return 0;
	}
	ret = LLVMParseIRInContext(LLVMGetGlobalContext(), memory_buffer, &module, &message);
	if (ret) {
		fprintf(stderr, "Cannot parse LLVM file: %s\n", message);
		free(message);
		return 0;
	}
	if (!ir_load_llvm_module(loader, module)) {
		LLVMDisposeModule(module);
		fprintf(stderr, "Cannot convert LLVM to IR\n");
		return 0;
	}
	LLVMDisposeModule(module);

	return 1;
}