feat(stdlib): Add Float32/Float64 constants for infinity/nan (#720)

Co-authored-by: Philip Blair <[email protected]>

compiler/test/stdlib/float32.test.gr

@@ -14,3 +14,10 @@ assert !gt(5.0f, 5.0f)
 assert !gte(5.0f, 22.0f)
 assert !lt(5.0f, -17.0f)
 assert !lte(5.0f, 4.0f)
+
+// smoke test:
+assert gt(infinity, 100000000.f)
+// test infinity-specific semantics:
+assert toNumber(infinity) == toNumber(infinity)
+assert toNumber(infinity) == (toNumber(infinity) - 1)
+assert nan != nan

compiler/test/stdlib/float64.test.gr

@@ -14,3 +14,9 @@ assert !gt(5.0d, 5.0d)
 assert !gte(5.0d, 22.0d)
 assert !lt(5.0d, -17.0d)
 assert !lte(5.0d, 4.0d)
+
+// smoke test:
+assert gt(infinity, 100000000.d)
+// test infinity-specific semantics:
+assert toNumber(infinity) == (toNumber(infinity) - 1)
+assert nan != nan

stdlib/float32.gr

@@ -74,3 +74,21 @@ export let gte = (x: Float32, y: Float32) => {
   let y = WasmF32.load(WasmI32.fromGrain(y), 8n)
   WasmF32.ge(x, y)
 }
+
+// floating-point constants:
+
+@disableGC
+let makeInfinity = () => {
+  let ptr = newFloat32(WasmF32.reinterpretI32(0b01111111100000000000000000000000n))
+  WasmI32.toGrain(ptr) : Float32
+}
+
+export let infinity = makeInfinity()
+
+@disableGC
+let makeNaN = () => {
+  let ptr = newFloat32(WasmF32.reinterpretI32(0b01111111100000000000000000000001n))
+  WasmI32.toGrain(ptr) : Float32
+}
+
+export let nan = makeNaN()

stdlib/float64.gr

@@ -74,3 +74,21 @@ export let gte = (x: Float64, y: Float64) => {
   let y = WasmF64.load(WasmI32.fromGrain(y), 8n)
   WasmF64.ge(x, y)
 }
+
+// floating-point constants:
+
+@disableGC
+let makeInfinity = () => {
+  let ptr = newFloat64(WasmF64.reinterpretI64(0b0111111111110000000000000000000000000000000000000000000000000000N))
+  WasmI32.toGrain(ptr) : Float64
+}
+
+export let infinity = makeInfinity()
+
+@disableGC
+let makeNaN = () => {
+  let ptr = newFloat64(WasmF64.reinterpretI64(0b0111111111110000000000000000000000000000000000000000000000000001N))
+  WasmI32.toGrain(ptr) : Float64
+}
+
+export let nan = makeNaN()