Bug 1130618: Ensure float32 coercion of inputs to Float32 MConstant; r=luke

--HG--
extra : rebase_source : 9513ab5cecb9da7aade20a332504f6865eedf660

js/src/asmjs/AsmJSModule.h

@@ -147,9 +147,6 @@ class AsmJSNumLit
     static AsmJSNumLit Create(Which w, Value v) {
         AsmJSNumLit lit;
         lit.which_ = w;
-        // Force float32 coercion, as the caller may have not done it.
-        if (w == Float)
-            v = Float32Value(v.toNumber());
         lit.value.scalar_ = v;
         MOZ_ASSERT(!lit.isSimd());
         return lit;

js/src/jit-test/tests/asm.js/bug1126251.js

@@ -1,5 +1,6 @@
 load(libdir + "asm.js");
 
+// Bug 1126251
 var v = asmLink(asmCompile('global', `
     "use asm";
     var frd = global.Math.fround;
@@ -34,3 +35,16 @@ var v = asmLink(asmCompile('global', `
 `), this)();
 
 assertEq(v, NaN);
+
+// Bug 1130618
+var v = asmLink(asmCompile('global', `
+    "use asm";
+    var float32x4 = global.SIMD.float32x4;
+    var splat = float32x4.splat;
+    function e() {
+        return +splat(.1e+71).x;
+    }
+    return e;
+`), this)();
+
+assertEq(v, Infinity);

js/src/jit/MIR.cpp

@@ -629,6 +629,7 @@ MConstant *
 MConstant::NewTypedValue(TempAllocator &alloc, const Value &v, MIRType type, CompilerConstraintList *constraints)
 {
     MOZ_ASSERT(!IsSimdType(type));
+    MOZ_ASSERT_IF(type == MIRType_Float32, v.toDouble() == double(float(v.toDouble())));
     MConstant *constant = new(alloc) MConstant(v, constraints);
     constant->setResultType(type);
     return constant;
@@ -637,6 +638,8 @@ MConstant::NewTypedValue(TempAllocator &alloc, const Value &v, MIRType type, Com
 MConstant *
 MConstant::NewAsmJS(TempAllocator &alloc, const Value &v, MIRType type)
 {
+    if (type == MIRType_Float32)
+        return NewTypedValue(alloc, Float32Value(v.toNumber()), type);
     return NewTypedValue(alloc, v, type);
 }