From 0e8b83129e71712f0beefd2a9ee4b7ff324894c9 Mon Sep 17 00:00:00 2001
From: Benjamin Bouvier <bbouvier@mozilla.com>
Date: Wed, 11 Sep 2013 02:10:17 -0700
Subject: [PATCH] Bug 900257: Inline Math.fround in IonMonkey; r=sstangl

---
 js/src/jit/IonBuilder.h      |  1 +
 js/src/jit/MCallOptimize.cpp | 30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/js/src/jit/IonBuilder.h b/js/src/jit/IonBuilder.h
index 42ef30965ca..8dbc0286c90 100644
--- a/js/src/jit/IonBuilder.h
+++ b/js/src/jit/IonBuilder.h
@@ -516,6 +516,7 @@ class IonBuilder : public MIRGenerator
     InliningStatus inlineMathPow(CallInfo &callInfo);
     InliningStatus inlineMathRandom(CallInfo &callInfo);
     InliningStatus inlineMathImul(CallInfo &callInfo);
+    InliningStatus inlineMathFRound(CallInfo &callInfo);
     InliningStatus inlineMathFunction(CallInfo &callInfo, MMathFunction::Function function);
 
     // String natives.
diff --git a/js/src/jit/MCallOptimize.cpp b/js/src/jit/MCallOptimize.cpp
index 086add0fdc4..3fdd8471de0 100644
--- a/js/src/jit/MCallOptimize.cpp
+++ b/js/src/jit/MCallOptimize.cpp
@@ -9,6 +9,7 @@
 #include "builtin/ParallelArray.h"
 #include "builtin/TestingFunctions.h"
 #include "jit/IonBuilder.h"
+#include "jit/Lowering.h"
 #include "jit/MIR.h"
 #include "jit/MIRGraph.h"
 
@@ -55,6 +56,8 @@ IonBuilder::inlineNativeCall(CallInfo &callInfo, JSNative native)
         return inlineMathRandom(callInfo);
     if (native == js::math_imul)
         return inlineMathImul(callInfo);
+    if (native == js::math_fround)
+        return inlineMathFRound(callInfo);
     if (native == js::math_sin)
         return inlineMathFunction(callInfo, MMathFunction::Sin);
     if (native == js::math_cos)
@@ -811,6 +814,33 @@ IonBuilder::inlineMathImul(CallInfo &callInfo)
     return InliningStatus_Inlined;
 }
 
+IonBuilder::InliningStatus
+IonBuilder::inlineMathFRound(CallInfo &callInfo)
+{
+    if (!LIRGenerator::allowFloat32Optimizations())
+        return InliningStatus_NotInlined;
+
+    if (callInfo.argc() != 1 || callInfo.constructing())
+        return InliningStatus_NotInlined;
+
+    // MIRType can't be Float32, as this point, as getInlineReturnType uses JSVal types
+    // to infer the returned MIR type.
+    MIRType returnType = getInlineReturnType();
+    if (!IsNumberType(returnType))
+        return InliningStatus_NotInlined;
+
+    MIRType arg = callInfo.getArg(0)->type();
+    if (!IsNumberType(arg))
+        return InliningStatus_NotInlined;
+
+    callInfo.unwrapArgs();
+
+    MToFloat32 *ins = MToFloat32::New(callInfo.getArg(0));
+    current->add(ins);
+    current->push(ins);
+    return InliningStatus_Inlined;
+}
+
 IonBuilder::InliningStatus
 IonBuilder::inlineMathMinMax(CallInfo &callInfo, bool max)
 {