From b1e7adaad5c2ff3de5158d6c36f6ddc8cb7864fb Mon Sep 17 00:00:00 2001
From: Sean Stangl <sstangl@mozilla.com>
Date: Thu, 7 Nov 2013 15:19:55 -0800
Subject: [PATCH] Bug 936234 - Inline n-Ary Math.min and Math.max. r=shu

---
 js/src/jit/MCallOptimize.cpp | 34 +++++++++++++++++++---------------
 1 file changed, 19 insertions(+), 15 deletions(-)

diff --git a/js/src/jit/MCallOptimize.cpp b/js/src/jit/MCallOptimize.cpp
index 706f70e5727..82b7e527adb 100644
--- a/js/src/jit/MCallOptimize.cpp
+++ b/js/src/jit/MCallOptimize.cpp
@@ -883,32 +883,36 @@ IonBuilder::inlineMathFRound(CallInfo &callInfo)
 IonBuilder::InliningStatus
 IonBuilder::inlineMathMinMax(CallInfo &callInfo, bool max)
 {
-    if (callInfo.argc() != 2 || callInfo.constructing())
+    if (callInfo.argc() < 2 || callInfo.constructing())
         return InliningStatus_NotInlined;
 
     MIRType returnType = getInlineReturnType();
     if (!IsNumberType(returnType))
         return InliningStatus_NotInlined;
 
-    MIRType arg0Type = callInfo.getArg(0)->type();
-    if (!IsNumberType(arg0Type))
-        return InliningStatus_NotInlined;
-    MIRType arg1Type = callInfo.getArg(1)->type();
-    if (!IsNumberType(arg1Type))
-        return InliningStatus_NotInlined;
+    for (unsigned i = 0; i < callInfo.argc(); i++) {
+        MIRType argType = callInfo.getArg(i)->type();
+        if (!IsNumberType(argType))
+            return InliningStatus_NotInlined;
 
-    if (returnType == MIRType_Int32 &&
-        (arg0Type == MIRType_Double || arg1Type == MIRType_Double))
-    {
-        // We would need to inform TI, if we happen to return a double.
-        return InliningStatus_NotInlined;
+        // We would need to inform TI if we happen to return a double.
+        if (returnType == MIRType_Int32 && IsFloatingPointType(argType))
+            return InliningStatus_NotInlined;
     }
 
     callInfo.unwrapArgs();
 
-    MMinMax *ins = MMinMax::New(callInfo.getArg(0), callInfo.getArg(1), returnType, max);
-    current->add(ins);
-    current->push(ins);
+    // Chain N-1 MMinMax instructions to compute the MinMax.
+    MMinMax *last = MMinMax::New(callInfo.getArg(0), callInfo.getArg(1), returnType, max);
+    current->add(last);
+
+    for (unsigned i = 2; i < callInfo.argc(); i++) {
+        MMinMax *ins = MMinMax::New(last, callInfo.getArg(i), returnType, max);
+        current->add(ins);
+        last = ins;
+    }
+
+    current->push(last);
     return InliningStatus_Inlined;
 }