Fix mozilla regress-398085-01 failure on windows.

Make sure that all stack pages are mapped before accessing them.

R=jkummerow@chromium.org

Review URL: https://chromiumcodereview.appspot.com/20607005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16007 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/ia32/lithium-codegen-ia32.cc

@@ -137,6 +137,16 @@ void LCodeGen::Comment(const char* format, ...) {
 }
 
 
+#ifdef _MSC_VER
+void LCodeGen::MakeSureStackPagesMapped(int offset) {
+  const int kPageSize = 4 * KB;
+  for (offset -= kPageSize; offset > 0; offset -= kPageSize) {
+    __ mov(Operand(esp, offset), eax);
+  }
+}
+#endif
+
+
 bool LCodeGen::GeneratePrologue() {
   ASSERT(is_generating());
 
@@ -226,6 +236,9 @@ bool LCodeGen::GeneratePrologue() {
     } else {
       if (FLAG_debug_code) {
         __ sub(Operand(esp), Immediate(slots * kPointerSize));
+#ifdef _MSC_VER
+        MakeSureStackPagesMapped(slots * kPointerSize);
+#endif
         __ push(eax);
         __ mov(Operand(eax), Immediate(slots));
         Label loop;
@@ -238,15 +251,7 @@ bool LCodeGen::GeneratePrologue() {
       } else {
         __ sub(Operand(esp), Immediate(slots * kPointerSize));
 #ifdef _MSC_VER
-        // On windows, you may not access the stack more than one page below
-        // the most recently mapped page. To make the allocated area randomly
-        // accessible, we write to each page in turn (the value is irrelevant).
-        const int kPageSize = 4 * KB;
-        for (int offset = slots * kPointerSize - kPageSize;
-             offset > 0;
-             offset -= kPageSize) {
-          __ mov(Operand(esp, offset), eax);
-        }
+        MakeSureStackPagesMapped(slots * kPointerSize);
 #endif
       }
 

src/ia32/lithium-codegen-ia32.h

@@ -408,6 +408,14 @@ class LCodeGen BASE_EMBEDDED {
   int X87ArrayIndex(X87Register reg);
   int x87_st2idx(int pos);
 
+#ifdef _MSC_VER
+  // On windows, you may not access the stack more than one page below
+  // the most recently mapped page. To make the allocated area randomly
+  // accessible, we write an arbitrary value to each page in range
+  // esp + offset - page_size .. esp in turn.
+  void MakeSureStackPagesMapped(int offset);
+#endif
+
   Zone* zone_;
   LPlatformChunk* const chunk_;
   MacroAssembler* const masm_;

src/x64/lithium-codegen-x64.cc

@@ -120,6 +120,16 @@ void LCodeGen::Comment(const char* format, ...) {
 }
 
 
+#ifdef _MSC_VER
+void LCodeGen::MakeSureStackPagesMapped(int offset) {
+  const int kPageSize = 4 * KB;
+  for (offset -= kPageSize; offset > 0; offset -= kPageSize) {
+    __ movq(Operand(rsp, offset), rax);
+  }
+}
+#endif
+
+
 bool LCodeGen::GeneratePrologue() {
   ASSERT(is_generating());
 
@@ -169,6 +179,9 @@ bool LCodeGen::GeneratePrologue() {
   if (slots > 0) {
     if (FLAG_debug_code) {
       __ subq(rsp, Immediate(slots * kPointerSize));
+#ifdef _MSC_VER
+      MakeSureStackPagesMapped(slots * kPointerSize);
+#endif
       __ push(rax);
       __ Set(rax, slots);
       __ movq(kScratchRegister, kSlotsZapValue, RelocInfo::NONE64);
@@ -182,15 +195,7 @@ bool LCodeGen::GeneratePrologue() {
     } else {
       __ subq(rsp, Immediate(slots * kPointerSize));
 #ifdef _MSC_VER
-      // On windows, you may not access the stack more than one page below
-      // the most recently mapped page. To make the allocated area randomly
-      // accessible, we write to each page in turn (the value is irrelevant).
-      const int kPageSize = 4 * KB;
-      for (int offset = slots * kPointerSize - kPageSize;
-           offset > 0;
-           offset -= kPageSize) {
-        __ movq(Operand(rsp, offset), rax);
-      }
+      MakeSureStackPagesMapped(slots * kPointerSize);
 #endif
     }
 

src/x64/lithium-codegen-x64.h

@@ -345,6 +345,13 @@ class LCodeGen BASE_EMBEDDED {
   void DoStoreKeyedExternalArray(LStoreKeyed* instr);
   void DoStoreKeyedFixedDoubleArray(LStoreKeyed* instr);
   void DoStoreKeyedFixedArray(LStoreKeyed* instr);
+#ifdef _MSC_VER
+  // On windows, you may not access the stack more than one page below
+  // the most recently mapped page. To make the allocated area randomly
+  // accessible, we write an arbitrary value to each page in range
+  // rsp + offset - page_size .. rsp in turn.
+  void MakeSureStackPagesMapped(int offset);
+#endif
 
   Zone* zone_;
   LPlatformChunk* const chunk_;