API call code refactoring (ia32).

src/ia32/stub-cache-ia32.cc

Index: src/ia32/stub-cache-ia32.cc
===================================================================
--- src/ia32/stub-cache-ia32.cc	(revision 5829)
+++ src/ia32/stub-cache-ia32.cc	(working copy)
@@ -499,8 +499,7 @@
   // it's not controlled by GC.
   const int kApiStackSpace = 4;
 
-  __ PrepareCallApiFunction(argc + kFastApiCallArguments + 1,
-                            kApiArgc + kApiStackSpace);
+  __ PrepareCallApiFunction(kApiArgc + kApiStackSpace, ebx);

[antonm, 2010/11/16 14:32:26]

nice that the bug was spotted.  but I am slightly uneasy that our tests didn't
catch it.  can you add a test that demonstrates the presence of the bug?

[SeRya, 2010/11/16 14:53:28]

I don't see any bug. This line changed not to fix a bug but because signature of
PrepareCallApiFunction had changed. It doesn't receive number of JS references
anymore since now that references are removed in TryCallApiFunctionAndReturn.

 
   __ mov(ApiParameterOperand(1), eax);  // v8::Arguments::implicit_args_.
   __ add(Operand(eax), Immediate(argc * kPointerSize));
@@ -518,7 +517,7 @@
   // garbage collection but instead return the allocation failure
   // object.
   MaybeObject* result =
-      masm->TryCallApiFunctionAndReturn(&fun, kApiArgc + kApiStackSpace);
+      masm->TryCallApiFunctionAndReturn(&fun, argc + kFastApiCallArguments + 1);
   if (result->IsFailure()) {
     *failure = Failure::cast(result);
     return false;
@@ -1109,7 +1108,7 @@
   const int kStackSpace = 5;
   const int kApiArgc = 2;
 
-  __ PrepareCallApiFunction(kStackSpace, kApiArgc);
+  __ PrepareCallApiFunction(kApiArgc, eax);
   __ mov(ApiParameterOperand(0), ebx);  // name.
   __ add(Operand(ebx), Immediate(kPointerSize));
   __ mov(ApiParameterOperand(1), ebx);  // arguments pointer.
@@ -1118,7 +1117,7 @@
   // already generated).  Do not allow the assembler to perform a
   // garbage collection but instead return the allocation failure
   // object.
-  MaybeObject* result = masm()->TryCallApiFunctionAndReturn(&fun, kApiArgc);
+  MaybeObject* result = masm()->TryCallApiFunctionAndReturn(&fun, kStackSpace);
   if (result->IsFailure()) {
     *failure = Failure::cast(result);
     return false;
@@ -2169,7 +2168,10 @@
 
       if (depth != kInvalidProtoDepth) {
         __ IncrementCounter(&Counters::call_const_fast_api, 1);
-        ReserveSpaceForFastApiCall(masm(), eax);
+
+        // Allocate space for v8::Arguments implicit values. Must be initialized
+        // before call any runtime function.

[antonm, 2010/11/16 14:32:26]

before call <to> any runtime

[SeRya, 2010/11/16 14:53:28]

Done.

+        __ sub(Operand(esp), Immediate(kFastApiCallArguments * kPointerSize));
       }
 
       // Check that the maps haven't changed.
@@ -2249,6 +2251,12 @@
 
   if (depth != kInvalidProtoDepth) {
     Failure* failure;
+    // Move the return address on top of the stack.
+    __ mov(eax, Operand(esp, 3 * kPointerSize));
+    __ mov(Operand(esp, 0 * kPointerSize), eax);
+
+    // esp[2 * kPointerSize] is uninitialized, esp[3 * kPointerSize] contains
+    // duplicate of return address and will be overwritten.
     bool success = GenerateFastApiCall(masm(), optimization, argc, &failure);
     if (!success) {
       return failure;
@@ -2260,7 +2268,7 @@
   // Handle call cache miss.
   __ bind(&miss);
   if (depth != kInvalidProtoDepth) {
-    FreeSpaceForFastApiCall(masm(), eax);
+    __ add(Operand(esp), Immediate(kFastApiCallArguments * kPointerSize));
   }
   __ bind(&miss_in_smi_check);
   Object* obj;