Partial ia32 implementation of optimized try/catch (by Kevin Millikin)

src/ia32/macro-assembler-ia32.cc

Index: src/ia32/macro-assembler-ia32.cc
diff --git a/src/ia32/macro-assembler-ia32.cc b/src/ia32/macro-assembler-ia32.cc
index 9c5f31e2cf4c5d00af038c08f8852ffb0dceba4d..e10ddcd3b33f218c80808814d2f0b046d98b0ce8 100644
--- a/src/ia32/macro-assembler-ia32.cc
+++ b/src/ia32/macro-assembler-ia32.cc
@@ -893,8 +893,9 @@ void MacroAssembler::JumpToHandlerEntry() {
   shr(edx, StackHandler::kKindWidth);
   mov(edx, FieldOperand(ebx, edx, times_4, FixedArray::kHeaderSize));
   SmiUntag(edx);
-  lea(edi, FieldOperand(edi, edx, times_1, Code::kHeaderSize));
-  jmp(edi);
+  // Preserve code object in edi for the optimizer handler.
+  lea(edx, FieldOperand(edi, edx, times_1, Code::kHeaderSize));
+  jmp(edx);
 }
 
 
@@ -911,10 +912,14 @@ void MacroAssembler::Throw(Register value) {
   if (!value.is(eax)) {
     mov(eax, value);
   }
-  // Drop the stack pointer to the top of the top handler.
+
+  // Get the handler address.
   ExternalReference handler_address(Isolate::kHandlerAddress, isolate());
-  mov(esp, Operand::StaticVariable(handler_address));
-  // Restore the next handler.
+  mov(ecx, Operand::StaticVariable(handler_address));
+
+  // Drop the stack pointer to the top of the top handler and restore the
+  // next handler.
+  mov(esp, ecx);
   pop(Operand::StaticVariable(handler_address));
 
   // Remove the code object and state, compute the handler address in edi.