MIPS: Refactoring after 'MIPS: split api call stubs into accessor and function call stubs'.

Change stack handling to clarify the usage of reserved MIPS argument slots for mips32.

BUG=

Review URL: https://codereview.chromium.org/867183003

Cr-Commit-Position: refs/heads/master@{#26279}

src/mips/code-stubs-mips.cc

@@ -4845,13 +4845,10 @@ static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
 // from handle and propagates exceptions.  Restores context.  stack_space
 // - space to be unwound on exit (includes the call JS arguments space and
 // the additional space allocated for the fast call).
-static void CallApiFunctionAndReturn(MacroAssembler* masm,
-                                     Register function_address,
-                                     ExternalReference thunk_ref,
-                                     int stack_space,
-                                     MemOperand* stack_space_operand,
-                                     MemOperand return_value_operand,
-                                     MemOperand* context_restore_operand) {
+static void CallApiFunctionAndReturn(
+    MacroAssembler* masm, Register function_address,
+    ExternalReference thunk_ref, int stack_space, int32_t stack_space_offset,
+    MemOperand return_value_operand, MemOperand* context_restore_operand) {
   Isolate* isolate = masm->isolate();
   ExternalReference next_address =
       ExternalReference::handle_scope_next_address(isolate);
@@ -4945,13 +4942,15 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
   if (restore_context) {
     __ lw(cp, *context_restore_operand);
   }
-  if (stack_space_operand != NULL) {
-    __ lw(s0, *stack_space_operand);
+  if (stack_space_offset != kInvalidStackOffset) {
+    // ExitFrame contains four MIPS argument slots after DirectCEntryStub call
+    // so this must be accounted for.
+    __ lw(s0, MemOperand(sp, stack_space_offset + kCArgsSlotsSize));
   } else {
     __ li(s0, Operand(stack_space));
   }
   __ LeaveExitFrame(false, s0, !restore_context, EMIT_RETURN,
-                    stack_space_operand != NULL);
+                    stack_space_offset != kInvalidStackOffset);
 
   __ bind(&promote_scheduled_exception);
   {
@@ -5082,15 +5081,13 @@ static void CallApiFunctionStubHelper(MacroAssembler* masm,
   }
   MemOperand return_value_operand(fp, return_value_offset * kPointerSize);
   int stack_space = 0;
-  MemOperand is_construct_call_operand =
-      MemOperand(sp, 4 * kPointerSize + kCArgsSlotsSize);
-  MemOperand* stack_space_operand = &is_construct_call_operand;
+  int32_t stack_space_offset = 4 * kPointerSize;
   if (argc.is_immediate()) {
     stack_space = argc.immediate() + FCA::kArgsLength + 1;
-    stack_space_operand = NULL;
+    stack_space_offset = kInvalidStackOffset;
   }
   CallApiFunctionAndReturn(masm, api_function_address, thunk_ref, stack_space,
-                           stack_space_operand, return_value_operand,
+                           stack_space_offset, return_value_operand,
                            &context_restore_operand);
 }
 
@@ -5139,7 +5136,7 @@ void CallApiGetterStub::Generate(MacroAssembler* masm) {
   ExternalReference thunk_ref =
       ExternalReference::invoke_accessor_getter_callback(isolate());
   CallApiFunctionAndReturn(masm, api_function_address, thunk_ref,
-                           kStackUnwindSpace, NULL,
+                           kStackUnwindSpace, kInvalidStackOffset,
                            MemOperand(fp, 6 * kPointerSize), NULL);
 }
 

src/mips/constants-mips.h

@@ -924,6 +924,7 @@ class Instruction {
 // C/C++ argument slots size.
 const int kCArgSlotCount = 4;
 const int kCArgsSlotsSize = kCArgSlotCount * Instruction::kInstrSize;
+const int kInvalidStackOffset = -1;
 // JS argument slots size.
 const int kJSArgsSlotsSize = 0 * Instruction::kInstrSize;
 // Assembly builtins argument slots size.

src/mips64/code-stubs-mips64.cc

@@ -4887,13 +4887,10 @@ static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
 // from handle and propagates exceptions.  Restores context.  stack_space
 // - space to be unwound on exit (includes the call JS arguments space and
 // the additional space allocated for the fast call).
-static void CallApiFunctionAndReturn(MacroAssembler* masm,
-                                     Register function_address,
-                                     ExternalReference thunk_ref,
-                                     int stack_space,
-                                     MemOperand* stack_space_operand,
-                                     MemOperand return_value_operand,
-                                     MemOperand* context_restore_operand) {
+static void CallApiFunctionAndReturn(
+    MacroAssembler* masm, Register function_address,
+    ExternalReference thunk_ref, int stack_space, int32_t stack_space_offset,
+    MemOperand return_value_operand, MemOperand* context_restore_operand) {
   Isolate* isolate = masm->isolate();
   ExternalReference next_address =
       ExternalReference::handle_scope_next_address(isolate);
@@ -4987,13 +4984,14 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
   if (restore_context) {
     __ ld(cp, *context_restore_operand);
   }
-  if (stack_space_operand != NULL) {
-    __ lw(s0, *stack_space_operand);
+  if (stack_space_offset != kInvalidStackOffset) {
+    DCHECK(kCArgsSlotsSize == 0);
+    __ ld(s0, MemOperand(sp, stack_space_offset));
   } else {
     __ li(s0, Operand(stack_space));
   }
   __ LeaveExitFrame(false, s0, !restore_context, EMIT_RETURN,
-                    stack_space_operand != NULL);
+                    stack_space_offset != kInvalidStackOffset);
   __ bind(&promote_scheduled_exception);
   {
     FrameScope frame(masm, StackFrame::INTERNAL);
@@ -5123,14 +5121,13 @@ static void CallApiFunctionStubHelper(MacroAssembler* masm,
   }
   MemOperand return_value_operand(fp, return_value_offset * kPointerSize);
   int stack_space = 0;
-  MemOperand is_construct_call_operand = MemOperand(sp, 4 * kPointerSize);
-  MemOperand* stack_space_operand = &is_construct_call_operand;
+  int32_t stack_space_offset = 4 * kPointerSize;
   if (argc.is_immediate()) {
     stack_space = argc.immediate() + FCA::kArgsLength + 1;
-    stack_space_operand = NULL;
+    stack_space_offset = kInvalidStackOffset;
   }
   CallApiFunctionAndReturn(masm, api_function_address, thunk_ref, stack_space,
-                           stack_space_operand, return_value_operand,
+                           stack_space_offset, return_value_operand,
                            &context_restore_operand);
 }
 
@@ -5179,7 +5176,7 @@ void CallApiGetterStub::Generate(MacroAssembler* masm) {
   ExternalReference thunk_ref =
       ExternalReference::invoke_accessor_getter_callback(isolate());
   CallApiFunctionAndReturn(masm, api_function_address, thunk_ref,
-                           kStackUnwindSpace, NULL,
+                           kStackUnwindSpace, kInvalidStackOffset,
                            MemOperand(fp, 6 * kPointerSize), NULL);
 }
 

src/mips64/constants-mips64.h

@@ -942,6 +942,7 @@ const int kCArgSlotCount = (kMipsAbi == kN64) ? 0 : 4;
 // TODO(plind): find all usages and remove the needless instructions for n64.
 const int kCArgsSlotsSize = kCArgSlotCount * Instruction::kInstrSize * 2;
 
+const int kInvalidStackOffset = -1;
 const int kBranchReturnOffset = 2 * Instruction::kInstrSize;
 
 } }   // namespace v8::internal