Fix DoubleStackSlot-to-DoubleStackSlot moves on ia32. Unify platform-independent code.

BUG=173907

Review URL: https://codereview.chromium.org/12207063

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13617 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/lithium-codegen-arm.cc

@@ -568,30 +568,13 @@ MemOperand LCodeGen::ToMemOperand(LOperand* op) const {
   ASSERT(!op->IsRegister());
   ASSERT(!op->IsDoubleRegister());
   ASSERT(op->IsStackSlot() || op->IsDoubleStackSlot());
-  int index = op->index();
-  if (index >= 0) {
-    // Local or spill slot. Skip the frame pointer, function, and
-    // context in the fixed part of the frame.
-    return MemOperand(fp, -(index + 3) * kPointerSize);
-  } else {
-    // Incoming parameter. Skip the return address.
-    return MemOperand(fp, -(index - 1) * kPointerSize);
-  }
+  return MemOperand(fp, StackSlotOffset(op->index()));
 }
 
 
 MemOperand LCodeGen::ToHighMemOperand(LOperand* op) const {
   ASSERT(op->IsDoubleStackSlot());
-  int index = op->index();
-  if (index >= 0) {
-    // Local or spill slot. Skip the frame pointer, function, context,
-    // and the first word of the double in the fixed part of the frame.
-    return MemOperand(fp, -(index + 3) * kPointerSize + kPointerSize);
-  } else {
-    // Incoming parameter. Skip the return address and the first word of
-    // the double.
-    return MemOperand(fp, -(index - 1) * kPointerSize + kPointerSize);
-  }
+  return MemOperand(fp, StackSlotOffset(op->index()) + kPointerSize);
 }
 
 

src/ia32/lithium-codegen-ia32.cc

@@ -549,23 +549,13 @@ Operand LCodeGen::ToOperand(LOperand* op) const {
   if (op->IsRegister()) return Operand(ToRegister(op));
   if (op->IsDoubleRegister()) return Operand(ToDoubleRegister(op));
   ASSERT(op->IsStackSlot() || op->IsDoubleStackSlot());
-  int index = op->index();
-  if (index >= 0) {
-    // Local or spill slot. Skip the frame pointer, function, and
-    // context in the fixed part of the frame.
-    return Operand(ebp, -(index + 3) * kPointerSize);
-  } else {
-    // Incoming parameter. Skip the return address.
-    return Operand(ebp, -(index - 1) * kPointerSize);
-  }
+  return Operand(ebp, StackSlotOffset(op->index()));
 }
 
 
 Operand LCodeGen::HighOperand(LOperand* op) {
   ASSERT(op->IsDoubleStackSlot());
-  int index = op->index();
-  int offset = (index >= 0) ? index + 3 : index - 1;
-  return Operand(ebp, -offset * kPointerSize);
+  return Operand(ebp, StackSlotOffset(op->index()) + kPointerSize);
 }
 
 

src/lithium.cc

@@ -257,6 +257,18 @@ int ElementsKindToShiftSize(ElementsKind elements_kind) {
 }
 
 
+int StackSlotOffset(int index) {
+  if (index >= 0) {
+    // Local or spill slot. Skip the frame pointer, function, and
+    // context in the fixed part of the frame.
+    return -(index + 3) * kPointerSize;
+  } else {
+    // Incoming parameter. Skip the return address.
+    return -(index - 1) * kPointerSize;
+  }
+}
+
+
 LChunk::LChunk(CompilationInfo* info, HGraph* graph)
     : spill_slot_count_(0),
       info_(info),

src/lithium.h

@@ -709,6 +709,7 @@ class LChunk: public ZoneObject {
 
 
 int ElementsKindToShiftSize(ElementsKind elements_kind);
+int StackSlotOffset(int index);
 
 enum NumberUntagDMode {
   NUMBER_CANDIDATE_IS_SMI,

src/mips/lithium-codegen-mips.cc

@@ -528,30 +528,13 @@ MemOperand LCodeGen::ToMemOperand(LOperand* op) const {
   ASSERT(!op->IsRegister());
   ASSERT(!op->IsDoubleRegister());
   ASSERT(op->IsStackSlot() || op->IsDoubleStackSlot());
-  int index = op->index();
-  if (index >= 0) {
-    // Local or spill slot. Skip the frame pointer, function, and
-    // context in the fixed part of the frame.
-    return MemOperand(fp, -(index + 3) * kPointerSize);
-  } else {
-    // Incoming parameter. Skip the return address.
-    return MemOperand(fp, -(index - 1) * kPointerSize);
-  }
+  return MemOperand(fp, StackSlotOffset(op->index()));
 }
 
 
 MemOperand LCodeGen::ToHighMemOperand(LOperand* op) const {
   ASSERT(op->IsDoubleStackSlot());
-  int index = op->index();
-  if (index >= 0) {
-    // Local or spill slot. Skip the frame pointer, function, context,
-    // and the first word of the double in the fixed part of the frame.
-    return MemOperand(fp, -(index + 3) * kPointerSize + kPointerSize);
-  } else {
-    // Incoming parameter. Skip the return address and the first word of
-    // the double.
-    return MemOperand(fp, -(index - 1) * kPointerSize + kPointerSize);
-  }
+  return MemOperand(fp, StackSlotOffset(op->index()) + kPointerSize);
 }
 
 

src/x64/lithium-codegen-x64.cc

@@ -464,15 +464,7 @@ Operand LCodeGen::ToOperand(LOperand* op) const {
   // Does not handle registers. In X64 assembler, plain registers are not
   // representable as an Operand.
   ASSERT(op->IsStackSlot() || op->IsDoubleStackSlot());
-  int index = op->index();
-  if (index >= 0) {
-    // Local or spill slot. Skip the frame pointer, function, and
-    // context in the fixed part of the frame.
-    return Operand(rbp, -(index + 3) * kPointerSize);
-  } else {
-    // Incoming parameter. Skip the return address.
-    return Operand(rbp, -(index - 1) * kPointerSize);
-  }
+  return Operand(rbp, StackSlotOffset(op->index()));
 }