Supports FrameLookup vm test on MIPS

runtime/vm/assembler_mips.cc

Index: runtime/vm/assembler_mips.cc
===================================================================
--- runtime/vm/assembler_mips.cc	(revision 21219)
+++ runtime/vm/assembler_mips.cc	(working copy)
@@ -169,6 +169,21 @@
 }
 
 
+void Assembler::BranchOnCondition(Register rd, Label* l, Condition c) {
+  switch (c) {
+    case EQ:
+      beq(rd, ZR, l);
+      break;
+    case NE:
+      bne(rd, ZR, l);
+      break;
+    default:
+      UNIMPLEMENTED();
+      break;
+  }
+}
+
+
 void Assembler::LoadClassId(Register result, Register object) {
   ASSERT(RawObject::kClassIdTagBit == 16);
   ASSERT(RawObject::kClassIdTagSize == 16);
@@ -204,20 +219,48 @@
 }
 
 
-void Assembler::EnterStubFrame() {
-  addiu(SP, SP, Immediate(-3 * kWordSize));
-  sw(ZR, Address(SP, 2 * kWordSize));  // PC marker is 0 in stubs.
-  sw(RA, Address(SP, 1 * kWordSize));
-  sw(FP, Address(SP, 0 * kWordSize));
-  mov(FP, SP);
+void Assembler::EnterStubFrame(bool uses_pp) {
+  if (uses_pp) {
+    addiu(SP, SP, Immediate(-4 * kWordSize));
+    sw(ZR, Address(SP, 3 * kWordSize));  // PC marker is 0 in stubs.
+    sw(RA, Address(SP, 2 * kWordSize));
+    sw(PP, Address(SP, 1 * kWordSize));
+    sw(FP, Address(SP, 0 * kWordSize));
+    mov(FP, SP);
+    // Setup pool pointer for this stub.
+    Label next;
+    bal(&next);
+    delay_slot()->mov(T0, RA);
+
+    const intptr_t object_pool_pc_dist =
+        Instructions::HeaderSize() - Instructions::object_pool_offset() +
+        CodeSize();
+
+    Bind(&next);
+    lw(PP, Address(T0, -object_pool_pc_dist));
+  } else {
+    addiu(SP, SP, Immediate(-3 * kWordSize));
+    sw(ZR, Address(SP, 2 * kWordSize));  // PC marker is 0 in stubs.
+    sw(RA, Address(SP, 1 * kWordSize));
+    sw(FP, Address(SP, 0 * kWordSize));
+    mov(FP, SP);
+  }
 }
 
 
-void Assembler::LeaveStubFrame() {
-  mov(SP, FP);
-  lw(RA, Address(SP, 1 * kWordSize));
-  lw(FP, Address(SP, 0 * kWordSize));
-  addiu(SP, SP, Immediate(3 * kWordSize));
+void Assembler::LeaveStubFrame(bool uses_pp) {
+  if (uses_pp) {
+    mov(SP, FP);

[regis, 2013/04/10 20:53:00]

You can factorize this mov.

[zra, 2013/04/10 21:59:05]

Done.

+    lw(RA, Address(SP, 2 * kWordSize));
+    lw(PP, Address(SP, 1 * kWordSize));
+    lw(FP, Address(SP, 0 * kWordSize));
+    addiu(SP, SP, Immediate(4 * kWordSize));
+  } else {
+    mov(SP, FP);
+    lw(RA, Address(SP, 1 * kWordSize));
+    lw(FP, Address(SP, 0 * kWordSize));
+    addiu(SP, SP, Immediate(3 * kWordSize));
+  }
 }
 
 
@@ -250,15 +293,16 @@
   // the PC at this sw instruction.
   Bind(&next);
 
+  // Save PC in frame for fast identification of corresponding code.
+  sw(T0, Address(SP, 3 * kWordSize));

[regis, 2013/04/10 20:53:00]

You could save this store if offset != 0:

if (offset == 0) {
  sw(T0, Address(SP, 3 * kWordSize));
} else {
  // Adjust ...

[zra, 2013/04/10 21:59:05]

Done.

+
   if (offset != 0) {
-    // Adjust PC for any intrinsic code that could have been generated
+    // Adjust saved PC for any intrinsic code that could have been generated
     // before a frame is created.
-    addiu(T0, T0, Immediate(-offset));
+    AddImmediate(T1, T0, -offset);
+    sw(T1, Address(SP, 3 * kWordSize));
   }
 
-  // Save PC in frame for fast identification of corresponding code.
-  sw(T0, Address(SP, 3 * kWordSize));
-
   // Set FP to the saved previous FP.
   addiu(FP, SP, Immediate(kWordSize));
 
@@ -266,7 +310,7 @@
   lw(PP, Address(T0, -object_pool_pc_dist));
 
   // Reserve space for locals.
-  addiu(SP, SP, Immediate(-frame_size));
+  AddImmediate(SP, -frame_size);
 }
 
 
@@ -285,7 +329,7 @@
 void Assembler::ReserveAlignedFrameSpace(intptr_t frame_space) {
   // Reserve space for arguments and align frame before entering
   // the C++ world.
-  addiu(SP, SP, Immediate(-frame_space));
+  AddImmediate(SP, -frame_space);
   if (OS::ActivationFrameAlignment() > 0) {
     LoadImmediate(TMP1, ~(OS::ActivationFrameAlignment() - 1));
     and_(SP, SP, TMP1);