Out-of-line constant pool on Arm: Stage 3 - Set Constant Pool Pointer on Function Entry

src/arm/macro-assembler-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 584 matching lines @@
       StoreBufferOverflowStub(fp_mode);
   CallStub(&store_buffer_overflow);
   pop(lr);
   bind(&done);
   if (and_then == kReturnAtEnd) {
     Ret();
   }
 }
 
 
+void MacroAssembler::PushFixedFrame(Register marker_reg) {
+  ASSERT(!marker_reg.is_valid() || marker_reg.code() < pp.code());

[Rodolph Perfetta, 2013/11/27 20:09:41]

marker_reg.code() < cp.code()

[rmcilroy, 2013/11/28 11:32:26]

Good catch, thanks!  Done.

+  stm(db_w, sp, (marker_reg.is_valid() ? marker_reg.bit() : 0) |
+                cp.bit() |
+                (FLAG_enable_ool_constant_pool ? pp.bit() : 0) |
+                fp.bit() |
+                lr.bit());
+}
+
+
+void MacroAssembler::PopFixedFrame(Register marker_reg) {
+  ASSERT(!marker_reg.is_valid() || marker_reg.code() < pp.code());

[Rodolph Perfetta, 2013/11/27 20:09:41]

ditto.

[rmcilroy, 2013/11/28 11:32:26]

Done.

+  ldm(ia_w, sp, (marker_reg.is_valid() ? marker_reg.bit() : 0) |
+                cp.bit() |
+                (FLAG_enable_ool_constant_pool ? pp.bit() : 0) |
+                fp.bit() |
+                lr.bit());
+}
+
+
 // Push and pop all registers that can hold pointers.
 void MacroAssembler::PushSafepointRegisters() {
   // Safepoints expect a block of contiguous register values starting with r0:
   ASSERT(((1 << kNumSafepointSavedRegisters) - 1) == kSafepointSavedRegisters);
   // Safepoints expect a block of kNumSafepointRegisters values on the
   // stack, so adjust the stack for unsaved registers.
   const int num_unsaved = kNumSafepointRegisters - kNumSafepointSavedRegisters;
   ASSERT(num_unsaved >= 0);
   sub(sp, sp, Operand(num_unsaved * kPointerSize));
   stm(db_w, sp, kSafepointSavedRegisters);
@@ skipping 248 matching lines @@
     const LowDwVfpRegister loc = LowDwVfpRegister::from_code(dst.code());
     vmov(loc.low(), src);
   } else {
     vmov(dst, VmovIndexLo, src);
   }
 }
 
 
 void MacroAssembler::Prologue(PrologueFrameMode frame_mode) {
   if (frame_mode == BUILD_STUB_FRAME) {
-    stm(db_w, sp, cp.bit() | fp.bit() | lr.bit());
+    PushFixedFrame();
     Push(Smi::FromInt(StackFrame::STUB));
     // Adjust FP to point to saved FP.
     add(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp));
   } else {
     PredictableCodeSizeScope predictible_code_size_scope(
         this, kNoCodeAgeSequenceLength * Assembler::kInstrSize);
     // The following three instructions must remain together and unmodified
     // for code aging to work properly.
     if (isolate()->IsCodePreAgingActive()) {
       // Pre-age the code.
       Code* stub = Code::GetPreAgedCodeAgeStub(isolate());
       add(r0, pc, Operand(-8));
       ldr(pc, MemOperand(pc, -4));
       emit_code_stub_address(stub);
     } else {
-      stm(db_w, sp, r1.bit() | cp.bit() | fp.bit() | lr.bit());
-      nop(ip.code());
+      PushFixedFrame(r1);
+      if (FLAG_enable_ool_constant_pool) {
+        ldr(pp, FieldMemOperand(r1, JSFunction::kConstantPoolOffset));
+      } else {
+        nop(ip.code());
+      }
       // Adjust FP to point to saved FP.
       add(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp));
     }
   }
 }
 
 
 void MacroAssembler::EnterFrame(StackFrame::Type type) {
   // r0-r3: preserved
-  stm(db_w, sp, cp.bit() | fp.bit() | lr.bit());
+  PushFixedFrame();
   mov(ip, Operand(Smi::FromInt(type)));
   push(ip);
   mov(ip, Operand(CodeObject()));
   push(ip);
   // Adjust FP to point to saved FP.
   add(fp, sp,
       Operand(StandardFrameConstants::kFixedFrameSizeFromFp + kPointerSize));
 }
 
 
 void MacroAssembler::LeaveFrame(StackFrame::Type type) {
   // r0: preserved
   // r1: preserved
   // r2: preserved
 
   // Drop the execution stack down to the frame pointer and restore
-  // the caller frame pointer and return address.
-  mov(sp, fp);
-  ldm(ia_w, sp, fp.bit() | lr.bit());
+  // the caller frame pointer, return address and constant pool pointer
+  // (if FLAG_enable_ool_constant_pool).
+  if (FLAG_enable_ool_constant_pool) {
+    add(sp, fp, Operand(StandardFrameConstants::kConstantPoolOffset));
+    ldm(ia_w, sp, pp.bit() | fp.bit() | lr.bit());
+  } else {
+    mov(sp, fp);
+    ldm(ia_w, sp, fp.bit() | lr.bit());
+  }
 }
 
 
 void MacroAssembler::EnterExitFrame(bool save_doubles, int stack_space) {
   // Set up the frame structure on the stack.
   ASSERT_EQ(2 * kPointerSize, ExitFrameConstants::kCallerSPDisplacement);
   ASSERT_EQ(1 * kPointerSize, ExitFrameConstants::kCallerPCOffset);
   ASSERT_EQ(0 * kPointerSize, ExitFrameConstants::kCallerFPOffset);
   Push(lr, fp);
   mov(fp, Operand(sp));  // Set up new frame pointer.
@@ skipping 3126 matching lines @@
 void CodePatcher::EmitCondition(Condition cond) {
   Instr instr = Assembler::instr_at(masm_.pc_);
   instr = (instr & ~kCondMask) | cond;
   masm_.emit(instr);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM