MIPS: port ARM: Fix context save/restore for VFP registers.

src/mips/code-stubs-mips.cc

 // Copyright 2011 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 3677 matching lines @@
   // a2: reveiver
   // a3: argc
   //
   // Stack:
   // 4 args slots
   // args
 
   // Save callee saved registers on the stack.
   __ MultiPush(kCalleeSaved | ra.bit());
 
+  if (CpuFeatures::IsSupported(FPU)) {
+    CpuFeatures::Scope scope(FPU);
+    // Save callee-saved FPU registers.
+    __ MultiPushFPU(kCalleeSavedFPU);
+  }
+
   // Load argv in s0 register.
-  __ lw(s0, MemOperand(sp, (kNumCalleeSaved + 1) * kPointerSize +
-                           StandardFrameConstants::kCArgsSlotsSize));
+  int offset_to_argv = (kNumCalleeSaved + 1) * kPointerSize;
+  if (CpuFeatures::IsSupported(FPU)) {
+    offset_to_argv += kNumCalleeSavedFPU * kDoubleSize;
+  }
+
+  __ lw(s0, MemOperand(sp, offset_to_argv +
+      StandardFrameConstants::kCArgsSlotsSize));
 
   // We build an EntryFrame.
   __ li(t3, Operand(-1));  // Push a bad frame pointer to fail if it is used.
   int marker = is_construct ? StackFrame::ENTRY_CONSTRUCT : StackFrame::ENTRY;
   __ li(t2, Operand(Smi::FromInt(marker)));
   __ li(t1, Operand(Smi::FromInt(marker)));
   __ li(t0, Operand(ExternalReference(Isolate::k_c_entry_fp_address,
                                       masm->isolate())));
   __ lw(t0, MemOperand(t0));
   __ Push(t3, t2, t1, t0);
@@ skipping 111 matching lines @@
 
   // Restore the top frame descriptors from the stack.
   __ pop(t1);
   __ li(t0, Operand(ExternalReference(Isolate::k_c_entry_fp_address,
                                       masm->isolate())));
   __ sw(t1, MemOperand(t0));
 
   // Reset the stack to the callee saved registers.
   __ addiu(sp, sp, -EntryFrameConstants::kCallerFPOffset);
 
+  __ MultiPopFPU(kCalleeSavedFPU);

[Yang, 2011/08/31 12:38:44]

Shouldn't this be surrounded by the conditional "if
(CpuFeatures::IsSupported(FPU))"?

At least that's what's been done in r8357 and seems to make sense here as well.

[Paul Lind, 2011/09/01 06:50:27]

Done.

+
   // Restore callee saved registers from the stack.
   __ MultiPop(kCalleeSaved | ra.bit());
   // Return.
   __ Jump(ra);
 }
 
 
 // Uses registers a0 to t0.
 // Expected input (depending on whether args are in registers or on the stack):
 // * object: a0 or at sp + 1 * kPointerSize.
@@ skipping 3026 matching lines @@
   __ mov(result, zero_reg);
   __ Ret();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS