[arm][stubs] Fix d16-d31 preservation on stub failure

src/arm/deoptimizer-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
 #include "src/register-configuration.h"
 #include "src/safepoint-table.h"
 
@@ skipping 247 matching lines @@
   __ b(ne, &inner_push_loop);  // test for gt?
   __ add(r4, r4, Operand(kPointerSize));
   __ bind(&outer_loop_header);
   __ cmp(r4, r1);
   __ b(lt, &outer_push_loop);
 
   // Check CPU flags for number of registers, setting the Z condition flag.
   __ CheckFor32DRegs(ip);
 
   __ ldr(r1, MemOperand(r0, Deoptimizer::input_offset()));
-  int src_offset = FrameDescription::double_registers_offset();
-  for (int i = 0; i < DwVfpRegister::kMaxNumRegisters; ++i) {
-    if (i == kDoubleRegZero.code()) continue;
-    if (i == kScratchDoubleReg.code()) continue;
-
-    const DwVfpRegister reg = DwVfpRegister::from_code(i);
-    __ vldr(reg, r1, src_offset, i < 16 ? al : ne);
-    src_offset += kDoubleSize;
+  for (int i = 0; i < config->num_allocatable_double_registers(); ++i) {

[Jakob Kummerow, 2016/03/09 11:07:24]

cf. lines 194ff above. Both loops should follow the same logic.

+    int code = config->GetAllocatableDoubleCode(i);
+    DwVfpRegister reg = DwVfpRegister::from_code(code);
+    int src_offset = code * kDoubleSize + double_regs_offset;
+    __ vldr(reg, r1, src_offset);
   }
 
   // Push state, pc, and continuation from the last output frame.
   __ ldr(r6, MemOperand(r2, FrameDescription::state_offset()));
   __ push(r6);
   __ ldr(r6, MemOperand(r2, FrameDescription::pc_offset()));
   __ push(r6);
   __ ldr(r6, MemOperand(r2, FrameDescription::continuation_offset()));
   __ push(r6);
 
@@ skipping 48 matching lines @@
 void FrameDescription::SetCallerConstantPool(unsigned offset, intptr_t value) {
   DCHECK(FLAG_enable_embedded_constant_pool);
   SetFrameSlot(offset, value);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8