ARM: Make use of d16-d31 when available.

src/arm/deoptimizer-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 963 matching lines @@
   const int kNumberOfRegisters = Register::kNumRegisters;
 
   // Everything but pc, lr and ip which will be saved but not restored.
   RegList restored_regs = kJSCallerSaved | kCalleeSaved | ip.bit();
 
   const int kDoubleRegsSize =
       kDoubleSize * DwVfpRegister::kMaxNumAllocatableRegisters;
 
   if (CpuFeatures::IsSupported(VFP2)) {
     CpuFeatures::Scope scope(VFP2);
-    // Save all VFP registers before messing with them.
-    DwVfpRegister first = DwVfpRegister::FromAllocationIndex(0);
-    DwVfpRegister last =
-        DwVfpRegister::FromAllocationIndex(
-            DwVfpRegister::kMaxNumAllocatableRegisters - 1);
-    ASSERT(last.code() > first.code());
-    ASSERT((last.code() - first.code()) ==
-           (DwVfpRegister::kMaxNumAllocatableRegisters - 1));
-#ifdef DEBUG
-    int max = DwVfpRegister::kMaxNumAllocatableRegisters - 1;
-    for (int i = 0; i <= max; i++) {
-      ASSERT((DwVfpRegister::FromAllocationIndex(i).code() <= last.code()) &&
-             (DwVfpRegister::FromAllocationIndex(i).code() >= first.code()));
-    }
-#endif
-    __ vstm(db_w, sp, first, last);
+    // Save all allocatable VFP registers before messing with them.
+    ASSERT(kDoubleRegZero.code() == 14);
+    ASSERT(kScratchDoubleReg.code() == 15);
+
+    // Check CPU flags for number of registers, setting the Z condition flag.
+    __ CheckFor32DRegs(ip);
+
+    // Push registers d0-d13, and possibly d16-d31, on the stack.
+    __ vstm(db_w, sp, d16, d31, ne);
+    __ sub(sp, sp, Operand(16 * kDoubleSize), LeaveCC, eq);
+    __ vstm(db_w, sp, d0, d13);
   } else {
     __ sub(sp, sp, Operand(kDoubleRegsSize));
   }
 
   // Push all 16 registers (needed to populate FrameDescription::registers_).
   // TODO(1588) Note that using pc with stm is deprecated, so we should perhaps
   // handle this a bit differently.
   __ stm(db_w, sp, restored_regs  | sp.bit() | lr.bit() | pc.bit());
 
   const int kSavedRegistersAreaSize =
@@ skipping 46 matching lines @@
     int offset = (i * kPointerSize) + FrameDescription::registers_offset();
     __ ldr(r2, MemOperand(sp, i * kPointerSize));
     __ str(r2, MemOperand(r1, offset));
   }
 
   if (CpuFeatures::IsSupported(VFP2)) {
     CpuFeatures::Scope scope(VFP2);
     // Copy VFP registers to
     // double_registers_[DoubleRegister::kMaxNumAllocatableRegisters]
     int double_regs_offset = FrameDescription::double_registers_offset();
-    for (int i = 0; i < DwVfpRegister::NumAllocatableRegisters(); ++i) {
+    for (int i = 0; i < DwVfpRegister::kMaxNumAllocatableRegisters; ++i) {
       int dst_offset = i * kDoubleSize + double_regs_offset;
       int src_offset = i * kDoubleSize + kNumberOfRegisters * kPointerSize;
       __ vldr(d0, sp, src_offset);
       __ vstr(d0, r1, dst_offset);
     }
   }
 
   // Remove the bailout id, eventually return address, and the saved registers
   // from the stack.
   if (type() == EAGER || type() == OSR) {
@@ skipping 27 matching lines @@
   // r0: deoptimizer object; r1: scratch.
   __ PrepareCallCFunction(1, r1);
   // Call Deoptimizer::ComputeOutputFrames().
   {
     AllowExternalCallThatCantCauseGC scope(masm());
     __ CallCFunction(
         ExternalReference::compute_output_frames_function(isolate), 1);
   }
   __ pop(r0);  // Restore deoptimizer object (class Deoptimizer).
 
+  // TODO(hans): Change the code below to not clobber r0, so that it can be
+  // used in the "restore the d registers" code further down, making this mov
+  // redundant.
+  __ mov(r4, r0);
+
   // Replace the current (input) frame with the output frames.
   Label outer_push_loop, inner_push_loop,
       outer_loop_header, inner_loop_header;
   // Outer loop state: r0 = current "FrameDescription** output_",
   // r1 = one past the last FrameDescription**.
   __ ldr(r1, MemOperand(r0, Deoptimizer::output_count_offset()));
   __ ldr(r0, MemOperand(r0, Deoptimizer::output_offset()));  // r0 is output_.
   __ add(r1, r0, Operand(r1, LSL, 2));
   __ jmp(&outer_loop_header);
   __ bind(&outer_push_loop);
   // Inner loop state: r2 = current FrameDescription*, r3 = loop index.
   __ ldr(r2, MemOperand(r0, 0));  // output_[ix]
   __ ldr(r3, MemOperand(r2, FrameDescription::frame_size_offset()));
   __ jmp(&inner_loop_header);
   __ bind(&inner_push_loop);
   __ sub(r3, r3, Operand(sizeof(uint32_t)));
   __ add(r6, r2, Operand(r3));
   __ ldr(r7, MemOperand(r6, FrameDescription::frame_content_offset()));
   __ push(r7);
   __ bind(&inner_loop_header);
   __ cmp(r3, Operand::Zero());
   __ b(ne, &inner_push_loop);  // test for gt?
   __ add(r0, r0, Operand(kPointerSize));
   __ bind(&outer_loop_header);
   __ cmp(r0, r1);
   __ b(lt, &outer_push_loop);
 
+  if (CpuFeatures::IsSupported(VFP2)) {
+    CpuFeatures::Scope scope(VFP2);
+    // In case of OSR, we have to restore the d registers.
+    if (type() == OSR) {
+      // Check CPU flags for number of registers, setting the Z condition flag.
+      __ CheckFor32DRegs(ip);
+
+      __ ldr(r1, MemOperand(r4, Deoptimizer::input_offset()));
+      int src_offset = FrameDescription::double_registers_offset();
+      for (int i = 0; i < DwVfpRegister::kNumRegisters; ++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;
+      }
+    }
+  }
+
   // Push state, pc, and continuation from the last output frame.
   if (type() != OSR) {
     __ 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 37 matching lines @@
     __ push(ip);
     __ b(&done);
     ASSERT(masm()->pc_offset() - start == table_entry_size_);
   }
   __ bind(&done);
 }
 
 #undef __
 
 } }  // namespace v8::internal