PPC/s390: [deoptimizer, cleanup] Don't store values of single precision fp registers

Port 556e4859

Original Commit Message:

    Instead of storing the values of the single precision floating point registers,
    get their values from the aliased double precision registers.

    This saves, on arm64, 184 bytes per deoptimisation kind function (552 in total)
    and 128 bytes in the RegisterValues class.

R=joey.gouly@arm.com, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: If38a721cfaefb7980902f4f963119cb88061e342
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1726857Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#63006}

src/deoptimizer/ppc/deoptimizer-ppc.cc

@@ -31,7 +31,6 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
   RegList saved_regs = restored_regs | sp.bit();
 
   const int kDoubleRegsSize = kDoubleSize * DoubleRegister::kNumRegisters;
-  const int kFloatRegsSize = kFloatSize * FloatRegister::kNumRegisters;
 
   // Save all double registers before messing with them.
   __ subi(sp, sp, Operand(kDoubleRegsSize));
@@ -42,14 +41,6 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
     int offset = code * kDoubleSize;
     __ stfd(dreg, MemOperand(sp, offset));
   }
-  // Save all float registers before messing with them.
-  __ subi(sp, sp, Operand(kFloatRegsSize));
-  for (int i = 0; i < config->num_allocatable_float_registers(); ++i) {
-    int code = config->GetAllocatableFloatCode(i);
-    const FloatRegister freg = FloatRegister::from_code(code);
-    int offset = code * kFloatSize;
-    __ stfs(freg, MemOperand(sp, offset));
-  }
 
   // Push saved_regs (needed to populate FrameDescription::registers_).
   // Leave gaps for other registers.
@@ -67,7 +58,7 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
     __ StoreP(fp, MemOperand(scratch));
   }
   const int kSavedRegistersAreaSize =
-      (kNumberOfRegisters * kPointerSize) + kDoubleRegsSize + kFloatRegsSize;
+      (kNumberOfRegisters * kPointerSize) + kDoubleRegsSize;
 
   // Get the bailout id is passed as r29 by the caller.
   __ mr(r5, r29);
@@ -117,21 +108,10 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
   for (int i = 0; i < config->num_allocatable_double_registers(); ++i) {
     int code = config->GetAllocatableDoubleCode(i);
     int dst_offset = code * kDoubleSize + double_regs_offset;
-    int src_offset =
-        code * kDoubleSize + kNumberOfRegisters * kPointerSize + kFloatRegsSize;
+    int src_offset = code * kDoubleSize + kNumberOfRegisters * kPointerSize;
     __ lfd(d0, MemOperand(sp, src_offset));
     __ stfd(d0, MemOperand(r4, dst_offset));
   }
-  int float_regs_offset = FrameDescription::float_registers_offset();
-  // Copy float registers to
-  // float_registers_[FloatRegister::kNumRegisters]
-  for (int i = 0; i < config->num_allocatable_float_registers(); ++i) {
-    int code = config->GetAllocatableFloatCode(i);
-    int dst_offset = code * kFloatSize + float_regs_offset;
-    int src_offset = code * kFloatSize + kNumberOfRegisters * kPointerSize;
-    __ lfs(d0, MemOperand(sp, src_offset));
-    __ stfs(d0, MemOperand(r4, dst_offset));
-  }
 
   // Remove the saved registers from the stack.
   __ addi(sp, sp, Operand(kSavedRegistersAreaSize));

src/deoptimizer/s390/deoptimizer-s390.cc

@@ -28,7 +28,6 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
   RegList restored_regs = kJSCallerSaved | kCalleeSaved;
 
   const int kDoubleRegsSize = kDoubleSize * DoubleRegister::kNumRegisters;
-  const int kFloatRegsSize = kFloatSize * FloatRegister::kNumRegisters;
 
   // Save all double registers before messing with them.
   __ lay(sp, MemOperand(sp, -kDoubleRegsSize));
@@ -39,14 +38,6 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
     int offset = code * kDoubleSize;
     __ StoreDouble(dreg, MemOperand(sp, offset));
   }
-  // Save all float registers before messing with them.
-  __ lay(sp, MemOperand(sp, -kFloatRegsSize));
-  for (int i = 0; i < config->num_allocatable_float_registers(); ++i) {
-    int code = config->GetAllocatableFloatCode(i);
-    const FloatRegister dreg = FloatRegister::from_code(code);
-    int offset = code * kFloatSize;
-    __ StoreFloat32(dreg, MemOperand(sp, offset));
-  }
 
   // Push all GPRs onto the stack
   __ lay(sp, MemOperand(sp, -kNumberOfRegisters * kPointerSize));
@@ -57,7 +48,7 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
   __ StoreP(fp, MemOperand(r1));
 
   const int kSavedRegistersAreaSize =
-      (kNumberOfRegisters * kPointerSize) + kDoubleRegsSize + kFloatRegsSize;
+      (kNumberOfRegisters * kPointerSize) + kDoubleRegsSize;
 
   // The bailout id is passed using r10
   __ LoadRR(r4, r10);
@@ -119,25 +110,12 @@ void Deoptimizer::GenerateDeoptimizationEntries(MacroAssembler* masm,
   for (int i = 0; i < config->num_allocatable_double_registers(); ++i) {
     int code = config->GetAllocatableDoubleCode(i);
     int dst_offset = code * kDoubleSize + double_regs_offset;
-    int src_offset =
-        code * kDoubleSize + kNumberOfRegisters * kPointerSize + kFloatRegsSize;
+    int src_offset = code * kDoubleSize + kNumberOfRegisters * kPointerSize;
     // TODO(joransiu): MVC opportunity
     __ LoadDouble(d0, MemOperand(sp, src_offset));
     __ StoreDouble(d0, MemOperand(r3, dst_offset));
   }
 
-  int float_regs_offset = FrameDescription::float_registers_offset();
-  // Copy float registers to
-  // float_registers_[FloatRegister::kNumRegisters]
-  for (int i = 0; i < config->num_allocatable_float_registers(); ++i) {
-    int code = config->GetAllocatableFloatCode(i);
-    int dst_offset = code * kFloatSize + float_regs_offset;
-    int src_offset = code * kFloatSize + kNumberOfRegisters * kPointerSize;
-    // TODO(joransiu): MVC opportunity
-    __ LoadFloat32(d0, MemOperand(sp, src_offset));
-    __ StoreFloat32(d0, MemOperand(r3, dst_offset));
-  }
-
   // Remove the saved registers from the stack.
   __ la(sp, MemOperand(sp, kSavedRegistersAreaSize));