X64: Added register holding Smi::FromInt(1).

src/x64/macro-assembler-x64.cc

 // Copyright 2009 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 449 matching lines @@
     cmpq(target, Operand(rsp, 0));
     Assert(equal, "Builtin code object changed");
     pop(target);
   }
   lea(target, FieldOperand(target, Code::kHeaderSize));
 }
 
 
 void MacroAssembler::Set(Register dst, int64_t x) {
   if (x == 0) {
-    xor_(dst, dst);
+    xorl(dst, dst);
   } else if (is_int32(x)) {
     movq(dst, Immediate(static_cast<int32_t>(x)));
   } else if (is_uint32(x)) {
     movl(dst, Immediate(static_cast<uint32_t>(x)));
   } else {
     movq(dst, x, RelocInfo::NONE);
   }
 }
 
-
 void MacroAssembler::Set(const Operand& dst, int64_t x) {
   if (is_int32(x)) {
     movq(dst, Immediate(static_cast<int32_t>(x)));
   } else {
     movq(kScratchRegister, x, RelocInfo::NONE);
     movq(dst, kScratchRegister);
   }
 }
 
 // ----------------------------------------------------------------------------
 // Smi tagging, untagging and tag detection.
 
 static int kSmiShift = kSmiTagSize + kSmiShiftSize;
 
+Register MacroAssembler::GetSmiConstant(Smi* source) {
+  int value = source->value();
+  if (value == 0) {
+    xorl(kScratchRegister, kScratchRegister);
+    return kScratchRegister;
+  }
+  if (value == 1) {
+    return kSmiConstantRegister;
+  }
+  LoadSmiConstant(kScratchRegister, source);
+  return kScratchRegister;
+}
+
+void MacroAssembler::LoadSmiConstant(Register dst, Smi* source) {
+  if (FLAG_debug_code) {
+    movq(dst,
+         reinterpret_cast<uint64_t>(Smi::FromInt(kSmiConstantRegisterValue)),
+         RelocInfo::NONE);
+    cmpq(dst, kSmiConstantRegister);
+    if (allow_stub_calls()) {
+      Assert(equal, "Uninitialized kSmiConstantRegister");
+    } else {
+      Label ok;
+      j(equal, &ok);
+      int3();
+      bind(&ok);
+    }
+  }
+  if (source->value() == 0) {
+    xorl(dst, dst);
+    return;
+  }
+  int value = source->value();
+  bool negative = value < 0;
+  unsigned int uvalue = negative ? -value : value;
+
+  switch (uvalue) {
+    case 9:
+      lea(dst, Operand(kSmiConstantRegister, kSmiConstantRegister, times_8, 0));
+      break;
+    case 8:
+      xorl(dst, dst);
+      lea(dst, Operand(dst, kSmiConstantRegister, times_8, 0));
+      break;
+    case 4:
+      xorl(dst, dst);
+      lea(dst, Operand(dst, kSmiConstantRegister, times_4, 0));
+      break;
+    case 5:
+      lea(dst, Operand(kSmiConstantRegister, kSmiConstantRegister, times_4, 0));
+      break;
+    case 3:
+      lea(dst, Operand(kSmiConstantRegister, kSmiConstantRegister, times_2, 0));
+      break;
+    case 2:
+      lea(dst, Operand(kSmiConstantRegister, kSmiConstantRegister, times_1, 0));
+      break;
+    case 1:
+      movq(dst, kSmiConstantRegister);
+      break;
+    case 0:
+      UNREACHABLE();
+      return;
+    default:
+      movq(dst, reinterpret_cast<uint64_t>(source), RelocInfo::NONE);
+      return;
+  }
+  if (negative) {
+    neg(dst);
+  }
+}
+
 void MacroAssembler::Integer32ToSmi(Register dst, Register src) {
   ASSERT_EQ(0, kSmiTag);
   if (!dst.is(src)) {
     movl(dst, src);
   }
   shl(dst, Immediate(kSmiShift));
 }
 
 
 void MacroAssembler::Integer32ToSmi(Register dst,
@@ skipping 140 matching lines @@
 
 Condition MacroAssembler::CheckSmi(Register src) {
   ASSERT_EQ(0, kSmiTag);
   testb(src, Immediate(kSmiTagMask));
   return zero;
 }
 
 
 Condition MacroAssembler::CheckPositiveSmi(Register src) {
   ASSERT_EQ(0, kSmiTag);
+  // Make mask 0x8000000000000001 and test that both bits are zero.
   movq(kScratchRegister, src);
   rol(kScratchRegister, Immediate(1));
-  testl(kScratchRegister, Immediate(0x03));
+  testb(kScratchRegister, Immediate(3));
   return zero;
 }
 
 
 Condition MacroAssembler::CheckBothSmi(Register first, Register second) {
   if (first.is(second)) {
     return CheckSmi(first);
   }
   ASSERT(kSmiTag == 0 && kHeapObjectTag == 1 && kHeapObjectTagMask == 3);
   leal(kScratchRegister, Operand(first, second, times_1, 0));
   testb(kScratchRegister, Immediate(0x03));
   return zero;
 }
 
 
 Condition MacroAssembler::CheckBothPositiveSmi(Register first,
                                                Register second) {
   if (first.is(second)) {
     return CheckPositiveSmi(first);
   }
   movq(kScratchRegister, first);
   or_(kScratchRegister, second);
   rol(kScratchRegister, Immediate(1));
   testl(kScratchRegister, Immediate(0x03));
   return zero;
 }
 
 
-
 Condition MacroAssembler::CheckEitherSmi(Register first, Register second) {
   if (first.is(second)) {
     return CheckSmi(first);
   }
   movl(kScratchRegister, first);
   andl(kScratchRegister, second);
   testb(kScratchRegister, Immediate(kSmiTagMask));
   return zero;
 }
 
 
 Condition MacroAssembler::CheckIsMinSmi(Register src) {
-  ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
-  movq(kScratchRegister, src);
-  rol(kScratchRegister, Immediate(1));
-  cmpq(kScratchRegister, Immediate(1));
-  return equal;
+  ASSERT(!src.is(kScratchRegister));
+  // If we overflow by subtracting one, it's the minimal smi value.
+  cmpq(src, kSmiConstantRegister);
+  return overflow;
 }
 
 
 Condition MacroAssembler::CheckInteger32ValidSmiValue(Register src) {
   // A 32-bit integer value can always be converted to a smi.
   return always;
 }
 
 
 Condition MacroAssembler::CheckUInteger32ValidSmiValue(Register src) {
   // An unsigned 32-bit integer value is valid as long as the high bit
   // is not set.
-  testq(src, Immediate(0x80000000));
-  return zero;
+  testl(src, src);
+  return positive;
 }
 
 
 void MacroAssembler::SmiNeg(Register dst, Register src, Label* on_smi_result) {
   if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
     movq(kScratchRegister, src);
     neg(dst);  // Low 32 bits are retained as zero by negation.
     // Test if result is zero or Smi::kMinValue.
     cmpq(dst, kScratchRegister);
@@ skipping 72 matching lines @@
     // No overflow checking. Use only when it's known that
     // overflowing is impossible (e.g., subtracting two positive smis).
     if (dst.is(src1)) {
       subq(dst, src2);
     } else {
       movq(dst, src1);
       subq(dst, src2);
     }
     Assert(no_overflow, "Smi subtraction overflow");
   } else if (dst.is(src1)) {
-    movq(kScratchRegister, src1);
-    subq(kScratchRegister, src2);
+    movq(kScratchRegister, src2);
+    cmpq(src1, kScratchRegister);
     j(overflow, on_not_smi_result);
-    movq(src1, kScratchRegister);
+    subq(src1, kScratchRegister);
   } else {
     movq(dst, src1);
     subq(dst, src2);
     j(overflow, on_not_smi_result);
   }
 }
 
 void MacroAssembler::SmiMul(Register dst,
                             Register src1,
                             Register src2,
@@ skipping 52 matching lines @@
                                        Smi* constant,
                                        Label* on_not_smi_result) {
   // Does not assume that src is a smi.
   ASSERT_EQ(static_cast<int>(1), static_cast<int>(kSmiTagMask));
   ASSERT_EQ(0, kSmiTag);
   ASSERT(!dst.is(kScratchRegister));
   ASSERT(!src.is(kScratchRegister));
 
   JumpIfNotSmi(src, on_not_smi_result);
   Register tmp = (dst.is(src) ? kScratchRegister : dst);
-  Move(tmp, constant);
+  LoadSmiConstant(tmp, constant);
   addq(tmp, src);
   j(overflow, on_not_smi_result);
   if (dst.is(src)) {
     movq(dst, tmp);
   }
 }
 
 
 void MacroAssembler::SmiAddConstant(Register dst, Register src, Smi* constant) {
   if (constant->value() == 0) {
     if (!dst.is(src)) {
       movq(dst, src);
     }
+    return;
   } else if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
-
-    Move(kScratchRegister, constant);
-    addq(dst, kScratchRegister);
+    switch (constant->value()) {
+      case 1:
+        addq(dst, kSmiConstantRegister);
+        return;
+      case 2:
+        lea(dst, Operand(src, kSmiConstantRegister, times_2, 0));
+        return;
+      case 4:
+        lea(dst, Operand(src, kSmiConstantRegister, times_4, 0));
+        return;
+      case 8:
+        lea(dst, Operand(src, kSmiConstantRegister, times_8, 0));
+        return;
+      default:
+        Register constant_reg = GetSmiConstant(constant);
+        addq(dst, constant_reg);
+        return;
+    }
   } else {
-    Move(dst, constant);
-    addq(dst, src);
+    switch (constant->value()) {
+      case 1:
+        lea(dst, Operand(src, kSmiConstantRegister, times_1, 0));
+        return;
+      case 2:
+        lea(dst, Operand(src, kSmiConstantRegister, times_2, 0));
+        return;
+      case 4:
+        lea(dst, Operand(src, kSmiConstantRegister, times_4, 0));
+        return;
+      case 8:
+        lea(dst, Operand(src, kSmiConstantRegister, times_8, 0));
+        return;
+      default:
+        LoadSmiConstant(dst, constant);
+        addq(dst, src);
+        return;
+    }
   }
 }
 
 
 void MacroAssembler::SmiAddConstant(const Operand& dst, Smi* constant) {
   if (constant->value() != 0) {
     addl(Operand(dst, kSmiShift / kBitsPerByte), Immediate(constant->value()));
   }
 }
 
 
 void MacroAssembler::SmiAddConstant(Register dst,
                                     Register src,
                                     Smi* constant,
                                     Label* on_not_smi_result) {
   if (constant->value() == 0) {
     if (!dst.is(src)) {
       movq(dst, src);
     }
   } else if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
 
-    Move(kScratchRegister, constant);
-    addq(kScratchRegister, dst);
+    LoadSmiConstant(kScratchRegister, constant);
+    addq(kScratchRegister, src);
     j(overflow, on_not_smi_result);
     movq(dst, kScratchRegister);
   } else {
-    Move(dst, constant);
+    LoadSmiConstant(dst, constant);
     addq(dst, src);
     j(overflow, on_not_smi_result);
   }
 }
 
 
 void MacroAssembler::SmiSubConstant(Register dst, Register src, Smi* constant) {
   if (constant->value() == 0) {
     if (!dst.is(src)) {
       movq(dst, src);
     }
   } else if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
-
-    Move(kScratchRegister, constant);
-    subq(dst, kScratchRegister);
+    Register constant_reg = GetSmiConstant(constant);
+    subq(dst, constant_reg);
   } else {
-    // Subtract by adding the negative, to do it in two operations.
     if (constant->value() == Smi::kMinValue) {
-      Move(dst, constant);
+      LoadSmiConstant(dst, constant);
       // Adding and subtracting the min-value gives the same result, it only
       // differs on the overflow bit, which we don't check here.
       addq(dst, src);
     } else {
       // Subtract by adding the negation.
-      Move(dst, Smi::FromInt(-constant->value()));
+      LoadSmiConstant(dst, Smi::FromInt(-constant->value()));
       addq(dst, src);
     }
   }
 }
 
 
 void MacroAssembler::SmiSubConstant(Register dst,
                                     Register src,
                                     Smi* constant,
                                     Label* on_not_smi_result) {
   if (constant->value() == 0) {
     if (!dst.is(src)) {
       movq(dst, src);
     }
   } else if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
     if (constant->value() == Smi::kMinValue) {
       // Subtracting min-value from any non-negative value will overflow.
       // We test the non-negativeness before doing the subtraction.
       testq(src, src);
       j(not_sign, on_not_smi_result);
-      Move(kScratchRegister, constant);
+      LoadSmiConstant(kScratchRegister, constant);
       subq(dst, kScratchRegister);
     } else {
       // Subtract by adding the negation.
-      Move(kScratchRegister, Smi::FromInt(-constant->value()));
+      LoadSmiConstant(kScratchRegister, Smi::FromInt(-constant->value()));
       addq(kScratchRegister, dst);
       j(overflow, on_not_smi_result);
       movq(dst, kScratchRegister);
     }
   } else {
     if (constant->value() == Smi::kMinValue) {
       // Subtracting min-value from any non-negative value will overflow.
       // We test the non-negativeness before doing the subtraction.
       testq(src, src);
       j(not_sign, on_not_smi_result);
-      Move(dst, constant);
+      LoadSmiConstant(dst, constant);
       // Adding and subtracting the min-value gives the same result, it only
       // differs on the overflow bit, which we don't check here.
       addq(dst, src);
     } else {
       // Subtract by adding the negation.
-      Move(dst, Smi::FromInt(-(constant->value())));
+      LoadSmiConstant(dst, Smi::FromInt(-(constant->value())));
       addq(dst, src);
       j(overflow, on_not_smi_result);
     }
   }
 }
 
 
 void MacroAssembler::SmiDiv(Register dst,
                             Register src1,
                             Register src2,
@@ skipping 133 matching lines @@
   }
   and_(dst, src2);
 }
 
 
 void MacroAssembler::SmiAndConstant(Register dst, Register src, Smi* constant) {
   if (constant->value() == 0) {
     xor_(dst, dst);
   } else if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
-    Move(kScratchRegister, constant);
-    and_(dst, kScratchRegister);
+    Register constant_reg = GetSmiConstant(constant);
+    and_(dst, constant_reg);
   } else {
-    Move(dst, constant);
+    LoadSmiConstant(dst, constant);
     and_(dst, src);
   }
 }
 
 
 void MacroAssembler::SmiOr(Register dst, Register src1, Register src2) {
   if (!dst.is(src1)) {
     movq(dst, src1);
   }
   or_(dst, src2);
 }
 
 
 void MacroAssembler::SmiOrConstant(Register dst, Register src, Smi* constant) {
   if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
-    Move(kScratchRegister, constant);
-    or_(dst, kScratchRegister);
+    Register constant_reg = GetSmiConstant(constant);
+    or_(dst, constant_reg);
   } else {
-    Move(dst, constant);
+    LoadSmiConstant(dst, constant);
     or_(dst, src);
   }
 }
 
 
 void MacroAssembler::SmiXor(Register dst, Register src1, Register src2) {
   if (!dst.is(src1)) {
     movq(dst, src1);
   }
   xor_(dst, src2);
 }
 
 
 void MacroAssembler::SmiXorConstant(Register dst, Register src, Smi* constant) {
   if (dst.is(src)) {
     ASSERT(!dst.is(kScratchRegister));
-    Move(kScratchRegister, constant);
-    xor_(dst, kScratchRegister);
+    Register constant_reg = GetSmiConstant(constant);
+    xor_(dst, constant_reg);
   } else {
-    Move(dst, constant);
+    LoadSmiConstant(dst, constant);
     xor_(dst, src);
   }
 }
 
 
 void MacroAssembler::SmiShiftArithmeticRightConstant(Register dst,
                                                      Register src,
                                                      int shift_value) {
   ASSERT(is_uint5(shift_value));
   if (shift_value > 0) {
@@ skipping 147 matching lines @@
   subq(kScratchRegister, Immediate(1));
   // If src1 is a smi, then scratch register all 1s, else it is all 0s.
   movq(dst, src1);
   xor_(dst, src2);
   and_(dst, kScratchRegister);
   // If src1 is a smi, dst holds src1 ^ src2, else it is zero.
   xor_(dst, src1);
   // If src1 is a smi, dst is src2, else it is src1, i.e., the non-smi.
 }
 
+
 SmiIndex MacroAssembler::SmiToIndex(Register dst,
                                     Register src,
                                     int shift) {
   ASSERT(is_uint6(shift));
   // There is a possible optimization if shift is in the range 60-63, but that
   // will (and must) never happen.
   if (!dst.is(src)) {
     movq(dst, src);
   }
   if (shift < kSmiShift) {
@@ skipping 205 matching lines @@
     push(kScratchRegister);
   }
 }
 
 
 void MacroAssembler::Push(Smi* source) {
   intptr_t smi = reinterpret_cast<intptr_t>(source);
   if (is_int32(smi)) {
     push(Immediate(static_cast<int32_t>(smi)));
   } else {
-    Set(kScratchRegister, smi);
-    push(kScratchRegister);
+    Register constant = GetSmiConstant(source);
+    push(constant);
   }
 }
 
 
 void MacroAssembler::Drop(int stack_elements) {
   if (stack_elements > 0) {
     addq(rsp, Immediate(stack_elements * kPointerSize));
   }
 }
 
@@ skipping 519 matching lines @@
   // Save the frame pointer and the context in top.
   ExternalReference c_entry_fp_address(Top::k_c_entry_fp_address);
   ExternalReference context_address(Top::k_context_address);
   movq(r14, rax);  // Backup rax before we use it.
 
   movq(rax, rbp);
   store_rax(c_entry_fp_address);
   movq(rax, rsi);
   store_rax(context_address);
 
-  // Setup argv in callee-saved register r15. It is reused in LeaveExitFrame,
+  // Setup argv in callee-saved register r12. It is reused in LeaveExitFrame,
   // so it must be retained across the C-call.
   int offset = StandardFrameConstants::kCallerSPOffset - kPointerSize;
-  lea(r15, Operand(rbp, r14, times_pointer_size, offset));
+  lea(r12, Operand(rbp, r14, times_pointer_size, offset));
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
   // Save the state of all registers to the stack from the memory
   // location. This is needed to allow nested break points.
   if (mode == ExitFrame::MODE_DEBUG) {
     // TODO(1243899): This should be symmetric to
     // CopyRegistersFromStackToMemory() but it isn't! esp is assumed
     // correct here, but computed for the other call. Very error
     // prone! FIX THIS.  Actually there are deeper problems with
     // register saving than this asymmetry (see the bug report
@@ skipping 25 matching lines @@
     and_(rsp, kScratchRegister);
   }
 
   // Patch the saved entry sp.
   movq(Operand(rbp, ExitFrameConstants::kSPOffset), rsp);
 }
 
 
 void MacroAssembler::LeaveExitFrame(ExitFrame::Mode mode, int result_size) {
   // Registers:
-  // r15 : argv
+  // r12 : argv
 #ifdef ENABLE_DEBUGGER_SUPPORT
   // Restore the memory copy of the registers by digging them out from
   // the stack. This is needed to allow nested break points.
   if (mode == ExitFrame::MODE_DEBUG) {
     // It's okay to clobber register rbx below because we don't need
     // the function pointer after this.
     const int kCallerSavedSize = kNumJSCallerSaved * kPointerSize;
     int kOffset = ExitFrameConstants::kCodeOffset - kCallerSavedSize;
     lea(rbx, Operand(rbp, kOffset));
     CopyRegistersFromStackToMemory(rbx, rcx, kJSCallerSaved);
   }
 #endif
 
   // Get the return address from the stack and restore the frame pointer.
   movq(rcx, Operand(rbp, 1 * kPointerSize));
   movq(rbp, Operand(rbp, 0 * kPointerSize));
 
   // Pop everything up to and including the arguments and the receiver
   // from the caller stack.
-  lea(rsp, Operand(r15, 1 * kPointerSize));
+  lea(rsp, Operand(r12, 1 * kPointerSize));
 
   // Restore current context from top and clear it in debug mode.
   ExternalReference context_address(Top::k_context_address);
   movq(kScratchRegister, context_address);
   movq(rsi, Operand(kScratchRegister, 0));
 #ifdef DEBUG
   movq(Operand(kScratchRegister, 0), Immediate(0));
 #endif
 
   // Push the return address to get ready to return.
@@ skipping 563 matching lines @@
   CPU::FlushICache(address_, size_);
 
   // Check that the code was patched as expected.
   ASSERT(masm_.pc_ == address_ + size_);
   ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64