X64: Make smi memory operations work directly on the embedded value.

Adds Operand-relative Operand constructor.

Review URL: http://codereview.chromium.org/2242002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4725 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x64/assembler-x64.cc

@@ -239,6 +239,52 @@ Operand::Operand(Register index,
 }
 
 
+Operand::Operand(const Operand& operand, int32_t offset) {
+  ASSERT(operand.len_ >= 1);
+  // Operand encodes REX ModR/M [SIB] [Disp].
+  byte modrm = operand.buf_[0];
+  ASSERT(modrm < 0xC0);  // Disallow mode 3 (register target).
+  bool has_sib = ((modrm & 0x07) == 0x04);
+  byte mode = modrm & 0xC0;
+  int disp_offset = has_sib ? 2 : 1;
+  int base_reg = (has_sib ? operand.buf_[1] : modrm) & 0x07;
+  // Mode 0 with rbp/r13 as ModR/M or SIB base register always has a 32-bit
+  // displacement.
+  bool is_baseless = (mode == 0) && (base_reg == 0x05);  // No base or RIP base.
+  int32_t disp_value = 0;
+  if (mode == 0x80 || is_baseless) {
+    // Mode 2 or mode 0 with rbp/r13 as base: Word displacement.
+    disp_value = *reinterpret_cast<const int32_t*>(&operand.buf_[disp_offset]);
+  } else if (mode == 0x40) {
+    // Mode 1: Byte displacement.
+    disp_value = static_cast<signed char>(operand.buf_[disp_offset]);
+  }
+
+  // Write new operand with same registers, but with modified displacement.
+  ASSERT(offset >= 0 ? disp_value + offset > disp_value
+                     : disp_value + offset < disp_value);  // No overflow.
+  disp_value += offset;
+  rex_ = operand.rex_;
+  if (!is_int8(disp_value) || is_baseless) {
+    // Need 32 bits of displacement, mode 2 or mode 1 with register rbp/r13.
+    buf_[0] = (modrm & 0x3f) | (is_baseless ? 0x00 : 0x80);
+    len_ = disp_offset + 4;
+    Memory::int32_at(&buf_[disp_offset]) = disp_value;
+  } else if (disp_value != 0 || (base_reg == 0x05)) {
+    // Need 8 bits of displacement.
+    buf_[0] = (modrm & 0x3f) | 0x40;  // Mode 1.
+    len_ = disp_offset + 1;
+    buf_[disp_offset] = static_cast<byte>(disp_value);
+  } else {
+    // Need no displacement.
+    buf_[0] = (modrm & 0x3f);  // Mode 0.
+    len_ = disp_offset;
+  }
+  if (has_sib) {
+    buf_[1] = operand.buf_[1];
+  }
+}
+
 // -----------------------------------------------------------------------------
 // Implementation of Assembler.
 

src/x64/assembler-x64.h

@@ -300,12 +300,16 @@ class Operand BASE_EMBEDDED {
           ScaleFactor scale,
           int32_t disp);
 
+  // Offset from existing memory operand.
+  // Offset is added to existing displacement as 32-bit signed values and
+  // this must not overflow.
+  Operand(const Operand& base, int32_t offset);
+
  private:
   byte rex_;
   byte buf_[10];
   // The number of bytes in buf_.
   unsigned int len_;
-  RelocInfo::Mode rmode_;
 
   // Set the ModR/M byte without an encoded 'reg' register. The
   // register is encoded later as part of the emit_operand operation.

src/x64/macro-assembler-x64.cc

@@ -603,7 +603,7 @@ void MacroAssembler::SmiCompare(Register dst, Smi* src) {
 }
 
 
-void MacroAssembler::SmiCompare(Register  dst, const Operand& src) {
+void MacroAssembler::SmiCompare(Register dst, const Operand& src) {
   cmpq(dst, src);
 }
 
@@ -614,13 +614,7 @@ void MacroAssembler::SmiCompare(const Operand& dst, Register src) {
 
 
 void MacroAssembler::SmiCompare(const Operand& dst, Smi* src) {
-  if (src->value() == 0) {
-    // Only tagged long smi to have 32-bit representation.
-    cmpq(dst, Immediate(0));
-  } else {
-    Move(kScratchRegister, src);
-    cmpq(dst, kScratchRegister);
-  }
+  cmpl(Operand(dst, kIntSize), Immediate(src->value()));
 }
 
 
@@ -922,8 +916,7 @@ void MacroAssembler::SmiAddConstant(Register dst, Register src, Smi* constant) {
 
 void MacroAssembler::SmiAddConstant(const Operand& dst, Smi* constant) {
   if (constant->value() != 0) {
-    Move(kScratchRegister, constant);
-    addq(dst, kScratchRegister);
+    addl(Operand(dst, kIntSize), Immediate(constant->value()));
   }
 }
 
@@ -1607,13 +1600,7 @@ void MacroAssembler::Drop(int stack_elements) {
 
 
 void MacroAssembler::Test(const Operand& src, Smi* source) {
-  intptr_t smi = reinterpret_cast<intptr_t>(source);
-  if (is_int32(smi)) {
-    testl(src, Immediate(static_cast<int32_t>(smi)));
-  } else {
-    Move(kScratchRegister, source);
-    testq(src, kScratchRegister);
-  }
+  testl(Operand(src, kIntSize), Immediate(source->value()));
 }
 
 

test/cctest/test-macro-assembler-x64.cc

@@ -61,6 +61,7 @@ using v8::internal::r12;  // Remember: r12..r15 are callee save!
 using v8::internal::r13;
 using v8::internal::r14;
 using v8::internal::r15;
+using v8::internal::times_pointer_size;
 using v8::internal::FUNCTION_CAST;
 using v8::internal::CodeDesc;
 using v8::internal::less_equal;
@@ -75,6 +76,8 @@ using v8::internal::positive;
 using v8::internal::Smi;
 using v8::internal::kSmiTagMask;
 using v8::internal::kSmiValueSize;
+using v8::internal::kPointerSize;
+using v8::internal::kIntSize;
 
 // Test the x64 assembler by compiling some simple functions into
 // a buffer and executing them.  These tests do not initialize the
@@ -2053,4 +2056,358 @@ TEST(PositiveSmiTimesPowerOfTwoToInteger64) {
 }
 
 
+TEST(OperandOffset) {
+  int data[256];
+  for (int i = 0; i < 256; i++) { data[i] = i * 0x01010101; }
+
+  // Allocate an executable page of memory.
+  size_t actual_size;
+  byte* buffer =
+      static_cast<byte*>(OS::Allocate(Assembler::kMinimalBufferSize * 2,
+                                      &actual_size,
+                                      true));
+  CHECK(buffer);
+  HandleScope handles;
+  MacroAssembler assembler(buffer, static_cast<int>(actual_size));
+
+  MacroAssembler* masm = &assembler;
+  masm->set_allow_stub_calls(false);
+  Label exit;
+
+  __ push(r12);
+  __ push(r13);
+  __ push(rbx);
+  __ push(rbp);
+  __ push(Immediate(0x100));  // <-- rbp
+  __ movq(rbp, rsp);
+  __ push(Immediate(0x101));
+  __ push(Immediate(0x102));
+  __ push(Immediate(0x103));
+  __ push(Immediate(0x104));
+  __ push(Immediate(0x105));  // <-- rbx
+  __ push(Immediate(0x106));
+  __ push(Immediate(0x107));
+  __ push(Immediate(0x108));
+  __ push(Immediate(0x109));  // <-- rsp
+  // rbp = rsp[9]
+  // r12 = rsp[3]
+  // rbx = rsp[5]
+  // r13 = rsp[7]
+  __ lea(r12, Operand(rsp, 3 * kPointerSize));
+  __ lea(r13, Operand(rbp, -3 * kPointerSize));
+  __ lea(rbx, Operand(rbp, -5 * kPointerSize));
+  __ movl(rcx, Immediate(2));
+  __ movq(r8, reinterpret_cast<uintptr_t>(&data[128]), RelocInfo::NONE);
+  __ movl(rax, Immediate(1));
+
+  Operand sp0 = Operand(rsp, 0);
+
+  // Test 1.
+  __ movl(rdx, sp0);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x109));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Test 2.
+  // Zero to non-zero displacement.
+  __ movl(rdx, Operand(sp0, 2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x107));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand sp2 = Operand(rsp, 2 * kPointerSize);
+
+  // Test 3.
+  __ movl(rdx, sp2);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x107));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(sp2, 2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x105));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Non-zero to zero displacement.
+  __ movl(rdx, Operand(sp2, -2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x109));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand sp2c2 = Operand(rsp, rcx, times_pointer_size, 2 * kPointerSize);
+
+  // Test 6.
+  __ movl(rdx, sp2c2);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x105));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(sp2c2, 2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x103));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Non-zero to zero displacement.
+  __ movl(rdx, Operand(sp2c2, -2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x107));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+
+  Operand bp0 = Operand(rbp, 0);
+
+  // Test 9.
+  __ movl(rdx, bp0);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x100));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Zero to non-zero displacement.
+  __ movl(rdx, Operand(bp0, -2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x102));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand bp2 = Operand(rbp, -2 * kPointerSize);
+
+  // Test 11.
+  __ movl(rdx, bp2);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x102));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Non-zero to zero displacement.
+  __ movl(rdx, Operand(bp2, 2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x100));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bp2, -2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x104));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand bp2c4 = Operand(rbp, rcx, times_pointer_size, -4 * kPointerSize);
+
+  // Test 14:
+  __ movl(rdx, bp2c4);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x102));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bp2c4, 2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x100));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bp2c4, -2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x104));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand bx0 = Operand(rbx, 0);
+
+  // Test 17.
+  __ movl(rdx, bx0);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x105));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bx0, 5 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x100));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bx0, -4 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x109));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand bx2 = Operand(rbx, 2 * kPointerSize);
+
+  // Test 20.
+  __ movl(rdx, bx2);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x103));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bx2, 2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x101));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Non-zero to zero displacement.
+  __ movl(rdx, Operand(bx2, -2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x105));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand bx2c2 = Operand(rbx, rcx, times_pointer_size, -2 * kPointerSize);
+
+  // Test 23.
+  __ movl(rdx, bx2c2);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x105));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bx2c2, 2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x103));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(bx2c2, -2 * kPointerSize));
+  __ cmpl(rdx, Immediate(0x107));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand r80 = Operand(r8, 0);
+
+  // Test 26.
+  __ movl(rdx, r80);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x80808080));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, -8 * kIntSize));
+  __ cmpl(rdx, Immediate(0x78787878));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, 8 * kIntSize));
+  __ cmpl(rdx, Immediate(0x88888888));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, -64 * kIntSize));
+  __ cmpl(rdx, Immediate(0x40404040));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, 64 * kIntSize));
+  __ cmpl(rdx, Immediate(0xC0C0C0C0));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  Operand r88 = Operand(r8, 8 * kIntSize);
+
+  // Test 31.
+  __ movl(rdx, r88);  // Sanity check.
+  __ cmpl(rdx, Immediate(0x88888888));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r88, -8 * kIntSize));
+  __ cmpl(rdx, Immediate(0x80808080));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r88, 8 * kIntSize));
+  __ cmpl(rdx, Immediate(0x90909090));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r88, -64 * kIntSize));
+  __ cmpl(rdx, Immediate(0x48484848));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r88, 64 * kIntSize));
+  __ cmpl(rdx, Immediate(0xC8C8C8C8));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+
+  Operand r864 = Operand(r8, 64 * kIntSize);
+
+  // Test 36.
+  __ movl(rdx, r864);  // Sanity check.
+  __ cmpl(rdx, Immediate(0xC0C0C0C0));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r864, -8 * kIntSize));
+  __ cmpl(rdx, Immediate(0xB8B8B8B8));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r864, 8 * kIntSize));
+  __ cmpl(rdx, Immediate(0xC8C8C8C8));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r864, -64 * kIntSize));
+  __ cmpl(rdx, Immediate(0x80808080));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r864, 32 * kIntSize));
+  __ cmpl(rdx, Immediate(0xE0E0E0E0));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // 32-bit offset to 8-bit offset.
+  __ movl(rdx, Operand(r864, -60 * kIntSize));
+  __ cmpl(rdx, Immediate(0x84848484));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r864, 60 * kIntSize));
+  __ cmpl(rdx, Immediate(0xFCFCFCFC));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Test unaligned offsets.
+
+  // Test 43.
+  __ movl(rdx, Operand(r80, 2));
+  __ cmpl(rdx, Immediate(0x81818080));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, -2));
+  __ cmpl(rdx, Immediate(0x80807F7F));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, 126));
+  __ cmpl(rdx, Immediate(0xA0A09F9F));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, -126));
+  __ cmpl(rdx, Immediate(0x61616060));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, 254));
+  __ cmpl(rdx, Immediate(0xC0C0BFBF));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  __ movl(rdx, Operand(r80, -254));
+  __ cmpl(rdx, Immediate(0x41414040));
+  __ j(not_equal, &exit);
+  __ incq(rax);
+
+  // Success.
+
+  __ movl(rax, Immediate(0));
+  __ bind(&exit);
+  __ lea(rsp, Operand(rbp, kPointerSize));
+  __ pop(rbp);
+  __ pop(rbx);
+  __ pop(r13);
+  __ pop(r12);
+  __ ret(0);
+
+
+  CodeDesc desc;
+  masm->GetCode(&desc);
+  // Call the function from C++.
+  int result = FUNCTION_CAST<F0>(buffer)();
+  CHECK_EQ(0, result);
+}
+
+
+
 #undef __