X64: A bunch of small fixes.

Make push/pop use emit_optional_rex32.
Fix bug in disassembler (swapped name of comisd/ucomisd).
Use fstp in FCmp macro.

Review URL: http://codereview.chromium.org/2818026

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4928 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x64/assembler-x64.cc

@@ -376,8 +376,13 @@ void Assembler::GetCode(CodeDesc* desc) {
 
 void Assembler::Align(int m) {
   ASSERT(IsPowerOf2(m));
-  while ((pc_offset() & (m - 1)) != 0) {
-    nop();
+  int delta = (m - (pc_offset() & (m - 1))) & (m - 1);
+  while (delta >= 9) {
+    nop(9);
+    delta -= 9;
+  }
+  if (delta > 0) {
+    nop(delta);
   }
 }
 
@@ -837,9 +842,7 @@ void Assembler::call(Register adr) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   // Opcode: FF /2 r64.
-  if (adr.high_bit()) {
-    emit_rex_64(adr);
-  }
+  emit_optional_rex_32(adr);
   emit(0xFF);
   emit_modrm(0x2, adr);
 }
@@ -849,9 +852,9 @@ void Assembler::call(const Operand& op) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   // Opcode: FF /2 m64.
-  emit_rex_64(op);
+  emit_optional_rex_32(op);
   emit(0xFF);
-  emit_operand(2, op);
+  emit_operand(0x2, op);
 }
 
 
@@ -1270,9 +1273,7 @@ void Assembler::jmp(Register target) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   // Opcode FF/4 r64.
-  if (target.high_bit()) {
-    emit_rex_64(target);
-  }
+  emit_optional_rex_32(target);
   emit(0xFF);
   emit_modrm(0x4, target);
 }
@@ -1831,9 +1832,7 @@ void Assembler::nop(int n) {
 void Assembler::pop(Register dst) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
-  if (dst.high_bit()) {
-    emit_rex_64(dst);
-  }
+  emit_optional_rex_32(dst);
   emit(0x58 | dst.low_bits());
 }
 
@@ -1841,7 +1840,7 @@ void Assembler::pop(Register dst) {
 void Assembler::pop(const Operand& dst) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
-  emit_rex_64(dst);  // Could be omitted in some cases.
+  emit_optional_rex_32(dst);
   emit(0x8F);
   emit_operand(0, dst);
 }
@@ -1857,9 +1856,7 @@ void Assembler::popfq() {
 void Assembler::push(Register src) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
-  if (src.high_bit()) {
-    emit_rex_64(src);
-  }
+  emit_optional_rex_32(src);
   emit(0x50 | src.low_bits());
 }
 
@@ -1867,7 +1864,7 @@ void Assembler::push(Register src) {
 void Assembler::push(const Operand& src) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
-  emit_rex_64(src);  // Could be omitted in some cases.
+  emit_optional_rex_32(src);
   emit(0xFF);
   emit_operand(6, src);
 }

src/x64/assembler-x64.h

@@ -46,23 +46,23 @@ namespace internal {
 
 // Test whether a 64-bit value is in a specific range.
 static inline bool is_uint32(int64_t x) {
-  static const int64_t kUInt32Mask = V8_INT64_C(0xffffffff);
-  return x == (x & kUInt32Mask);
+  static const uint64_t kMaxUInt32 = V8_UINT64_C(0xffffffff);
+  return static_cast<uint64_t>(x) <= kMaxUInt32;
 }
 
 static inline bool is_int32(int64_t x) {
-  static const int64_t kMinIntValue = V8_INT64_C(-0x80000000);
-  return is_uint32(x - kMinIntValue);
+  static const int64_t kMinInt32 = -V8_INT64_C(0x80000000);
+  return is_uint32(x - kMinInt32);
 }
 
 static inline bool uint_is_int32(uint64_t x) {
-  static const uint64_t kMaxIntValue = V8_UINT64_C(0x80000000);
-  return x < kMaxIntValue;
+  static const uint64_t kMaxInt32 = V8_UINT64_C(0x7fffffff);
+  return x <= kMaxInt32;
 }
 
 static inline bool is_uint32(uint64_t x) {
-  static const uint64_t kMaxUIntValue = V8_UINT64_C(0x100000000);
-  return x < kMaxUIntValue;
+  static const uint64_t kMaxUInt32 = V8_UINT64_C(0xffffffff);
+  return x <= kMaxUInt32;
 }
 
 // CPU Registers.

src/x64/disasm-x64.cc

@@ -1028,9 +1028,9 @@ int DisassemblerX64::TwoByteOpcodeInstruction(byte* data) {
         if (opcode == 0x57) {
           mnemonic = "xorpd";
         } else if (opcode == 0x2E) {
-          mnemonic = "comisd";
-        } else if (opcode == 0x2F) {
           mnemonic = "ucomisd";
+        } else if (opcode == 0x2F) {
+          mnemonic = "comisd";
         } else {
           UnimplementedInstruction();
         }

src/x64/macro-assembler-x64.cc

@@ -1678,8 +1678,7 @@ void MacroAssembler::Ret() {
 
 void MacroAssembler::FCmp() {
   fucomip();
-  ffree(0);
-  fincstp();
+  fstp(0);
 }
 
 

src/x64/macro-assembler-x64.h

@@ -546,7 +546,8 @@ class MacroAssembler: public Assembler {
                                Register map,
                                Register instance_type);
 
-  // FCmp is similar to integer cmp, but requires unsigned
+  // FCmp compares and pops the two values on top of the FPU stack.
+  // The flag results are similar to integer cmp, but requires unsigned
   // jcc instructions (je, ja, jae, jb, jbe, je, and jz).
   void FCmp();