[x64] Introduce BMI instructions.

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index 65b65a36222637a7fba42ec9db03062f2c7f9434..42f083554e3dc4b0d7d423a50ccddb65ed71b7fc 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -2885,28 +2885,6 @@ void MacroAssembler::Pinsrd(XMMRegister dst, const Operand& src, int8_t imm8) {
 }
 
 
-void MacroAssembler::Lzcntl(Register dst, Register src) {
-  // TODO(intel): Add support for LZCNT (BMI1/ABM).

[Benedikt Meurer, 2015/04/08 05:45:41]

Keep these functions, because not all machines will support lzcnt. What I meant
was to extend these functions with a special case for LZCNT, i.e.

if (CpuFeatures::IsSupported(LZCNT)) {
  lzcnt(dst, src);
} else {
  old code;
}

-  Label not_zero_src;
-  bsrl(dst, src);
-  j(not_zero, &not_zero_src, Label::kNear);
-  Set(dst, 63);  // 63^31 == 32
-  bind(&not_zero_src);
-  xorl(dst, Immediate(31));  // for x in [0..31], 31^x == 31 - x
-}
-
-
-void MacroAssembler::Lzcntl(Register dst, const Operand& src) {
-  // TODO(intel): Add support for LZCNT (BMI1/ABM).
-  Label not_zero_src;
-  bsrl(dst, src);
-  j(not_zero, &not_zero_src, Label::kNear);
-  Set(dst, 63);  // 63^31 == 32
-  bind(&not_zero_src);
-  xorl(dst, Immediate(31));  // for x in [0..31], 31^x == 31 - x
-}
-
-
 void MacroAssembler::Pushad() {
   Push(rax);
   Push(rcx);