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[X86] Don't mark movabsq as cheap-as-move - it isn't that cheap.

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A simple register copy on X86 is just 3 bytes, whereas movabsq is a 10 byte
instruction. Marking movabsq as not beeing cheap will allow LICM to move it
out of the loop and it also prevents unnecessary rematerializations if the
value is needed in more than one register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201377 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Juergen Ributzka 2014-02-14 00:51:13 +00:00
parent f222ebe86c
commit 5cb9925acd
1 changed files with 5 additions and 3 deletions
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8
lib/Target/X86/X86InstrInfo.td
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@ -1203,13 +1203,15 @@ def MOV16ri : Ii16<0xB8, AddRegFrm, (outs GR16:$dst), (ins i16imm:$src),
def MOV32ri : Ii32<0xB8, AddRegFrm, (outs GR32:$dst), (ins i32imm:$src),
"mov{l}\t{$src, $dst|$dst, $src}",
[(set GR32:$dst, imm:$src)], IIC_MOV>, OpSize32;
def MOV64ri : RIi64<0xB8, AddRegFrm, (outs GR64:$dst), (ins i64imm:$src),
"movabs{q}\t{$src, $dst|$dst, $src}",
[(set GR64:$dst, imm:$src)], IIC_MOV>;
def MOV64ri32 : RIi32S<0xC7, MRM0r, (outs GR64:$dst), (ins i64i32imm:$src),
"mov{q}\t{$src, $dst|$dst, $src}",
[(set GR64:$dst, i64immSExt32:$src)], IIC_MOV>;
}
let isReMaterializable = 1 in {
def MOV64ri : RIi64<0xB8, AddRegFrm, (outs GR64:$dst), (ins i64imm:$src),
"movabs{q}\t{$src, $dst|$dst, $src}",
[(set GR64:$dst, imm:$src)], IIC_MOV>;
}
} // SchedRW
let SchedRW = [WriteStore] in {