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[X86] Remove AddedComplexity from register form of NOT. NFCI 

I believe isProfitableToFold will stop the load folding that this was intended to overcome.

Given an (xor load, -1), isProfitableToFold will see that the immediate can be folded with the xor using a one byte immediate since it can be sign extended. It doesn't know about NOT, but the one byte immediate check is enough to stop the fold.

llvm-svn: 336712
This commit is contained in:
Craig Topper 2018-07-10 19:09:00 +00:00
parent 0f6275ab43
commit 04ded1ac1f
1 changed files with 0 additions and 3 deletions
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3
llvm/lib/Target/X86/X86InstrArithmetic.td
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@ -391,8 +391,6 @@ def NEG64m : RI<0xF7, MRM3m, (outs), (ins i64mem:$dst), "neg{q}\t$dst",
// Note: NOT does not set EFLAGS! // Note: NOT does not set EFLAGS!
let Constraints = "$src1 = $dst", SchedRW = [WriteALU] in { let Constraints = "$src1 = $dst", SchedRW = [WriteALU] in {
// Match xor -1 to not. Favors these over a move imm + xor to save code size.
let AddedComplexity = 15 in {
def NOT8r : I<0xF6, MRM2r, (outs GR8 :$dst), (ins GR8 :$src1), def NOT8r : I<0xF6, MRM2r, (outs GR8 :$dst), (ins GR8 :$src1),
"not{b}\t$dst", "not{b}\t$dst",
[(set GR8:$dst, (not GR8:$src1))]>; [(set GR8:$dst, (not GR8:$src1))]>;
@ -404,7 +402,6 @@ def NOT32r : I<0xF7, MRM2r, (outs GR32:$dst), (ins GR32:$src1),
[(set GR32:$dst, (not GR32:$src1))]>, OpSize32; [(set GR32:$dst, (not GR32:$src1))]>, OpSize32;
def NOT64r : RI<0xF7, MRM2r, (outs GR64:$dst), (ins GR64:$src1), "not{q}\t$dst", def NOT64r : RI<0xF7, MRM2r, (outs GR64:$dst), (ins GR64:$src1), "not{q}\t$dst",
[(set GR64:$dst, (not GR64:$src1))]>; [(set GR64:$dst, (not GR64:$src1))]>;
}
} // Constraints = "$src1 = $dst", SchedRW } // Constraints = "$src1 = $dst", SchedRW
let SchedRW = [WriteALURMW] in { let SchedRW = [WriteALURMW] in {