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-rw-r--r--lib/Target/X86/X86InstrInfo.td3
-rw-r--r--test/CodeGen/X86/xor_not.ll2
2 files changed, 4 insertions, 1 deletions
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 73aa15a81d..fbe03299e0 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -1235,12 +1235,15 @@ let isTwoAddress = 0 in {
}
} // Defs = [EFLAGS]
+// 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 :$dst), (ins GR8 :$src), "not{b}\t$dst",
[(set GR8:$dst, (not GR8:$src))]>;
def NOT16r : I<0xF7, MRM2r, (outs GR16:$dst), (ins GR16:$src), "not{w}\t$dst",
[(set GR16:$dst, (not GR16:$src))]>, OpSize;
def NOT32r : I<0xF7, MRM2r, (outs GR32:$dst), (ins GR32:$src), "not{l}\t$dst",
[(set GR32:$dst, (not GR32:$src))]>;
+}
let isTwoAddress = 0 in {
def NOT8m : I<0xF6, MRM2m, (outs), (ins i8mem :$dst), "not{b}\t$dst",
[(store (not (loadi8 addr:$dst)), addr:$dst)]>;
diff --git a/test/CodeGen/X86/xor_not.ll b/test/CodeGen/X86/xor_not.ll
index 1e89ca8e05..0b1abdf415 100644
--- a/test/CodeGen/X86/xor_not.ll
+++ b/test/CodeGen/X86/xor_not.ll
@@ -1,4 +1,4 @@
-; RUN: llvm-as < %s | llc -march=x86 | grep {not\[lwb\]} | count 3
+; RUN: llvm-as < %s | llc -march=x86 | grep {not\[lwb\]} | count 4
; RUN: llvm-as < %s | llc -march=x86-64 | grep {not\[lwb\]} | count 4
define i32 @test(i32 %a, i32 %b) nounwind {
entry: