Summary:
Created a pattern to match 64-bit mode (and (xor x, -1), y)
to a shorter sequence of instructions.
Before the change, the canonical form is translated to:
xihf %r3, 4294967295
xilf %r3, 4294967295
ngr %r2, %r3
After the change, the canonical form is translated to:
ngr %r3, %r2
xgr %r2, %r3
Reviewers: zhanjunl, uweigand
Subscribers: llvm-commits
Author: assem
Committing on behalf of Assem.
Differential Revision: http://reviews.llvm.org/D21693
llvm-svn: 273887
15 lines
312 B
LLVM
15 lines
312 B
LLVM
; Testing peephole for generating shorter code for (and (xor b, -1), a)
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;
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; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
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define i64 @f1(i64 %a, i64 %b) {
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; CHECK-LABEL: f1:
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; CHECK: ngr %r3, %r2
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; CHECK: xgr %r2, %r3
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; CHECK: br %r14
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%neg = xor i64 %b, -1
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%and = and i64 %neg, %a
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ret i64 %and
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}
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