forked from OSchip/llvm-project
33 lines
672 B
LLVM
33 lines
672 B
LLVM
; RUN: opt -instcombine %s -S | FileCheck %s
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; Check that code corresponding to the following C function is
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; simplified into a single ASR operation:
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;
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; int test_asr(int a, int b) {
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; return a < 0 ? -(-a - 1 >> b) - 1 : a >> b;
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; }
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;
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define i32 @test_asr(i32 %a, i32 %b) {
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entry:
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%c = icmp slt i32 %a, 0
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br i1 %c, label %bb2, label %bb3
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bb2:
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%t1 = sub i32 0, %a
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%not = sub i32 %t1, 1
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%d = ashr i32 %not, %b
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%t2 = sub i32 0, %d
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%not2 = sub i32 %t2, 1
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br label %bb4
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bb3:
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%e = ashr i32 %a, %b
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br label %bb4
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bb4:
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%f = phi i32 [ %not2, %bb2 ], [ %e, %bb3 ]
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ret i32 %f
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; CHECK: @test_asr
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; CHECK: bb4:
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; CHECK: %f = ashr i32 %a, %b
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; CHECK: ret i32 %f
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}
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