64 lines
1.4 KiB
LLVM
64 lines
1.4 KiB
LLVM
; RUN: opt -indvars -instcombine -S < %s | FileCheck %s
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;; Test that loop's exit value is rewritten to its initial
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;; value from loop preheader
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define i32 @test1(i32* %var) {
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; CHECK-LABEL: @test1
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entry:
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%cond = icmp eq i32* %var, null
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br label %header
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header:
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%phi_indvar = phi i32 [0, %entry], [%indvar, %loop]
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br i1 %cond, label %loop, label %exit
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loop:
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%indvar = add i32 %phi_indvar, 1
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br label %header
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exit:
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; CHECK: ret i32 0
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ret i32 %phi_indvar
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}
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;; Test that we can not rewrite loop exit value if it's not
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;; a phi node (%indvar is an add instruction in this test).
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define i32 @test2(i32* %var) {
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; CHECK-LABEL: @test2
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entry:
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%cond = icmp eq i32* %var, null
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br label %header
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header:
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%phi_indvar = phi i32 [0, %entry], [%indvar, %header]
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%indvar = add i32 %phi_indvar, 1
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br i1 %cond, label %header, label %exit
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exit:
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; CHECK: ret i32 %indvar
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ret i32 %indvar
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}
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;; Test that we can not rewrite loop exit value if the condition
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;; is not in loop header.
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define i32 @test3(i32* %var) {
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; CHECK-LABEL: @test3
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entry:
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%cond1 = icmp eq i32* %var, null
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br label %header
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header:
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%phi_indvar = phi i32 [0, %entry], [%indvar, %header], [%indvar, %body]
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%indvar = add i32 %phi_indvar, 1
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%cond2 = icmp eq i32 %indvar, 10
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br i1 %cond2, label %header, label %body
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body:
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br i1 %cond1, label %header, label %exit
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exit:
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; CHECK: ret i32 %phi_indvar
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ret i32 %phi_indvar
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}
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