forked from OSchip/llvm-project
42 lines
1.5 KiB
LLVM
42 lines
1.5 KiB
LLVM
; RUN: llc -o - -verify-machineinstrs %s | FileCheck %s
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target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
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target triple = "x86_64-unknown-linux-gnu"
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@data = external dso_local global [3 x i32], align 4
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@store = external dso_local global i32, align 4
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; %else1 and %then2 end up lowering to identical blocks. These blocks should be
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; merged during tail-merging.
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; CHECK-LABEL: merge_identical_blocks
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; CHECK: movl $data+4
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; CHECK-NOT: movl $data+4
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; CHECK: retq
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define void @merge_identical_blocks(i1 %a, i1 %b) {
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entry:
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br label %if1
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if1: ; predfs = %entry
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br i1 %a, label %else1, label %if2
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else1: ; preds = %if1
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%ptr.else1 = getelementptr inbounds [3 x i32], [3 x i32]* @data, i64 0, i32 1
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br label %phi_join
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if2: ; preds = %if1
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br i1 %b, label %then2, label %else2
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then2: ; preds = %if2
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%ptr.then2 = getelementptr inbounds [3 x i32], [3 x i32]* @data, i64 0, i32 1
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br label %phi_join
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else2: ; preds = %if2
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%ptr.else2 = getelementptr inbounds [3 x i32], [3 x i32]* @data, i64 0, i32 2
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br label %phi_join
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phi_join: ; preds = %else1, %then2, %else2
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%val.ptr = phi i32* [ %ptr.else1, %else1 ], [ %ptr.then2, %then2 ], [ %ptr.else2, %else2 ]
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%val = load i32, i32* %val.ptr, align 4
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store i32 %val, i32* @store, align 4
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ret void
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}
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