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1; RUN: llc -o - -verify-machineinstrs %s | FileCheck %s2target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"3target triple = "x86_64-unknown-linux-gnu"4 5@data = external dso_local global [3 x i32], align 46@store = external dso_local global i32, align 47 8; %else1 and %then2 end up lowering to identical blocks. These blocks should be9; merged during tail-merging.10; CHECK-LABEL: merge_identical_blocks11; CHECK: movl $data+412; CHECK-NOT: movl $data+413; CHECK: retq14define void @merge_identical_blocks(i1 %a, i1 %b) {15entry:16 br label %if117 18if1: ; predfs = %entry19 br i1 %a, label %else1, label %if220 21else1: ; preds = %if122 %ptr.else1 = getelementptr inbounds [3 x i32], ptr @data, i64 0, i32 123 br label %phi_join24 25if2: ; preds = %if126 br i1 %b, label %then2, label %else227 28then2: ; preds = %if229 %ptr.then2 = getelementptr inbounds [3 x i32], ptr @data, i64 0, i32 130 br label %phi_join31 32else2: ; preds = %if233 %ptr.else2 = getelementptr inbounds [3 x i32], ptr @data, i64 0, i32 234 br label %phi_join35 36phi_join: ; preds = %else1, %then2, %else237 %val.ptr = phi ptr [ %ptr.else1, %else1 ], [ %ptr.then2, %then2 ], [ %ptr.else2, %else2 ]38 %val = load i32, ptr %val.ptr, align 439 store i32 %val, ptr @store, align 440 ret void41}42