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; RUN: opt -basicaa -load-combine -instcombine -S < %s | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
declare void @llvm.assume(i1) nounwind
; 'load' before the 'call' gets optimized:
define i64 @test1(i32* nocapture readonly %a, i1 %b) {
; CHECK-LABEL: @test1
; CHECK-DAG: load i64* %1, align 4
; CHECK-DAG: tail call void @llvm.assume(i1 %b)
; CHECK: ret i64
%load1 = load i32* %a, align 4
%conv = zext i32 %load1 to i64
%arrayidx1 = getelementptr inbounds i32* %a, i64 1
%load2 = load i32* %arrayidx1, align 4
tail call void @llvm.assume(i1 %b)
%conv2 = zext i32 %load2 to i64
%shl = shl nuw i64 %conv2, 32
%add = or i64 %shl, %conv
ret i64 %add
}
; 'call' before the 'load' doesn't get optimized:
define i64 @test2(i32* nocapture readonly %a, i1 %b) {
; CHECK-LABEL: @test2
; CHECK-DAG: load i64* %1, align 4
; CHECK-DAG: tail call void @llvm.assume(i1 %b)
; CHECK: ret i64
%load1 = load i32* %a, align 4
%conv = zext i32 %load1 to i64
%arrayidx1 = getelementptr inbounds i32* %a, i64 1
tail call void @llvm.assume(i1 %b)
%load2 = load i32* %arrayidx1, align 4
%conv2 = zext i32 %load2 to i64
%shl = shl nuw i64 %conv2, 32
%add = or i64 %shl, %conv
ret i64 %add
}
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