; RUN: opt -basicaa -loop-load-elim -S < %s | FileCheck %s ; When optimizing for size don't eliminate in this loop because the loop would ; have to be versioned first because A and C may alias. ; ; for (unsigned i = 0; i < 100; i++) { ; A[i+1] = B[i] + 2; ; C[i] = A[i] * 2; ; } target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" ; CHECK-LABEL: @f( define void @f(i32* %A, i32* %B, i32* %C, i64 %N) optsize { entry: br label %for.body for.body: ; preds = %for.body, %entry %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 %Aidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next %Bidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv %Cidx = getelementptr inbounds i32, i32* %C, i64 %indvars.iv %Aidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv %b = load i32, i32* %Bidx, align 4 %a_p1 = add i32 %b, 2 store i32 %a_p1, i32* %Aidx_next, align 4 %a = load i32, i32* %Aidx, align 4 ; CHECK: %c = mul i32 %a, 2 %c = mul i32 %a, 2 store i32 %c, i32* %Cidx, align 4 %exitcond = icmp eq i64 %indvars.iv.next, %N br i1 %exitcond, label %for.end, label %for.body for.end: ; preds = %for.body ret void } ; Same loop but with noalias on %A and %C. In this case load-eliminate even ; with -Os. ; CHECK-LABEL: @g( define void @g(i32* noalias %A, i32* %B, i32* noalias %C, i64 %N) optsize { entry: br label %for.body for.body: ; preds = %for.body, %entry %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 %Aidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next %Bidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv %Cidx = getelementptr inbounds i32, i32* %C, i64 %indvars.iv %Aidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv %b = load i32, i32* %Bidx, align 4 %a_p1 = add i32 %b, 2 store i32 %a_p1, i32* %Aidx_next, align 4 %a = load i32, i32* %Aidx, align 4 ; CHECK: %c = mul i32 %store_forwarded, 2 %c = mul i32 %a, 2 store i32 %c, i32* %Cidx, align 4 %exitcond = icmp eq i64 %indvars.iv.next, %N br i1 %exitcond, label %for.end, label %for.body for.end: ; preds = %for.body ret void }