| ; RUN: opt -S -passes=loop-load-elim < %s | FileCheck %s |
| |
| ; We can't hoist conditional loads to the preheader for the initial value. |
| ; E.g. in the loop below we'd access array[-1] if we did: |
| ; |
| ; for(int i = 0 ; i < n ; i++ ) |
| ; array[i] = ( i > 0 ? array[i - 1] : 0 ) + 4; |
| |
| target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" |
| target triple = "x86_64-apple-macosx10.11.0" |
| |
| define void @f(ptr %array, i32 %n) { |
| entry: |
| %cmp10 = icmp sgt i32 %n, 0 |
| br i1 %cmp10, label %for.body, label %for.cond.cleanup |
| |
| for.cond.cleanup: ; preds = %cond.end, %entry |
| ret void |
| |
| for.body: ; preds = %entry, %cond.end |
| %indvars.iv = phi i64 [ %indvars.iv.next, %cond.end ], [ 0, %entry ] |
| ; CHECK-NOT: %store_forwarded = phi |
| %cmp1 = icmp sgt i64 %indvars.iv, 0 |
| br i1 %cmp1, label %cond.true, label %cond.end |
| |
| cond.true: ; preds = %for.body |
| %0 = add nsw i64 %indvars.iv, -1 |
| %arrayidx = getelementptr inbounds i32, ptr %array, i64 %0 |
| %1 = load i32, ptr %arrayidx, align 4 |
| br label %cond.end |
| |
| cond.end: ; preds = %for.body, %cond.true |
| %cond = phi i32 [ %1, %cond.true ], [ 0, %for.body ] |
| ; CHECK: %cond = phi i32 [ %1, %cond.true ], [ 0, %for.body ] |
| %add = add nsw i32 %cond, 4 |
| %arrayidx3 = getelementptr inbounds i32, ptr %array, i64 %indvars.iv |
| store i32 %add, ptr %arrayidx3, align 4 |
| %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 |
| %lftr.wideiv = trunc i64 %indvars.iv.next to i32 |
| %exitcond = icmp eq i32 %lftr.wideiv, %n |
| br i1 %exitcond, label %for.cond.cleanup, label %for.body |
| } |