| ; RUN: opt < %s -analyze -enable-new-pm=0 -scalar-evolution | FileCheck %s |
| ; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck %s |
| |
| ; ScalarEvolution should be able to compute trip count of the loop by proving |
| ; that this is not an infinite loop with side effects. |
| |
| ; CHECK: Determining loop execution counts for: @foo1 |
| ; CHECK: backedge-taken count is ((-1 + %n) /u %s) |
| |
| ; We should have a conservative estimate for the max backedge taken count for |
| ; loops with unknown stride. |
| ; CHECK: max backedge-taken count is -1 |
| |
| target datalayout = "e-m:e-p:32:32-f64:32:64-f80:32-n8:16:32-S128" |
| |
| ; Function Attrs: norecurse nounwind |
| define void @foo1(i32* nocapture %A, i32 %n, i32 %s) #0 { |
| entry: |
| %cmp4 = icmp sgt i32 %n, 0 |
| br i1 %cmp4, label %for.body, label %for.end |
| |
| for.body: ; preds = %entry, %for.body |
| %i.05 = phi i32 [ %add, %for.body ], [ 0, %entry ] |
| %arrayidx = getelementptr inbounds i32, i32* %A, i32 %i.05 |
| %0 = load i32, i32* %arrayidx, align 4 |
| %inc = add nsw i32 %0, 1 |
| store i32 %inc, i32* %arrayidx, align 4 |
| %add = add nsw i32 %i.05, %s |
| %cmp = icmp slt i32 %add, %n |
| br i1 %cmp, label %for.body, label %for.end |
| |
| for.end: ; preds = %for.body, %entry |
| ret void |
| } |
| |
| |
| ; Check that we are able to compute trip count of a loop without an entry guard. |
| ; CHECK: Determining loop execution counts for: @foo2 |
| ; CHECK: backedge-taken count is ((-1 + (%n smax %s)) /u %s) |
| |
| ; We should have a conservative estimate for the max backedge taken count for |
| ; loops with unknown stride. |
| ; CHECK: max backedge-taken count is -1 |
| |
| ; Function Attrs: norecurse nounwind |
| define void @foo2(i32* nocapture %A, i32 %n, i32 %s) #0 { |
| entry: |
| br label %for.body |
| |
| for.body: ; preds = %entry, %for.body |
| %i.05 = phi i32 [ %add, %for.body ], [ 0, %entry ] |
| %arrayidx = getelementptr inbounds i32, i32* %A, i32 %i.05 |
| %0 = load i32, i32* %arrayidx, align 4 |
| %inc = add nsw i32 %0, 1 |
| store i32 %inc, i32* %arrayidx, align 4 |
| %add = add nsw i32 %i.05, %s |
| %cmp = icmp slt i32 %add, %n |
| br i1 %cmp, label %for.body, label %for.end |
| |
| for.end: ; preds = %for.body, %entry |
| ret void |
| } |
| |