Please use GitHub pull requests for new patches. Phabricator shutdown timeline
Changeset View
Changeset View
Standalone View
Standalone View
llvm/test/Analysis/ScalarEvolution/trip-count-unknown-stride.ll
| ; RUN: opt < %s -analyze -scalar-evolution | 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 | |||||
| } | |||||