| ; RUN: opt -analyze -enable-new-pm=0 -scalar-evolution < %s | FileCheck %s |
| ; RUN: opt -disable-output "-passes=print<scalar-evolution>" < %s 2>&1 | FileCheck %s |
| |
| ; An example run where SCEV(%postinc)->getStart() may overflow: |
| ; |
| ; %start = INT_SMAX |
| ; %low.limit = INT_SMIN |
| ; %high.limit = < not used > |
| ; |
| ; >> entry: |
| ; %postinc.start = INT_SMIN |
| ; |
| ; >> loop: |
| ; %idx = %start |
| ; %postinc = INT_SMIN |
| ; %postinc.inc = INT_SMIN + 1 |
| ; %postinc.sext = sext(INT_SMIN) = i64 INT32_SMIN |
| ; %break.early = INT_SMIN `slt` INT_SMIN = false |
| ; br i1 false, ___, %early.exit |
| ; |
| ; >> early.exit: |
| ; ret i64 INT32_SMIN |
| |
| |
| define i64 @bad.0(i32 %start, i32 %low.limit, i32 %high.limit) { |
| ; CHECK-LABEL: Classifying expressions for: @bad.0 |
| entry: |
| %postinc.start = add i32 %start, 1 |
| br label %loop |
| |
| loop: |
| %idx = phi i32 [ %start, %entry ], [ %idx.inc, %continue ] |
| %postinc = phi i32 [ %postinc.start, %entry ], [ %postinc.inc, %continue ] |
| %postinc.inc = add nsw i32 %postinc, 1 |
| %postinc.sext = sext i32 %postinc to i64 |
| ; CHECK: %postinc.sext = sext i32 %postinc to i64 |
| ; CHECK-NEXT: --> {(sext i32 (1 + %start) to i64),+,1}<nsw><%loop> |
| %break.early = icmp slt i32 %postinc, %low.limit |
| br i1 %break.early, label %continue, label %early.exit |
| |
| continue: |
| %idx.inc = add nsw i32 %idx, 1 |
| %cmp = icmp slt i32 %idx.inc, %high.limit |
| br i1 %cmp, label %loop, label %exit |
| |
| exit: |
| ret i64 0 |
| |
| early.exit: |
| ret i64 %postinc.sext |
| } |
| |
| define i64 @bad.1(i32 %start, i32 %low.limit, i32 %high.limit, i1* %unknown) { |
| ; CHECK-LABEL: Classifying expressions for: @bad.1 |
| entry: |
| %postinc.start = add i32 %start, 1 |
| br label %loop |
| |
| loop: |
| %idx = phi i32 [ %start, %entry ], [ %idx.inc, %continue ], [ %idx.inc, %continue.1 ] |
| %postinc = phi i32 [ %postinc.start, %entry ], [ %postinc.inc, %continue ], [ %postinc.inc, %continue.1 ] |
| %postinc.inc = add nsw i32 %postinc, 1 |
| %postinc.sext = sext i32 %postinc to i64 |
| ; CHECK: %postinc.sext = sext i32 %postinc to i64 |
| ; CHECK-NEXT: --> {(sext i32 (1 + %start) to i64),+,1}<nsw><%loop> |
| %break.early = icmp slt i32 %postinc, %low.limit |
| br i1 %break.early, label %continue.1, label %early.exit |
| |
| continue.1: |
| %cond = load volatile i1, i1* %unknown |
| %idx.inc = add nsw i32 %idx, 1 |
| br i1 %cond, label %loop, label %continue |
| |
| continue: |
| %cmp = icmp slt i32 %idx.inc, %high.limit |
| br i1 %cmp, label %loop, label %exit |
| |
| exit: |
| ret i64 0 |
| |
| early.exit: |
| ret i64 %postinc.sext |
| } |