Build the correct range for loops with unusual bounds. Fix from Jay Foad.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42394 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky 2007-09-27 14:12:54 +00:00
parent 0678f60bf2
commit 9a2f93121b
2 changed files with 22 additions and 1 deletions

View File

@ -2470,7 +2470,7 @@ SCEVHandle SCEVAddRecExpr::getNumIterationsInRange(ConstantRange Range) const {
APInt End = A.sge(One) ? (Range.getUpper() - One) : Range.getLower();
// The exit value should be (End+A)/A.
APInt ExitVal = (End + A).sdiv(A);
APInt ExitVal = (End + A).udiv(A);
ConstantInt *ExitValue = ConstantInt::get(ExitVal);
// Evaluate at the exit value. If we really did fall out of the valid

View File

@ -0,0 +1,21 @@
; RUN: llvm-as < %s | opt -analyze -scalar-evolution 2>&1 | grep "13 iterations"
; PR1706
define i32 @f() {
entry:
br label %bb5
bb: ; preds = %bb5
%tmp2 = shl i32 %j.0, 1 ; <i32> [#uses=1]
%tmp4 = add i32 %i.0, 268435456 ; <i32> [#uses=1]
br label %bb5
bb5: ; preds = %bb, %entry
%j.0 = phi i32 [ 1, %entry ], [ %tmp2, %bb ] ; <i32> [#uses=2]
%i.0 = phi i32 [ -1879048192, %entry ], [ %tmp4, %bb ] ; <i32> [#uses=2]
%tmp7 = icmp slt i32 %i.0, 1610612736 ; <i1> [#uses=1]
br i1 %tmp7, label %bb, label %return
return: ; preds = %bb5
ret i32 %j.0
}