[llvm-commits] [llvm] r42394 - in /llvm/trunk: lib/Analysis/ScalarEvolution.cpp test/Analysis/ScalarEvolution/2007-09-27-LargeStepping.ll

[Nick Lewycky]

Author: nicholas
Date: Thu Sep 27 09:12:54 2007
New Revision: 42394

URL: http://llvm.org/viewvc/llvm-project?rev=42394&view=rev
Log:
Build the correct range for loops with unusual bounds. Fix from Jay Foad.

Added:
    llvm/trunk/test/Analysis/ScalarEvolution/2007-09-27-LargeStepping.ll
Modified:
    llvm/trunk/lib/Analysis/ScalarEvolution.cpp

Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=42394&r1=42393&r2=42394&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Thu Sep 27 09:12:54 2007
@@ -2470,7 +2470,7 @@
     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

Added: llvm/trunk/test/Analysis/ScalarEvolution/2007-09-27-LargeStepping.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/ScalarEvolution/2007-09-27-LargeStepping.ll?rev=42394&view=auto

==============================================================================
--- llvm/trunk/test/Analysis/ScalarEvolution/2007-09-27-LargeStepping.ll (added)
+++ llvm/trunk/test/Analysis/ScalarEvolution/2007-09-27-LargeStepping.ll Thu Sep 27 09:12:54 2007
@@ -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
+}