[llvm-commits] [llvm] r56247 - in /llvm/trunk: lib/Analysis/ScalarEvolution.cpp test/Analysis/ScalarEvolution/2008-02-11-ReversedCondition.ll test/Analysis/ScalarEvolution/avoid-smax-1.ll

[Dan Gohman]

Author: djg
Date: Tue Sep 16 13:52:57 2008
New Revision: 56247

URL: http://llvm.org/viewvc/llvm-project?rev=56247&view=rev
Log:
Finally re-apply r46959. This is made feasible by the combination
of r56230, r56232, and r56246.

Modified:
    llvm/trunk/lib/Analysis/ScalarEvolution.cpp
    llvm/trunk/test/Analysis/ScalarEvolution/2008-02-11-ReversedCondition.ll
    llvm/trunk/test/Analysis/ScalarEvolution/avoid-smax-1.ll

Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=56247&r1=56246&r2=56247&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Tue Sep 16 13:52:57 2008
@@ -1981,8 +1981,8 @@
 
   // At this point, we would like to compute how many iterations of the 
   // loop the predicate will return true for these inputs.
-  if (isa<SCEVConstant>(LHS) && !isa<SCEVConstant>(RHS)) {
-    // If there is a constant, force it into the RHS.
+  if (LHS->isLoopInvariant(L) && !RHS->isLoopInvariant(L)) {
+    // If there is a loop-invariant, force it into the RHS.
     std::swap(LHS, RHS);
     Cond = ICmpInst::getSwappedPredicate(Cond);
   }

Modified: llvm/trunk/test/Analysis/ScalarEvolution/2008-02-11-ReversedCondition.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/ScalarEvolution/2008-02-11-ReversedCondition.ll?rev=56247&r1=56246&r2=56247&view=diff

==============================================================================
--- llvm/trunk/test/Analysis/ScalarEvolution/2008-02-11-ReversedCondition.ll (original)
+++ llvm/trunk/test/Analysis/ScalarEvolution/2008-02-11-ReversedCondition.ll Tue Sep 16 13:52:57 2008
@@ -1,5 +1,4 @@
 ; RUN: llvm-as < %s | opt -scalar-evolution -analyze | grep {Loop header: (0 smax %n) iterations!}
-; XFAIL: *
 
 define void @foo(i32 %n) {
 entry:

Modified: llvm/trunk/test/Analysis/ScalarEvolution/avoid-smax-1.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/ScalarEvolution/avoid-smax-1.ll?rev=56247&r1=56246&r2=56247&view=diff

==============================================================================
--- llvm/trunk/test/Analysis/ScalarEvolution/avoid-smax-1.ll (original)
+++ llvm/trunk/test/Analysis/ScalarEvolution/avoid-smax-1.ll Tue Sep 16 13:52:57 2008
@@ -1,11 +1,13 @@
 ; RUN: llvm-as < %s | opt -indvars | llvm-dis > %t
-; RUN: not grep select %t
+; RUN: grep select %t | count 2
 ; RUN: grep {icmp ne i32.\* %w	} %t
 
 ; Indvars should be able to insert a canonical induction variable
 ; for the bb6 loop without using a maximum calculation (icmp, select)
 ; because it should be able to prove that the comparison is guarded
-; by an appropriate conditional branch.
+; by an appropriate conditional branch. Unfortunately, indvars is
+; not yet able to find the comparison for the other too loops in
+; this testcase.
 
 target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
 target triple = "i386-apple-darwin9"