Avoid creating canonical induction variables for non-native types.
For example, on 32-bit architecture, don't promote all uses of the IV
to 64-bits just because one use is a 64-bit cast.
Alternate implementation of the patch by Arnaud de Grandmaison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127884 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/IVUsers.cpp b/lib/Analysis/IVUsers.cpp
index c838218..2cda791 100644
--- a/lib/Analysis/IVUsers.cpp
+++ b/lib/Analysis/IVUsers.cpp
@@ -21,6 +21,7 @@
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
+#include "llvm/Target/TargetData.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/Debug.h"
@@ -83,7 +84,10 @@
return false; // Void and FP expressions cannot be reduced.
// LSR is not APInt clean, do not touch integers bigger than 64-bits.
- if (SE->getTypeSizeInBits(I->getType()) > 64)
+ // Also avoid creating IVs of non-native types. For example, we don't want a
+ // 64-bit IV in 32-bit code just because the loop has one 64-bit cast.
+ uint64_t Width = SE->getTypeSizeInBits(I->getType());
+ if (Width > 64 || (TD && !TD->isLegalInteger(Width)))
return false;
if (!Processed.insert(I))
@@ -167,6 +171,7 @@
LI = &getAnalysis<LoopInfo>();
DT = &getAnalysis<DominatorTree>();
SE = &getAnalysis<ScalarEvolution>();
+ TD = getAnalysisIfAvailable<TargetData>();
// Find all uses of induction variables in this loop, and categorize
// them by stride. Start by finding all of the PHI nodes in the header for