[PATCH] D109546: [ScalarEvolution] Add an additional bailout to avoid NOT of pointer.

[Philip Reames via Phabricator via llvm-commits]

This revision was landed with ongoing or failed builds.
This revision was automatically updated to reflect the committed changes.
Closed by commit rGbfa2a81e926f: [ScalarEvolution] Add an additional bailout to avoid NOT of pointer. (authored by reames).

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D109546/new/

https://reviews.llvm.org/D109546

Files:
  llvm/lib/Analysis/ScalarEvolution.cpp


Index: llvm/lib/Analysis/ScalarEvolution.cpp
===================================================================
--- llvm/lib/Analysis/ScalarEvolution.cpp
+++ llvm/lib/Analysis/ScalarEvolution.cpp
@@ -4127,6 +4127,8 @@
 
 /// Return a SCEV corresponding to ~V = -1-V
 const SCEV *ScalarEvolution::getNotSCEV(const SCEV *V) {
+  assert(!V->getType()->isPointerTy() && "Can't negate pointer");
+
   if (const SCEVConstant *VC = dyn_cast<SCEVConstant>(V))
     return getConstant(
                 cast<ConstantInt>(ConstantExpr::getNot(VC->getValue())));
@@ -10672,15 +10674,21 @@
     if (!isa<SCEVConstant>(FoundRHS) && !isa<SCEVAddRecExpr>(FoundLHS))
       return isImpliedCondOperands(Pred, LHS, RHS, FoundRHS, FoundLHS, Context);
 
-    // Don't try to getNotSCEV pointers.
-    if (LHS->getType()->isPointerTy() || FoundLHS->getType()->isPointerTy())
-      return false;
+    // There's no clear preference between forms 3. and 4., try both.  Avoid
+    // forming getNotSCEV of pointer values as the resulting subtract is
+    // not legal.
+    if (!LHS->getType()->isPointerTy() && !RHS->getType()->isPointerTy() &&
+        isImpliedCondOperands(FoundPred, getNotSCEV(LHS), getNotSCEV(RHS),
+                              FoundLHS, FoundRHS, Context))
+      return true;
 
-    // There's no clear preference between forms 3. and 4., try both.
-    return isImpliedCondOperands(FoundPred, getNotSCEV(LHS), getNotSCEV(RHS),
-                                 FoundLHS, FoundRHS, Context) ||
-           isImpliedCondOperands(Pred, LHS, RHS, getNotSCEV(FoundLHS),
-                                 getNotSCEV(FoundRHS), Context);
+    if (!FoundLHS->getType()->isPointerTy() &&
+        !FoundRHS->getType()->isPointerTy() &&
+        isImpliedCondOperands(Pred, LHS, RHS, getNotSCEV(FoundLHS),
+                              getNotSCEV(FoundRHS), Context))
+      return true;
+
+    return false;
   }
 
   // Unsigned comparison is the same as signed comparison when both the operands


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D109546.371731.patch
Type: text/x-patch
Size: 1996 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20210909/9141280d/attachment.bin>