[PATCH] D144051: [SCEV] Do not strengthen nuw/nsw flags during get[Zero,Sign]ExtendedExpr.

[Florian Hahn 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 rG484c622760e2: [SCEV] Do not strengthen nuw/nsw flags during get[Zero,Sign]ExtendedExpr. (authored by fhahn).

Changed prior to commit:
  https://reviews.llvm.org/D144051?vs=497457&id=505616#toc

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D144051/new/

https://reviews.llvm.org/D144051

Files:
  llvm/lib/Analysis/ScalarEvolution.cpp
  llvm/test/Transforms/IndVarSimplify/lftr-reuse.ll


Index: llvm/test/Transforms/IndVarSimplify/lftr-reuse.ll
===================================================================
--- llvm/test/Transforms/IndVarSimplify/lftr-reuse.ll
+++ llvm/test/Transforms/IndVarSimplify/lftr-reuse.ll
@@ -126,6 +126,8 @@
 
 ; Force SCEVExpander to look for an existing well-formed phi.
 ; Perform LFTR without generating extra preheader code.
+; TODO: Recover regression after not strengthening AddRec flags during
+; get[Sign,Zero]ExtendExpr for INDVARS_IV_NEXT.
 define void @guardedloop(ptr %matrix, ptr %vector,
 ;
 ; CHECK-LABEL: @guardedloop(
@@ -146,7 +148,7 @@
 ; CHECK-NEXT:    [[VECTORP:%.*]] = getelementptr inbounds [0 x double], ptr [[VECTOR:%.*]], i32 0, i64 [[INDVARS_IV2]]
 ; CHECK-NEXT:    [[V2:%.*]] = load double, ptr [[VECTORP]], align 8
 ; CHECK-NEXT:    call void @use(double [[V2]])
-; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], [[TMP0]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add i64 [[INDVARS_IV]], [[TMP0]]
 ; CHECK-NEXT:    [[INDVARS_IV_NEXT3]] = add nuw nsw i64 [[INDVARS_IV2]], 1
 ; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp ne i64 [[INDVARS_IV_NEXT3]], [[WIDE_TRIP_COUNT]]
 ; CHECK-NEXT:    br i1 [[EXITCOND]], label [[LOOP]], label [[RETURN_LOOPEXIT:%.*]]
Index: llvm/lib/Analysis/ScalarEvolution.cpp
===================================================================
--- llvm/lib/Analysis/ScalarEvolution.cpp
+++ llvm/lib/Analysis/ScalarEvolution.cpp
@@ -1625,11 +1625,6 @@
       unsigned BitWidth = getTypeSizeInBits(AR->getType());
       const Loop *L = AR->getLoop();
 
-      if (!AR->hasNoUnsignedWrap()) {
-        auto NewFlags = proveNoWrapViaConstantRanges(AR);
-        setNoWrapFlags(const_cast<SCEVAddRecExpr *>(AR), NewFlags);
-      }
-
       // If we have special knowledge that this addrec won't overflow,
       // we don't need to do any further analysis.
       if (AR->hasNoUnsignedWrap()) {
@@ -2009,11 +2004,6 @@
       unsigned BitWidth = getTypeSizeInBits(AR->getType());
       const Loop *L = AR->getLoop();
 
-      if (!AR->hasNoSignedWrap()) {
-        auto NewFlags = proveNoWrapViaConstantRanges(AR);
-        setNoWrapFlags(const_cast<SCEVAddRecExpr *>(AR), NewFlags);
-      }
-
       // If we have special knowledge that this addrec won't overflow,
       // we don't need to do any further analysis.
       if (AR->hasNoSignedWrap()) {


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D144051.505616.patch
Type: text/x-patch
Size: 2360 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20230315/493f36e6/attachment.bin>