SCEVExpander: Fix a regression I introduced by to eagerly adding RAII objects.

PR17425.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191741 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 47 insertions, 1 deletions

diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp
index 1ab989f..f373a80 100644
--- a/lib/Analysis/ScalarEvolutionExpander.cpp
+++ b/lib/Analysis/ScalarEvolutionExpander.cpp
@@ -569,7 +569,7 @@ Value *SCEVExpander::expandAddToGEP(const SCEV *const *op_begin,
   }
 
   // Save the original insertion point so we can restore it when we're done.
-  BuilderType::InsertPointGuard Guard(Builder);
+  BuilderType::InsertPoint SaveInsertPt = Builder.saveIP();
 
   // Move the insertion point out of as many loops as we can.
   while (const Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock())) {
@@ -604,6 +604,9 @@ Value *SCEVExpander::expandAddToGEP(const SCEV *const *op_begin,
   Ops.push_back(SE.getUnknown(GEP));
   rememberInstruction(GEP);
 
+  // Restore the original insert point.
+  Builder.restoreIP(SaveInsertPt);
+
   return expand(SE.getAddExpr(Ops));
 }
 
diff --git a/test/Transforms/LoopStrengthReduce/dominate-assert.ll b/test/Transforms/LoopStrengthReduce/dominate-assert.ll
index ff8cab8..3ba93ff 100644
--- a/test/Transforms/LoopStrengthReduce/dominate-assert.ll
+++ b/test/Transforms/LoopStrengthReduce/dominate-assert.ll
@@ -68,3 +68,46 @@ bb7:
           catch i8* null
   ret void
 }
+
+; PR17425
+define void @i() {
+entry:
+  br label %while.cond
+
+while.cond:                                       ; preds = %while.cond, %entry
+  %c.0 = phi i16* [ undef, %entry ], [ %incdec.ptr, %while.cond ]
+  %incdec.ptr = getelementptr inbounds i16* %c.0, i64 1
+  br i1 undef, label %while.cond1, label %while.cond
+
+while.cond1:                                      ; preds = %while.cond1, %while.cond
+  %c.1 = phi i16* [ %incdec.ptr5, %while.cond1 ], [ %c.0, %while.cond ]
+  %incdec.ptr5 = getelementptr inbounds i16* %c.1, i64 1
+  br i1 undef, label %while.cond7, label %while.cond1
+
+while.cond7:                                      ; preds = %while.cond7, %while.cond1
+  %0 = phi i16* [ %incdec.ptr10, %while.cond7 ], [ %c.1, %while.cond1 ]
+  %incdec.ptr10 = getelementptr inbounds i16* %0, i64 1
+  br i1 undef, label %while.cond12.preheader, label %while.cond7
+
+while.cond12.preheader:                           ; preds = %while.cond7
+  br i1 undef, label %while.end16, label %while.body13.lr.ph
+
+while.body13:                                     ; preds = %if.else, %while.body13.lr.ph
+  %1 = phi i16* [ %2, %while.body13.lr.ph ], [ %incdec.ptr15, %if.else ]
+  br i1 undef, label %while.cond12.outer.loopexit, label %if.else
+
+while.cond12.outer.loopexit:                      ; preds = %while.body13
+  br i1 undef, label %while.end16, label %while.body13.lr.ph
+
+while.body13.lr.ph:                               ; preds = %while.cond12.outer.loopexit, %while.cond12.preheader
+  %2 = phi i16* [ %1, %while.cond12.outer.loopexit ], [ undef, %while.cond12.preheader ]
+  br label %while.body13
+
+if.else:                                          ; preds = %while.body13
+  %incdec.ptr15 = getelementptr inbounds i16* %1, i64 1
+  %cmp = icmp eq i16* %incdec.ptr15, %0
+  br i1 %cmp, label %while.end16, label %while.body13
+
+while.end16:                                      ; preds = %if.else, %while.cond12.outer.loopexit, %while.cond12.preheader
+  ret void
+}