From 89d4e3c3fddffcb57c6d430e58d0404379f41a4e Mon Sep 17 00:00:00 2001
From: Dan Gohman <gohman@apple.com>
Date: Fri, 19 Mar 2010 21:51:03 +0000
Subject: [PATCH] Fix more places to more thoroughly ignore debug intrinsics.
 This fixes use-before-def errors in SCEVExpander-produced code in sqlite3
 when debug info with optimization is enabled, though the testcases for this
 are dependent on use-list order.

llvm-svn: 99001
---
 .../llvm/Analysis/ScalarEvolutionExpander.h    |  7 +------
 llvm/lib/Analysis/ScalarEvolutionExpander.cpp  | 18 +++++++++++++-----
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/llvm/include/llvm/Analysis/ScalarEvolutionExpander.h b/llvm/include/llvm/Analysis/ScalarEvolutionExpander.h
index 26dc0c4a54a6..828709404b10 100644
--- a/llvm/include/llvm/Analysis/ScalarEvolutionExpander.h
+++ b/llvm/include/llvm/Analysis/ScalarEvolutionExpander.h
@@ -79,12 +79,7 @@ namespace llvm {
     /// expandCodeFor - Insert code to directly compute the specified SCEV
     /// expression into the program.  The inserted code is inserted into the
     /// specified block.
-    Value *expandCodeFor(const SCEV *SH, const Type *Ty, Instruction *I) {
-      BasicBlock::iterator IP = I;
-      while (isInsertedInstruction(IP)) ++IP;
-      Builder.SetInsertPoint(IP->getParent(), IP);
-      return expandCodeFor(SH, Ty);
-    }
+    Value *expandCodeFor(const SCEV *SH, const Type *Ty, Instruction *I);
 
     /// setIVIncInsertPos - Set the current IV increment loop and position.
     void setIVIncInsertPos(const Loop *L, Instruction *Pos) {
diff --git a/llvm/lib/Analysis/ScalarEvolutionExpander.cpp b/llvm/lib/Analysis/ScalarEvolutionExpander.cpp
index e55ca53c9505..138cdc64cd0c 100644
--- a/llvm/lib/Analysis/ScalarEvolutionExpander.cpp
+++ b/llvm/lib/Analysis/ScalarEvolutionExpander.cpp
@@ -1240,6 +1240,15 @@ Value *SCEVExpander::visitUMaxExpr(const SCEVUMaxExpr *S) {
   return LHS;
 }
 
+Value *SCEVExpander::expandCodeFor(const SCEV *SH, const Type *Ty,
+                                   Instruction *I) {
+  BasicBlock::iterator IP = I;
+  while (isInsertedInstruction(IP) || isa<DbgInfoIntrinsic>(IP))
+    ++IP;
+  Builder.SetInsertPoint(IP->getParent(), IP);
+  return expandCodeFor(SH, Ty);
+}
+
 Value *SCEVExpander::expandCodeFor(const SCEV *SH, const Type *Ty) {
   // Expand the code for this SCEV.
   Value *V = expand(SH);
@@ -1278,9 +1287,7 @@ Value *SCEVExpander::expand(const SCEV *S) {
       // there) so that it is guaranteed to dominate any user inside the loop.
       if (L && S->hasComputableLoopEvolution(L) && L != PostIncLoop)
         InsertPt = L->getHeader()->getFirstNonPHI();
-      while (isa<DbgInfoIntrinsic>(InsertPt))
-        InsertPt = llvm::next(BasicBlock::iterator(InsertPt));
-      while (isInsertedInstruction(InsertPt))
+      while (isInsertedInstruction(InsertPt) || isa<DbgInfoIntrinsic>(InsertPt))
         InsertPt = llvm::next(BasicBlock::iterator(InsertPt));
       break;
     }
@@ -1316,7 +1323,8 @@ void SCEVExpander::rememberInstruction(Value *I) {
   // subsequently inserted code will be dominated.
   if (Builder.GetInsertPoint() == I) {
     BasicBlock::iterator It = cast<Instruction>(I);
-    do { ++It; } while (isInsertedInstruction(It));
+    do { ++It; } while (isInsertedInstruction(It) ||
+                        isa<DbgInfoIntrinsic>(It));
     Builder.SetInsertPoint(Builder.GetInsertBlock(), It);
   }
 }
@@ -1324,7 +1332,7 @@ void SCEVExpander::rememberInstruction(Value *I) {
 void SCEVExpander::restoreInsertPoint(BasicBlock *BB, BasicBlock::iterator I) {
   // If we acquired more instructions since the old insert point was saved,
   // advance past them.
-  while (isInsertedInstruction(I)) ++I;
+  while (isInsertedInstruction(I) || isa<DbgInfoIntrinsic>(I)) ++I;
 
   Builder.SetInsertPoint(BB, I);
 }