Make MemoryBuiltins aware of TargetLibraryInfo.

This disables malloc-specific optimization when -fno-builtin (or -ffreestanding)
is specified. This has been a problem for a long time but became more severe
with the recent memory builtin improvements.

Since the memory builtin functions are used everywhere, this required passing
TLI in many places. This means that functions that now have an optional TLI
argument, like RecursivelyDeleteTriviallyDeadFunctions, won't remove dead
mallocs anymore if the TLI argument is missing. I've updated most passes to do
the right thing.

Fixes PR13694 and probably others.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162841 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 11 insertions, 6 deletions

diff --git a/include/llvm/Transforms/Utils/BasicBlockUtils.h b/include/llvm/Transforms/Utils/BasicBlockUtils.h
index 8a939cc75e..2510aecc69 100644
--- a/include/llvm/Transforms/Utils/BasicBlockUtils.h
+++ b/include/llvm/Transforms/Utils/BasicBlockUtils.h
@@ -27,6 +27,7 @@ class AliasAnalysis;
 class Instruction;
 class Pass;
 class ReturnInst;
+class TargetLibraryInfo;
 
 /// DeleteDeadBlock - Delete the specified block, which must have no
 /// predecessors.
@@ -44,7 +45,7 @@ void FoldSingleEntryPHINodes(BasicBlock *BB, Pass *P = 0);
 /// a result. This includes tracing the def-use list from the PHI to see if
 /// it is ultimately unused or if it reaches an unused cycle. Return true
 /// if any PHIs were deleted.
-bool DeleteDeadPHIs(BasicBlock *BB);
+bool DeleteDeadPHIs(BasicBlock *BB, const TargetLibraryInfo *TLI = 0);
 
 /// MergeBlockIntoPredecessor - Attempts to merge a block into its predecessor,
 /// if possible.  The return value indicates success or failure.
diff --git a/include/llvm/Transforms/Utils/Local.h b/include/llvm/Transforms/Utils/Local.h
index 495eab7328..83f0e7a4bd 100644
--- a/include/llvm/Transforms/Utils/Local.h
+++ b/include/llvm/Transforms/Utils/Local.h
@@ -36,6 +36,7 @@ class PHINode;
 class AllocaInst;
 class ConstantExpr;
 class TargetData;
+class TargetLibraryInfo;
 class DIBuilder;
 
 template<typename T> class SmallVectorImpl;
@@ -51,7 +52,8 @@ template<typename T> class SmallVectorImpl;
 /// Also calls RecursivelyDeleteTriviallyDeadInstructions() on any branch/switch
 /// conditions and indirectbr addresses this might make dead if
 /// DeleteDeadConditions is true.
-bool ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions = false);
+bool ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions = false,
+                            const TargetLibraryInfo *TLI = 0);
 
 //===----------------------------------------------------------------------===//
 //  Local dead code elimination.
@@ -60,20 +62,21 @@ bool ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions = false);
 /// isInstructionTriviallyDead - Return true if the result produced by the
 /// instruction is not used, and the instruction has no side effects.
 ///
-bool isInstructionTriviallyDead(Instruction *I);
+bool isInstructionTriviallyDead(Instruction *I, const TargetLibraryInfo *TLI=0);
 
 /// RecursivelyDeleteTriviallyDeadInstructions - If the specified value is a
 /// trivially dead instruction, delete it.  If that makes any of its operands
 /// trivially dead, delete them too, recursively.  Return true if any
 /// instructions were deleted.
-bool RecursivelyDeleteTriviallyDeadInstructions(Value *V);
+bool RecursivelyDeleteTriviallyDeadInstructions(Value *V,
+                                                const TargetLibraryInfo *TLI=0);
 
 /// RecursivelyDeleteDeadPHINode - If the specified value is an effectively
 /// dead PHI node, due to being a def-use chain of single-use nodes that
 /// either forms a cycle or is terminated by a trivially dead instruction,
 /// delete it.  If that makes any of its operands trivially dead, delete them
 /// too, recursively.  Return true if a change was made.
-bool RecursivelyDeleteDeadPHINode(PHINode *PN);
+bool RecursivelyDeleteDeadPHINode(PHINode *PN, const TargetLibraryInfo *TLI=0);
 
   
 /// SimplifyInstructionsInBlock - Scan the specified basic block and try to
@@ -81,7 +84,8 @@ bool RecursivelyDeleteDeadPHINode(PHINode *PN);
 ///
 /// This returns true if it changed the code, note that it can delete
 /// instructions in other blocks as well in this block.
-bool SimplifyInstructionsInBlock(BasicBlock *BB, const TargetData *TD = 0);
+bool SimplifyInstructionsInBlock(BasicBlock *BB, const TargetData *TD = 0,
+                                 const TargetLibraryInfo *TLI = 0);
     
 //===----------------------------------------------------------------------===//
 //  Control Flow Graph Restructuring.