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

1 files changed, 2 insertions, 1 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.