refactor the MemoryBuiltin analysis:

 - provide more extensive set of functions to detect library allocation functions (e.g., malloc, calloc, strdup, etc)
 - provide an API to compute the size and offset of an object pointed by

Move a few clients (GVN, AA, instcombine, ...) to the new API.
This implementation is a lot more aggressive than each of the custom implementations being replaced.

Patch reviewed by Nick Lewycky and Chandler Carruth, thanks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158919 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index 52f31b1..1b886fd 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -1436,7 +1436,7 @@ bool GVN::processNonLocalLoad(LoadInst *LI) {
     Instruction *DepInst = DepInfo.getInst();
 
     // Loading the allocation -> undef.
-    if (isa<AllocaInst>(DepInst) || isMalloc(DepInst) ||
+    if (isa<AllocaInst>(DepInst) || isMallocLikeFn(DepInst) ||
         // Loading immediately after lifetime begin -> undef.
         isLifetimeStart(DepInst)) {
       ValuesPerBlock.push_back(AvailableValueInBlock::get(DepBB,
@@ -1951,7 +1951,7 @@ bool GVN::processLoad(LoadInst *L) {
   // If this load really doesn't depend on anything, then we must be loading an
   // undef value.  This can happen when loading for a fresh allocation with no
   // intervening stores, for example.
-  if (isa<AllocaInst>(DepInst) || isMalloc(DepInst)) {
+  if (isa<AllocaInst>(DepInst) || isMallocLikeFn(DepInst)) {
     L->replaceAllUsesWith(UndefValue::get(L->getType()));
     markInstructionForDeletion(L);
     ++NumGVNLoad;