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.

llvm-svn: 162841

1 files changed, 3 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/IPO/Inliner.cpp b/llvm/lib/Transforms/IPO/Inliner.cpp
index 712888aee9e..69a22fb1e60 100644
--- a/llvm/lib/Transforms/IPO/Inliner.cpp
+++ b/llvm/lib/Transforms/IPO/Inliner.cpp
@@ -20,6 +20,7 @@
 #include "llvm/Analysis/CallGraph.h"
 #include "llvm/Analysis/InlineCost.h"
 #include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetLibraryInfo.h"
 #include "llvm/Transforms/IPO/InlinerPass.h"
 #include "llvm/Transforms/Utils/Cloning.h"
 #include "llvm/Transforms/Utils/Local.h"
@@ -339,6 +340,7 @@ static bool InlineHistoryIncludes(Function *F, int InlineHistoryID,
 bool Inliner::runOnSCC(CallGraphSCC &SCC) {
   CallGraph &CG = getAnalysis<CallGraph>();
   const TargetData *TD = getAnalysisIfAvailable<TargetData>();
+  const TargetLibraryInfo *TLI = getAnalysisIfAvailable<TargetLibraryInfo>();
 
   SmallPtrSet<Function*, 8> SCCFunctions;
   DEBUG(dbgs() << "Inliner visiting SCC:");
@@ -417,7 +419,7 @@ bool Inliner::runOnSCC(CallGraphSCC &SCC) {
       // just delete the call instead of trying to inline it, regardless of
       // size.  This happens because IPSCCP propagates the result out of the
       // call and then we're left with the dead call.
-      if (isInstructionTriviallyDead(CS.getInstruction())) {
+      if (isInstructionTriviallyDead(CS.getInstruction(), TLI)) {
         DEBUG(dbgs() << "    -> Deleting dead call: "
                      << *CS.getInstruction() << "\n");
         // Update the call graph by deleting the edge from Callee to Caller.