[llvm-commits] [llvm] r130661 - in /llvm/trunk: include/llvm/Target/TargetLibraryInfo.h lib/Transforms/Scalar/MemCpyOptimizer.cpp

[Chris Lattner]

Author: lattner
Date: Sun May  1 13:27:11 2011
New Revision: 130661

URL: http://llvm.org/viewvc/llvm-project?rev=130661&view=rev
Log:
enhance memcpyopt to obey -fno-builtin and friends.  This addresses a
problem reported on cfe-dev.

Modified:
    llvm/trunk/include/llvm/Target/TargetLibraryInfo.h
    llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp

Modified: llvm/trunk/include/llvm/Target/TargetLibraryInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetLibraryInfo.h?rev=130661&r1=130660&r2=130661&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Target/TargetLibraryInfo.h (original)
+++ llvm/trunk/include/llvm/Target/TargetLibraryInfo.h Sun May  1 13:27:11 2011
@@ -23,6 +23,9 @@
       // void *memcpy(void *s1, const void *s2, size_t n);
       memcpy,
       
+      // void *memmove(void *s1, const void *s2, size_t n);
+      memmove,
+      
       /// void memset_pattern16(void *b, const void *pattern16, size_t len);
       memset_pattern16,
       

Modified: llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp?rev=130661&r1=130660&r2=130661&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp Sun May  1 13:27:11 2011
@@ -28,6 +28,7 @@
 #include "llvm/Support/IRBuilder.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetLibraryInfo.h"
 #include <list>
 using namespace llvm;
 
@@ -299,12 +300,15 @@
 namespace {
   class MemCpyOpt : public FunctionPass {
     MemoryDependenceAnalysis *MD;
+    TargetLibraryInfo *TLI;
     const TargetData *TD;
   public:
     static char ID; // Pass identification, replacement for typeid
     MemCpyOpt() : FunctionPass(ID) {
       initializeMemCpyOptPass(*PassRegistry::getPassRegistry());
       MD = 0;
+      TLI = 0;
+      TD = 0;
     }
 
     bool runOnFunction(Function &F);
@@ -316,6 +320,7 @@
       AU.addRequired<DominatorTree>();
       AU.addRequired<MemoryDependenceAnalysis>();
       AU.addRequired<AliasAnalysis>();
+      AU.addRequired<TargetLibraryInfo>();
       AU.addPreserved<AliasAnalysis>();
       AU.addPreserved<MemoryDependenceAnalysis>();
     }
@@ -346,6 +351,7 @@
                       false, false)
 INITIALIZE_PASS_DEPENDENCY(DominatorTree)
 INITIALIZE_PASS_DEPENDENCY(MemoryDependenceAnalysis)
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
 INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
 INITIALIZE_PASS_END(MemCpyOpt, "memcpyopt", "MemCpy Optimization",
                     false, false)
@@ -804,6 +810,9 @@
 bool MemCpyOpt::processMemMove(MemMoveInst *M) {
   AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
 
+  if (!TLI->has(LibFunc::memmove))
+    return false;
+  
   // See if the pointers alias.
   if (!AA.isNoAlias(AA.getLocationForDest(M), AA.getLocationForSource(M)))
     return false;
@@ -935,6 +944,14 @@
   bool MadeChange = false;
   MD = &getAnalysis<MemoryDependenceAnalysis>();
   TD = getAnalysisIfAvailable<TargetData>();
+  TLI = &getAnalysis<TargetLibraryInfo>();
+  
+  // If we don't have at least memset and memcpy, there is little point of doing
+  // anything here.  These are required by a freestanding implementation, so if
+  // even they are disabled, there is no point in trying hard.
+  if (!TLI->has(LibFunc::memset) || !TLI->has(LibFunc::memcpy))
+    return false;
+  
   while (1) {
     if (!iterateOnFunction(F))
       break;