GBE: set memcpy and memset functions's linkage to LinkOnceAnyLinkage at last call.

LLVM IR pass will produce memcpy and memset, if set LinkOnceAnyLinkage,
memcpy and memset will be delete before and cause fail.

Signed-off-by: Yang Rong <rong.r.yang@intel.com>
Reviewed-by: Pan Xiuli <xiuli.pan@intel.com>

3 files changed, 14 insertions, 7 deletions

diff --git a/backend/src/llvm/StripAttributes.cpp b/backend/src/llvm/StripAttributes.cpp
index 9d07c29d..99e5a71e 100644
--- a/backend/src/llvm/StripAttributes.cpp
+++ b/backend/src/llvm/StripAttributes.cpp
@@ -79,10 +79,13 @@ namespace {
   class StripAttributes : public FunctionPass {
   public:
     static char ID; // Pass identification, replacement for typeid
-    StripAttributes() : FunctionPass(ID) {
+    StripAttributes(bool lastTime) : FunctionPass(ID),
+                                     lastTime(lastTime) {
     }
 
     virtual bool runOnFunction(Function &Func);
+  private:
+    bool lastTime; //last time all StripAttributes
   };
 }
 
@@ -93,7 +96,11 @@ bool StripAttributes::runOnFunction(Function &Func) {
   Func.setLinkage(GlobalValue::ExternalLinkage);
   if (!gbe::isKernelFunction(Func)) {
     Func.addFnAttr(Attribute::AlwaysInline);
-    Func.setLinkage(GlobalValue::LinkOnceAnyLinkage);
+    if (lastTime ||
+        (Func.getName().find("__gen_mem") == std::string::npos))
+      // Memcpy and memset functions could be deleted at last inline.
+      // Delete memcpy and memset functions for output llvm ir friendly.
+      Func.setLinkage(GlobalValue::LinkOnceAnyLinkage);
   }
 
   for (Function::iterator BB = Func.begin(), E = Func.end();
@@ -109,6 +116,6 @@ bool StripAttributes::runOnFunction(Function &Func) {
   return true;
 }
 
-FunctionPass *llvm::createStripAttributesPass() {
-  return new StripAttributes();
+FunctionPass *llvm::createStripAttributesPass(bool lastTime) {
+  return new StripAttributes(lastTime);
 }
diff --git a/backend/src/llvm/llvm_gen_backend.hpp b/backend/src/llvm/llvm_gen_backend.hpp
index 2a322ac1..b4715b15 100644
--- a/backend/src/llvm/llvm_gen_backend.hpp
+++ b/backend/src/llvm/llvm_gen_backend.hpp
@@ -46,7 +46,7 @@ namespace llvm {
   FunctionPass *createExpandConstantExprPass();
   FunctionPass *createExpandLargeIntegersPass();
   FunctionPass *createPromoteIntegersPass();
-  FunctionPass *createStripAttributesPass();
+  FunctionPass *createStripAttributesPass(bool lastTime);
   // Copy debug information from Original to New, and return New.
   template <typename T> T *CopyDebug(T *New, llvm::Instruction *Original) {
     New->setDebugLoc(Original->getDebugLoc());
diff --git a/backend/src/llvm/llvm_to_gen.cpp b/backend/src/llvm/llvm_to_gen.cpp
index 37919ec6..ceefbbb0 100644
--- a/backend/src/llvm/llvm_to_gen.cpp
+++ b/backend/src/llvm/llvm_to_gen.cpp
@@ -139,7 +139,7 @@ namespace gbe
     MPM.add(createBarrierNodupPass(false));   // remove noduplicate fnAttr before inlining.
     MPM.add(createFunctionInliningPass(20000));
     MPM.add(createBarrierNodupPass(true));    // restore noduplicate fnAttr after inlining.
-    MPM.add(createStripAttributesPass());     // Strip unsupported attributes and calling conventions.
+    MPM.add(createStripAttributesPass(false));     // Strip unsupported attributes and calling conventions.
     MPM.add(createSamplerFixPass());
     MPM.add(createGlobalOptimizerPass());     // Optimize out global vars
 
@@ -372,7 +372,7 @@ namespace gbe
 #endif
     // Print the code before further optimizations
     passes.add(createIntrinsicLoweringPass());
-    passes.add(createStripAttributesPass());     // Strip unsupported attributes and calling conventions.
+    passes.add(createStripAttributesPass(true));     // Strip unsupported attributes and calling conventions.
     passes.add(createFunctionInliningPass(20000));
 #if LLVM_VERSION_MAJOR * 10 + LLVM_VERSION_MINOR >= 37
     passes.add(createSROAPass());