[PATCH] D45180: libcalls must check for "RtLibUseGOT" metadata during simplification

Sriraman Tallam via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Tue Apr 10 16:38:01 PDT 2018


This revision was not accepted when it landed; it landed in state "Needs Review".
This revision was automatically updated to reflect the committed changes.
Closed by commit rL329768: Simplification of libcall like printf->puts must check for RtLibUseGOT metadata. (authored by tmsriram, committed by ).

Changed prior to commit:
  https://reviews.llvm.org/D45180?vs=141173&id=141929#toc

Repository:
  rL LLVM

https://reviews.llvm.org/D45180

Files:
  llvm/trunk/lib/Transforms/Utils/BuildLibCalls.cpp
  llvm/trunk/test/CodeGen/X86/no-plt-libcalls.ll


Index: llvm/trunk/lib/Transforms/Utils/BuildLibCalls.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Utils/BuildLibCalls.cpp
+++ llvm/trunk/lib/Transforms/Utils/BuildLibCalls.cpp
@@ -105,12 +105,23 @@
   return true;
 }
 
+static bool setNonLazyBind(Function &F) {
+  if (F.hasFnAttribute(Attribute::NonLazyBind))
+    return false;
+  F.addFnAttr(Attribute::NonLazyBind);
+  return true;
+}
+
 bool llvm::inferLibFuncAttributes(Function &F, const TargetLibraryInfo &TLI) {
   LibFunc TheLibFunc;
   if (!(TLI.getLibFunc(F, TheLibFunc) && TLI.has(TheLibFunc)))
     return false;
 
   bool Changed = false;
+
+  if (F.getParent() != nullptr && F.getParent()->getRtLibUseGOT())
+    Changed |= setNonLazyBind(F);
+
   switch (TheLibFunc) {
   case LibFunc_strlen:
   case LibFunc_wcslen:
Index: llvm/trunk/test/CodeGen/X86/no-plt-libcalls.ll
===================================================================
--- llvm/trunk/test/CodeGen/X86/no-plt-libcalls.ll
+++ llvm/trunk/test/CodeGen/X86/no-plt-libcalls.ll
@@ -0,0 +1,19 @@
+; Check if "RtLibUseGOT" works correctly when lib calls are simplified.
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+ at percent_s = constant [4 x i8] c"%s\0A\00"
+ at hello_world = constant [13 x i8] c"hello world\0A\00"
+declare i32 @printf(i8*, ...)
+define void @printf_call() {
+  %fmt = getelementptr [4 x i8], [4 x i8]* @percent_s, i32 0, i32 0
+  %str = getelementptr [13 x i8], [13 x i8]* @hello_world, i32 0, i32 0
+  call i32 (i8*, ...) @printf(i8* %fmt, i8* %str)
+; CHECK:  call i32 @puts(i8* getelementptr inbounds ([13 x i8], [13 x i8]* @hello_world, i64 0, i64 0))
+  ret void
+}
+
+; CHECK: Function Attrs: nounwind nonlazybind
+; CHECK-NEXT: declare i32 @puts(i8* nocapture readonly)
+
+!llvm.module.flags = !{!0}
+!0 = !{i32 7, !"RtLibUseGOT", i32 1}


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D45180.141929.patch
Type: text/x-patch
Size: 1853 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20180410/c972ac92/attachment.bin>


More information about the llvm-commits mailing list