doesNotAccessMemory, check doesNotAccessMemory
first, since otherwise functions may be
marked readonly rather than readnone.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55697
91177308-0d34-0410-b5e6-
96231b3b80d8
if (F->isDeclaration()) {
// Try to get mod/ref behaviour from function attributes.
if (F->isDeclaration()) {
// Try to get mod/ref behaviour from function attributes.
- if (F->onlyReadsMemory()) {
+ if (F->doesNotAccessMemory()) {
+ // Can't do better than that!
+ } else if (F->onlyReadsMemory()) {
FunctionEffect |= Ref;
// This function might call back into the module and read a global, so
// mark all globals read somewhere as being read by this function.
for (std::set<GlobalValue*>::iterator GI = ReadGlobals.begin(),
E = ReadGlobals.end(); GI != E; ++GI)
FR.GlobalInfo[*GI] |= Ref;
FunctionEffect |= Ref;
// This function might call back into the module and read a global, so
// mark all globals read somewhere as being read by this function.
for (std::set<GlobalValue*>::iterator GI = ReadGlobals.begin(),
E = ReadGlobals.end(); GI != E; ++GI)
FR.GlobalInfo[*GI] |= Ref;
- } else if (!F->doesNotAccessMemory()) {
// Can't say anything useful.
KnowNothing = true;
}
// Can't say anything useful.
KnowNothing = true;
}
--- /dev/null
+; RUN: llvm-as < %s | opt -globalsmodref-aa -markmodref | llvm-dis | grep readnone | count 2
+
+define i32 @f() {
+entry:
+ %tmp = call i32 @e( ) ; <i32> [#uses=1]
+ ret i32 %tmp
+}
+
+declare i32 @e() readnone