Now that we have ghost linkage, we can force resolution of external symbols
immediately instead of lazily.
In this program, for example:
int main() {
printf("hello world\n");
printf("hello world\n");
printf("hello world\n");
printf("hello world\n");
}
We used to have to go through compilation callback 4 times (once for each
call to printf), now we don't go to it at all.
Thanks to Misha for noticing this, and for adding the initial ghost linkage
patches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17864 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ExecutionEngine/JIT/JITEmitter.cpp b/lib/ExecutionEngine/JIT/JITEmitter.cpp
index 63bec96..878c3c33b 100644
--- a/lib/ExecutionEngine/JIT/JITEmitter.cpp
+++ b/lib/ExecutionEngine/JIT/JITEmitter.cpp
@@ -213,9 +213,14 @@
uint64_t Emitter::getGlobalValueAddress(GlobalValue *V) {
// Try looking up the function to see if it is already compiled, if not return
// 0.
- if (isa<Function>(V))
- return (intptr_t)TheJIT->getPointerToGlobalIfAvailable(V);
- else {
+ if (Function *F = dyn_cast<Function>(V)) {
+ void *Addr = TheJIT->getPointerToGlobalIfAvailable(F);
+ if (Addr == 0 && F->hasExternalLinkage()) {
+ // Do not output stubs for external functions.
+ Addr = TheJIT->getPointerToFunction(F);
+ }
+ return (intptr_t)Addr;
+ } else {
return (intptr_t)TheJIT->getOrEmitGlobalVariable(cast<GlobalVariable>(V));
}
}