Rollup merge of #65720 - icefoxen:LLVMgetInstructionCount, r=rkruppe

Add FFI bindings for LLVM's Module::getInstructionCount()

Just to make it usable for profiling and such inside
rustc itself.  It was vaguely useful in
https://wiki.alopex.li/WhereRustcSpendsItsTime and I figured
I might as well upstream it; I may or may not ever get around
to doing more with it (hopefully I will), but it may be useful
for others.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/rustllvm/RustWrapper.cpp b/src/rustllvm/RustWrapper.cpp
index 16d08ee534e..e6c45b8e362 100644
--- a/src/rustllvm/RustWrapper.cpp
+++ b/src/rustllvm/RustWrapper.cpp
@@ -87,6 +87,14 @@ extern "C" char *LLVMRustGetLastError(void) {
   return Ret;
 }
 
+extern "C" unsigned int LLVMRustGetInstructionCount(LLVMModuleRef M) {
+#if LLVM_VERSION_GE(7, 0)
+  return unwrap(M)->getInstructionCount();
+#else
+  report_fatal_error("Module::getInstructionCount not available before LLVM 7");
+#endif
+}
+
 extern "C" void LLVMRustSetLastError(const char *Err) {
   free((void *)LastError);
   LastError = strdup(Err);