Win64: Don't emit unwind info for "leaf" functions (PR30337)
According to MSDN (see the PR), functions which don't touch any callee-saved
registers (including %rsp) don't need any unwind info.
This patch makes LLVM not emit unwind info for such functions, to save
binary size.
Differential Revision: https://reviews.llvm.org/D24748
llvm-svn: 282185
diff --git a/llvm/lib/CodeGen/AsmPrinter/WinException.cpp b/llvm/lib/CodeGen/AsmPrinter/WinException.cpp
index 8faf53f..72f8a21 100644
--- a/llvm/lib/CodeGen/AsmPrinter/WinException.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/WinException.cpp
@@ -90,7 +90,7 @@
// If we're not using CFI, we don't want the CFI or the personality, but we
// might want EH tables if we had EH pads.
- if (!Asm->MAI->usesWindowsCFI()) {
+ if (!Asm->MAI->usesWindowsCFI() || (!MF->hasWinCFI() && !Per)) {
shouldEmitLSDA = hasEHFunclets;
shouldEmitPersonality = false;
return;