[PATCH] Fix PR rtl-optimization/108274

[Eric Botcazou via Gcc-patches]

Hi,

unlike other IPA passes, the ICF pass can be run at -O0 and some testcases 
rely on this in the testsuite.  Now it effectively creates a tail call so the 
DF information needs be updated in this case after epilogue creation.

Tested on x86-64/Linux, OK for mainline?


2023-01-13  Eric Botcazou  <ebotca...@adacore.com>

        PR rtl-optimization/108274
        * function.cc (thread_prologue_and_epilogue_insns): Also update the
        DF information for calls in a few more cases.

-- 
Eric Botcazou
diff --git a/gcc/function.cc b/gcc/function.cc
index d975b001ec9..95f47d287c5 100644
--- a/gcc/function.cc
+++ b/gcc/function.cc
@@ -6261,7 +6261,10 @@ thread_prologue_and_epilogue_insns (void)
 
   /* Threading the prologue and epilogue changes the artificial refs in the
      entry and exit blocks, and may invalidate DF info for tail calls.  */
-  if (optimize)
+  if (optimize
+      || flag_optimize_sibling_calls
+      || flag_ipa_icf_functions
+      || in_lto_p)
     df_update_entry_exit_and_calls ();
   else
     {