Hello.
I accidentally learned that -fipa-ra option is disabled if:
/* Do not use IPA optimizations for register allocation if profiler is active
or port does not emit prologue and epilogue as RTL. */
if (profile_flag || !targetm.have_prologue () || !targetm.have_epilogue ())
flag_ipa_ra = 0;
So I basically copied the comment to invoke.texi.
Apart from that, I've noticed that '-fprofile' (which is alias of '-p') is not
documented.
Shouldn't it be documented as an alias?
Thanks,
Martin
>From e43eb357b986234e0454e6f6898ef5ae46a7a596 Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Wed, 13 Jul 2016 18:25:09 +0200
Subject: [PATCH] Enhance documentation of -fipa-ra option.
gcc/ChangeLog:
2016-07-13 Martin Liska <mli...@suse.cz>
* doc/invoke.texi (-fipa-ra): Document when the option is
disabled. Fix a typo.
---
gcc/doc/invoke.texi | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 9a4db38..647caae 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -7260,7 +7260,9 @@ any called function. In that case it is not necessary to save and restore
them around calls. This is only possible if called functions are part of
same compilation unit as current function and they are compiled before it.
-Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}.
+Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}, however the option
+is disabled if profiler is active (@option{-p}, @option{-pg} or
+@option{-fprofile}) or a port does not emit prologue and epilogue as RTL.
@item -fconserve-stack
@opindex fconserve-stack
@@ -7280,7 +7282,7 @@ Perform code hoisting. Code hoisting tries to move the
evaluation of expressions executed on all paths to the function exit
as early as possible. This is especially useful as a code size
optimization, but it often helps for code speed as well.
-This flag is enabled by defailt at @option{-O2} and higher.
+This flag is enabled by default at @option{-O2} and higher.
@item -ftree-pre
@opindex ftree-pre
--
2.8.4
