From: Dirk Mueller <daywalker@users.sourceforge.net>
Date: Wed, 1 Oct 2003 10:19:08 +0000 (+0000)
Subject: speed optimisation: assuming that a tempreg not related to %esp before
X-Git-Tag: svn/VALGRIND_2_1_0~155
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=959360f151f69a2d86c0e549f9e69f2f9148bc64;p=thirdparty%2Fvalgrind.git

speed optimisation: assuming that a tempreg not related to %esp before
is PUTed into %ESP, we do *know* that this tempreg points to %ESP afterwards,
so track it.

reduces the amount of expensive "DO_GENERIC" calls by 75% in Khtml. I've
not observed a problem with it, but consider it experimental.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@1878
---

diff --git a/coregrind/vg_translate.c b/coregrind/vg_translate.c
index 390f436e74..cf6c9db074 100644
--- a/coregrind/vg_translate.c
+++ b/coregrind/vg_translate.c
@@ -1855,6 +1855,9 @@ UCodeBlock* vg_ESP_update_pass(UCodeBlock* cb_in)
          } else {
             /* Unknown delta */
             DO_GENERIC;
+            /* now we know the temp that points to %ESP */
+            if ( t_ESP == INVALID_TEMPREG )
+               t_ESP = u->val1;
          }
          delta = 0;