From 1578e91079162f7ff008520487623968fc0db687 Mon Sep 17 00:00:00 2001
From: Michael Matz <matz@suse.de>
Date: Tue, 20 Oct 2009 16:07:21 +0000
Subject: [PATCH] * loop-invariant.c (create_new_invariant): Use different
magic number.
From-SVN: r153022
---
gcc/ChangeLog | 4 ++++
gcc/loop-invariant.c | 11 ++++++++++-
2 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2a3bda14241a..3dfa1bbbc07d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2009-10-20 Michael Matz <matz@suse.de>
+
+ * loop-invariant.c (create_new_invariant): Use different magic number.
+
2009-10-20 Richard Earnshaw <rearnsha@arm.com>
PR target/39247
diff --git a/gcc/loop-invariant.c b/gcc/loop-invariant.c
index 8cbfdb30a922..901ce51ac89c 100644
--- a/gcc/loop-invariant.c
+++ b/gcc/loop-invariant.c
@@ -705,8 +705,17 @@ create_new_invariant (struct def *def, rtx insn, bitmap depends_on,
if (def)
{
inv->cost = rtx_cost (set, SET, speed);
+ /* ??? Try to determine cheapness of address computation. Unfortunately
+ the address cost is only a relative measure, we can't really compare
+ it with any absolute number, but only with other address costs.
+ But here we don't have any other addresses, so compare with a magic
+ number anyway. It has to be large enough to not regress PR33928
+ (by avoiding to move reg+8,reg+16,reg+24 invariants), but small
+ enough to not regress 410.bwaves either (by still moving reg+reg
+ invariants).
+ See http://gcc.gnu.org/ml/gcc-patches/2009-10/msg01210.html . */
inv->cheap_address = address_cost (SET_SRC (set), word_mode,
- speed) < COSTS_N_INSNS (1);
+ speed) < 3;
}
else
{
--
GitLab