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[RS6000] strict alignment for little-endian
- From: Alan Modra <amodra at gmail dot com>
- To: gcc at gcc dot gnu dot org
- Cc: David Edelsohn <dje dot gcc at gmail dot com>, Michael Meissner <mrmeissn at us dot ibm dot com>
- Date: Fri, 7 Jun 2013 10:54:39 +0930
- Subject: [RS6000] strict alignment for little-endian
I'd like to remove -mstrict-align for little-endian powerpc, because
the assumption that mis-aligned accesses are massively slow isn't true
for current powerpc processors. However I also don't want to break
old machines, so probably should add -mstrict-align back for some set
of cpus. Can anyone tell me the set?
Index: gcc/config/rs6000/sysv4.h
===================================================================
--- gcc/config/rs6000/sysv4.h (revision 199718)
+++ gcc/config/rs6000/sysv4.h (working copy)
@@ -538,12 +538,7 @@
#define CC1_ENDIAN_BIG_SPEC ""
-#define CC1_ENDIAN_LITTLE_SPEC "\
-%{!mstrict-align: %{!mno-strict-align: \
- %{!mcall-i960-old: \
- -mstrict-align \
- } \
-}}"
+#define CC1_ENDIAN_LITTLE_SPEC ""
#define CC1_ENDIAN_DEFAULT_SPEC "%(cc1_endian_big)"
--
Alan Modra
Australia Development Lab, IBM