* [PATCH, i386]: Do not check index when encoding %esp as %rsp to avoid 0x67 prefix
@ 2017-09-28 18:16 Uros Bizjak
0 siblings, 0 replies; only message in thread
From: Uros Bizjak @ 2017-09-28 18:16 UTC (permalink / raw)
To: gcc-patches
[-- Attachment #1: Type: text/plain, Size: 337 bytes --]
As mentioned in the PR, SP_REG can not be encoded as index.
2017-09-28 Uros Bizjak <ubizjak@gmail.com>
* config/i386/i386.c (ix86_print_operand_address_as): Do not check
index when encoding %esp as %rsp to avoid 0x67 prefix.
Bootstrapped and regression tested on x86_64-linux-gnu {,-m32}.
Committed to mainline SVN.
Uros.
[-- Attachment #2: p.diff.txt --]
[-- Type: text/plain, Size: 877 bytes --]
Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c (revision 253254)
+++ config/i386/i386.c (working copy)
@@ -19953,12 +19953,11 @@ ix86_print_operand_address_as (FILE *file, rtx add
code = 'k';
}
- /* Since the upper 32 bits of RSP are always zero for x32, we can
- encode %esp as %rsp to avoid 0x67 prefix if there is no index or
- base register. */
+ /* Since the upper 32 bits of RSP are always zero for x32,
+ we can encode %esp as %rsp to avoid 0x67 prefix if
+ there is no index register. */
if (TARGET_X32 && Pmode == SImode
- && ((!index && base && REG_P (base) && REGNO (base) == SP_REG)
- || (!base && index && REGNO (index) == SP_REG)))
+ && !index && base && REG_P (base) && REGNO (base) == SP_REG)
code = 'q';
if (ASSEMBLER_DIALECT == ASM_ATT)
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2017-09-28 18:16 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-09-28 18:16 [PATCH, i386]: Do not check index when encoding %esp as %rsp to avoid 0x67 prefix Uros Bizjak
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).