[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-12-22 11:27 --- Introduced with: 2004-12-19 Richard Henderson [EMAIL PROTECTED] * config/i386/i386.c (ix86_hard_regno_mode_ok): Always accept all SSE, MMX, 3DNOW modes in SSE registers; always accept all MMX, 3DNOW modes in MMX registers. * config/i386/i386.h (VALID_SSE2_REG_MODE): Don't include VALID_MMX_REG_MODE. * config/i386/i386.md (movv4sf_internal, movv4si_internal, movv2di_internal, movv2si_internal, movv4hi_internal, movv2sf_internal, movv2df_internal, movv8hi_internal, movv16qi_internal, movti_internal): Add leading '*' to name. (movv2di_internal, movv2df_internal, movv8hi_internal, movv16qi_internal, movv2df, movv8hi, movv16qi, movv2di, pushv2di, pushv8hi, pushv16qi): Enable for SSE1. (movv2si_internal, movv4hi_internal): Add SSE alternatives. (movv8qi_internal, movv2sf_internal): Likewise. (movtf): Simplify conditional. (movv2sf, pushv2sf): Enable for MMX. -- What|Removed |Added Last reconfirmed|2004-12-21 12:22:41 |2004-12-22 11:27:44 date|| http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-12-22 11:43 --- Investigating. -- What|Removed |Added AssignedTo|unassigned at gcc dot gnu |ebotcazou at gcc dot gnu dot |dot org |org Status|NEW |ASSIGNED http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-12-22
12:24 ---
Why do we allow MMX modes in SSE regs now? The following patchlet is sufficient
to fix the problem:
Index: config/i386/i386.c
===
RCS file: /cvs/gcc/gcc/gcc/config/i386/i386.c,v
retrieving revision 1.635.2.18
diff -u -p -r1.635.2.18 i386.c
--- config/i386/i386.c 20 Dec 2004 05:37:36 - 1.635.2.18
+++ config/i386/i386.c 22 Dec 2004 12:21:42 -
@@ -14931,9 +14931,7 @@ ix86_hard_regno_mode_ok (int regno, enum
out of SSE registers, even when no operation instructions
are available. */
return (VALID_SSE_REG_MODE (mode)
- || VALID_SSE2_REG_MODE (mode)
- || VALID_MMX_REG_MODE (mode)
- || VALID_MMX_REG_MODE_3DNOW (mode));
+ || VALID_SSE2_REG_MODE (mode));
}
if (MMX_REGNO_P (regno))
{
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-12-22 18:49 --- I can't do much more at this point. -- What|Removed |Added CC||ebotcazou at gcc dot gnu dot ||org AssignedTo|ebotcazou at gcc dot gnu dot|unassigned at gcc dot gnu |org |dot org Status|ASSIGNED|NEW http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From rth at gcc dot gnu dot org 2004-12-22 19:12 --- Subject: Re: [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20 Why do we allow MMX modes in SSE regs now? Because x86-64 calling conventions demand it. r~ -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-12-22 20:24 --- Why do we allow MMX modes in SSE regs now? Because x86-64 calling conventions demand it. The calling conventions for vector types I presume? The problem is that SImode slipped through the cracks so the register allocator now jumps from SIREG to INT_SSE_REGS for SImode pseudos. Is that an unintended side-effect? -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
-- What|Removed |Added Severity|critical|normal http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-12-22 23:18 --- And, actually, we allowed MMX modes with -msse2 before, so there must be another explanation of why things wouldn't have been failing with -march=pentium4. Allocation ordering considerations? -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From rth at gcc dot gnu dot org 2004-12-22 23:27 --- Apparently register move costs. Testing a Large Hack to prevent this suddenly appearing on the 3.4 branch. For mainline, move pattern constraints should be fixed, and folks will have to make sure to use -mno-sse when sse is not desired. Plus, -mno-sse will have to be fixed such that it's effective when -march implies sse[23], and we'll have to add extra code to not ICE on x86-64 when the ABI specifies that parameters go in disabled registers. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From ak at muc dot de 2004-12-22 23:53 --- FWIW i compiled a full 3.3-hammer compiled 2.6.10rc3 x86-64 kernel for suspicious use of %xmm or %mm and there wasn't any. There also is a warning in all 2.6 x86-64 kernels for kernel FPU use at runtime. So at least on x86-64 it doesn't seem to be a real issue in practice. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From cvs-commit at gcc dot gnu dot org 2004-12-23 01:31 --- Subject: Bug 19102 CVSROOT:/cvs/gcc Module name:gcc Branch: gcc-3_4-branch Changes by: [EMAIL PROTECTED] 2004-12-23 01:31:20 Modified files: gcc: ChangeLog gcc/config/i386: i386.c Log message: PR target/19102 * config/i386/i386.c (x86_inter_unit_moves): Disable. (ix86_hard_regno_mode_ok): Disallow SSE2 and MMX scalar modes in SSE registers when only SSE1 enabled. Patches: http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcconly_with_tag=gcc-3_4-branchr1=2.2326.2.750r2=2.2326.2.751 http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/i386/i386.c.diff?cvsroot=gcconly_with_tag=gcc-3_4-branchr1=1.635.2.18r2=1.635.2.19 -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From rth at gcc dot gnu dot org 2004-12-23 01:40 --- http://gcc.gnu.org/ml/gcc-patches/2004-12/msg01777.html -- What|Removed |Added Status|ASSIGNED|RESOLVED Resolution||FIXED http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From belyshev at lubercy dot com 2004-12-21 12:22
---
/* reduced testcase, use -O1 -march=pentium3 */
int unknown_bootoption (void)
{
int i, j, k, l;
for (i = 0; i 2; i++)
asm volatile(
:=a (j), =S (k), =c (l)
:1 (0), 2 (0));
return 0;
}
--
What|Removed |Added
CC||rth at gcc dot gnu dot org
Severity|normal |critical
Status|UNCONFIRMED |NEW
Component|c |target
Ever Confirmed||1
GCC build triplet|i686-ark-linux |
GCC host triplet|i686-ark-linux |
GCC target triplet|i686-ark-linux |i686-*-*
Keywords||ice-on-valid-code
Last reconfirmed|-00-00 00:00:00 |2004-12-21 12:22:41
date||
Summary|-march=pentium3 breaks linux|[3.4 Regression] -
|kernel compiles w/ gcc-3_4- |march=pentium3 breaks linux
|branch as of 2004/12/20 |kernel compiles w/ gcc-3_4-
||branch as of 2004/12/20
Target Milestone|--- |3.4.4
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From pinskia at gcc dot gnu dot org 2004-12-21 16:44 --- Hmm, it worked with 2004-12-11. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From bero at arklinux dot org 2004-12-21 17:55 --- Worked in 2004-12-17 too, broken in 2004-12-20 and 2004-12-21 (I don't have -18 and -19) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
[Bug target/19102] [3.4 Regression] -march=pentium3 breaks linux kernel compiles w/ gcc-3_4-branch as of 2004/12/20
--- Additional Comments From bero at arklinux dot org 2004-12-21 18:00 --- Must be a cc1 issue - 2004-12-21 with 2004-12-17's /usr/libexec/gcc/*/3.4.4/cc1 works -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19102
