| Summary: | fails to build with march=all on arm | ||
|---|---|---|---|
| Product: | binutils | Reporter: | Arnaud Patard <arnaud.patard> |
| Component: | gas | Assignee: | unassigned |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | CC: | nickc, zhenqiang.chen |
| Priority: | P2 | ||
| Version: | unspecified | ||
| Target Milestone: | --- | ||
| Host: | Target: | ||
| Build: | Last reconfirmed: | ||
| Attachments: | failed case | ||
CVSROOT: /cvs/src Module name: src Changes by: nickc@sourceware.org 2011-06-03 14:42:48 Modified files: gas : ChangeLog gas/config : tc-arm.c Log message: PR gas/12698 * config/tc-arm.c (parse_psr): Set m_profile to false when assembling for any architecture. Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/src/gas/ChangeLog.diff?cvsroot=src&r1=1.4499&r2=1.4500 http://sourceware.org/cgi-bin/cvsweb.cgi/src/gas/config/tc-arm.c.diff?cvsroot=src&r1=1.490&r2=1.491 Hi Arnaud, Thanks for reporting this problem and providing a patch. Your solution works, so I have checked it in, with a slightly tweaked comment. Cheers Nick Created attachment 6435 [details]
failed case
Assembler fail.
The attached case is from kernel. We still get fail: head2.s: Assembler messages: head2.s:60: Error: selected processor does not support requested special purpose register -- `mrs r2,cpsr' head2.s:67: Error: selected processor does not support requested special purpose register -- `mrs r2,cpsr' head2.s:69: Error: selected processor does not support requested special purpose register -- `msr cpsr_c,r2' The fault occurs in 2.22 and current trunk. To reproduce it: arm-linux-gnueabi-as --gdwarf2 -EL -march=armv7-a -mfloat-abi=soft -mfpu=vfpv3-d16 -meabi=5 -mimplicit-it=always -mno-warn-deprecated -mthumb -march=all -o head.o head2.s Here is a reference patch based on your previous one.
Both function do_t_mrs and do_t_msr need update.
diff --git a/gas/config/tc-arm.c b/gas/config/tc-arm.c
index 6ff64a6..7f69ffa 100644
--- a/gas/config/tc-arm.c
+++ b/gas/config/tc-arm.c
@@ -11201,8 +11201,14 @@ do_t_mrs (void)
int flags = inst.operands[1].imm & (PSR_c|PSR_x|PSR_s|PSR_f|SPSR_BIT);
if (ARM_CPU_HAS_FEATURE (selected_cpu, arm_ext_m))
- constraint (flags != 0, _("selected processor does not support "
- "requested special purpose register"));
+ {
+ /* PR gas/12698: The constraint is only applied for m_profile.
+ If the user has specified -march=all, we want to ignore it as
+ we are building for any CPU type, including non-m variants. */
+ bfd_boolean m_profile = selected_cpu.core != arm_arch_any.core;
+ constraint ((flags != 0) && m_profile, _("selected processor does "
+ "not support requested special purpose register"));
+ }
else
/* mrs only accepts APSR/CPSR/SPSR/CPSR_all/SPSR_all (for non-M profile
devices). */
@@ -11235,11 +11241,14 @@ do_t_msr (void)
if (ARM_CPU_HAS_FEATURE (selected_cpu, arm_ext_m))
{
int bits = inst.operands[0].imm & (PSR_c|PSR_x|PSR_s|PSR_f|SPSR_BIT);
-
- constraint ((ARM_CPU_HAS_FEATURE (selected_cpu, arm_ext_v6_dsp)
+ /* PR gas/12698: The constraint is only applied for m_profile.
+ If the user has specified -march=all, we want to ignore it as
+ we are building for any CPU type, including non-m variants. */
+ bfd_boolean m_profile = selected_cpu.core != arm_arch_any.core;
+ constraint (((ARM_CPU_HAS_FEATURE (selected_cpu, arm_ext_v6_dsp)
&& (bits & ~(PSR_s | PSR_f)) != 0)
|| (!ARM_CPU_HAS_FEATURE (selected_cpu, arm_ext_v6_dsp)
- && bits != PSR_f),
+ && bits != PSR_f)) && m_profile,
_("selected processor does not support requested special "
"purpose register"));
}
CVSROOT: /cvs/src Module name: src Changes by: nickc@sourceware.org 2012-06-13 14:19:00 Modified files: gas : ChangeLog gas/config : tc-arm.c Log message: PR gas/12698 * config/tc-arm.c (do_t_mrs): Do not require an m-profile architecure when assembling for all archiectures. (do_t_msr): Likewise. Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/src/gas/ChangeLog.diff?cvsroot=src&r1=1.4752&r2=1.4753 http://sourceware.org/cgi-bin/cvsweb.cgi/src/gas/config/tc-arm.c.diff?cvsroot=src&r1=1.519&r2=1.520 Hi Chen, Thanks for the patch - I have applied it to the mainline sources. Cheers Nick |
As noticed by debian bug 623964, when building an arm kernel with a snasphot made on 04/19, compiling head.S is failing with : Error: selected processor does not support requested special purpose register -- `mrs r2,cpsr' It's valid for current head. To reproduce, create a head.S containing: mrs r2, cpsr msr cpsr_c, r2 And then build with ./gas/as-new -march=all -c head.S -o head.o I believe it's due to this commit : http://sourceware.org/git/?p=binutils.git;a=commitdiff;h=335cd49156302284cea0438fd068f0a7cc11355a I've written this workaround: --- binutils.orig/gas/config/tc-arm.c +++ binutils/gas/config/tc-arm.c @@ -5356,6 +5356,11 @@ parse_psr (char **str, bfd_boolean lhs) bfd_boolean is_apsr = FALSE; bfd_boolean m_profile = ARM_CPU_HAS_FEATURE (selected_cpu, arm_ext_m); + /* march=all, will match the m_profile case too, so things like 'mrs r2,cpsr' + * will now fail. Workaround by saying it's not a m profile */ + if (selected_cpu.core == arm_arch_any.core) + m_profile = FALSE; + /* CPSR's and SPSR's can now be lowercase. This is just a convenience feature for ease of use and backwards compatibility. */ p = *str; It doesn't seem to create any regression but I'm not sure how good is this patch. At least, I hope it'll help fixing the bug.