diff options
| author | Arjan van de Ven <arjan@linux.intel.com> | 2006-07-27 23:12:08 +0000 |
|---|---|---|
| committer | Christopher Faylor <cgf@gcc.gnu.org> | 2006-07-27 23:12:08 +0000 |
| commit | fa6adcab9d8c2ff6be87e30fb663ede9a664b9ff (patch) | |
| tree | 8a8ae5d5601b225f6c7d6129e61fd25a2b15f49f /gcc/config | |
| parent | ab7efd9148063d4bcb27ae72dd390b1c5fc18a58 (diff) | |
| download | gcc-fa6adcab9d8c2ff6be87e30fb663ede9a664b9ff.tar.gz | |
2006-07-27 Arjan van de Ven <arjan@linux.intel.com>
* config/i386/i386.md (stack_tls_protect_set_di) Use %gs rather than
%fs for -mcmodel=kernel.
(stack_tls_protect_test_di): Likewise.
* testsuite/gcc.target/i386/stack-prot-kernel.c: New test.
From-SVN: r115782
Diffstat (limited to 'gcc/config')
| -rw-r--r-- | gcc/config/i386/i386.md | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index 00e06ba7e77..4808853e655 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -20393,7 +20393,15 @@ (set (match_scratch:DI 2 "=&r") (const_int 0)) (clobber (reg:CC FLAGS_REG))] "TARGET_64BIT" - "mov{q}\t{%%fs:%P1, %2|%2, QWORD PTR %%fs:%P1}\;mov{q}\t{%2, %0|%0, %2}\;xor{l}\t%k2, %k2" + { + /* The kernel uses a different segment register for performance reasons; a + system call would not have to trash the userspace segment register, + which would be expensive */ + if (ix86_cmodel != CM_KERNEL) + return "mov{q}\t{%%fs:%P1, %2|%2, QWORD PTR %%fs:%P1}\;mov{q}\t{%2, %0|%0, %2}\;xor{l}\t%k2, %k2"; + else + return "mov{q}\t{%%gs:%P1, %2|%2, QWORD PTR %%gs:%P1}\;mov{q}\t{%2, %0|%0, %2}\;xor{l}\t%k2, %k2"; + } [(set_attr "type" "multi")]) (define_expand "stack_protect_test" @@ -20461,7 +20469,15 @@ UNSPEC_SP_TLS_TEST)) (clobber (match_scratch:DI 3 "=r"))] "TARGET_64BIT" - "mov{q}\t{%1, %3|%3, %1}\;xor{q}\t{%%fs:%P2, %3|%3, QWORD PTR %%fs:%P2}" + { + /* The kernel uses a different segment register for performance reasons; a + system call would not have to trash the userspace segment register, + which would be expensive */ + if (ix86_cmodel != CM_KERNEL) + return "mov{q}\t{%1, %3|%3, %1}\;xor{q}\t{%%fs:%P2, %3|%3, QWORD PTR %%fs:%P2}"; + else + return "mov{q}\t{%1, %3|%3, %1}\;xor{q}\t{%%gs:%P2, %3|%3, QWORD PTR %%gs:%P2}"; + } [(set_attr "type" "multi")]) (include "sse.md") |