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| author | Ulrich Drepper <drepper@redhat.com> | 2009-08-07 20:36:53 -0700 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2009-08-07 20:36:53 -0700 |
| commit | 9083bcc5dc747eeec24c2bb8bf5b7055b3bd4dbf (patch) | |
| tree | e5078f60592dcf86fcd638a7db7a5fa530ec668e /nptl/sysdeps/unix/sysv/linux/x86_64/sem_wait.S | |
| parent | 57b378ac895c346d74758b54f9e388ed3ca30751 (diff) | |
| download | glibc-9083bcc5dc747eeec24c2bb8bf5b7055b3bd4dbf.tar glibc-9083bcc5dc747eeec24c2bb8bf5b7055b3bd4dbf.tar.gz glibc-9083bcc5dc747eeec24c2bb8bf5b7055b3bd4dbf.tar.bz2 glibc-9083bcc5dc747eeec24c2bb8bf5b7055b3bd4dbf.zip | |
Small optimizations to cancellable x86-64 code.
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/x86_64/sem_wait.S')
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/x86_64/sem_wait.S | 58 |
1 files changed, 24 insertions, 34 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/sem_wait.S b/nptl/sysdeps/unix/sysv/linux/x86_64/sem_wait.S index a01d745a17..2cf6ec10a4 100644 --- a/nptl/sysdeps/unix/sysv/linux/x86_64/sem_wait.S +++ b/nptl/sysdeps/unix/sysv/linux/x86_64/sem_wait.S @@ -61,16 +61,13 @@ sem_wait: xorl %eax, %eax retq -1: pushq %r12 + /* This push is only needed to store the sem_t pointer for the + exception handler. */ +1: pushq %rdi cfi_adjust_cfa_offset(8) - cfi_rel_offset(%r12, 0) - pushq %r13 - cfi_adjust_cfa_offset(8) - cfi_rel_offset(%r13, 0) - movq %rdi, %r13 LOCK - addq $1, NWAITERS(%r13) + addq $1, NWAITERS(%rdi) .LcleanupSTART: 6: call __pthread_enable_asynccancel @@ -78,7 +75,6 @@ sem_wait: xorq %r10, %r10 movl $SYS_futex, %eax - movq %r13, %rdi #if FUTEX_WAIT == 0 movl PRIVATE(%rdi), %esi #else @@ -87,22 +83,23 @@ sem_wait: #endif xorl %edx, %edx syscall - movq %rax, %r12 + movq %rax, %rcx - movl %r8d, %edi + xchgq %r8, %rdi call __pthread_disable_asynccancel .LcleanupEND: + movq %r8, %rdi - testq %r12, %r12 + testq %rcx, %rcx je 3f - cmpq $-EWOULDBLOCK, %r12 + cmpq $-EWOULDBLOCK, %rcx jne 4f 3: #if VALUE == 0 - movl (%r13), %eax + movl (%rdi), %eax #else - movl VALUE(%r13), %eax + movl VALUE(%rdi), %eax #endif 5: testl %eax, %eax je 6b @@ -110,50 +107,43 @@ sem_wait: leal -1(%rax), %edx LOCK #if VALUE == 0 - cmpxchgl %edx, (%r13) + cmpxchgl %edx, (%rdi) #else - cmpxchgl %edx, VALUE(%r13) + cmpxchgl %edx, VALUE(%rdi) #endif jne 5b - LOCK - subq $1, NWAITERS(%r13) - xorl %eax, %eax -9: popq %r13 - cfi_adjust_cfa_offset(-8) - cfi_restore(%r13) - popq %r12 +9: LOCK + subq $1, NWAITERS(%rdi) + + leaq 8(%rsp), %rsp cfi_adjust_cfa_offset(-8) - cfi_restore(%r12) retq - cfi_adjust_cfa_offset(2 * 8) - cfi_rel_offset(%r12, 8) - cfi_rel_offset(%r13, 0) -4: negq %r12 + cfi_adjust_cfa_offset(8) +4: negq %rcx #if USE___THREAD movq errno@gottpoff(%rip), %rdx - movl %r12d, %fs:(%rdx) + movl %ecx, %fs:(%rdx) #else +# error "not supported. %rcx and %rdi must be preserved" callq __errno_location@plt - movl %r12d, (%rax) + movl %ecx, (%rax) #endif orl $-1, %eax - LOCK - subq $1, NWAITERS(%r13) - jmp 9b .size sem_wait,.-sem_wait .type sem_wait_cleanup,@function sem_wait_cleanup: + movq (%rsp), %rdi LOCK - subq $1, NWAITERS(%r13) + subq $1, NWAITERS(%rdi) movq %rax, %rdi .LcallUR: call _Unwind_Resume@PLT |