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linux-user: Fix i386 safe-syscall.S

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Clang insists that "cmp" is ambiguous with a memory destination,
requiring an explicit size suffix.

There was a true error in the use of .cfi_def_cfa_offset in the
epilogue, but changing to use the proper .cfi_adjust_cfa_offset
runs afoul of a clang bug wrt .cfi_restore_state.  Better to
fold the two epilogues so that we don't trigger the bug.

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2016-07-07 21:39:22 -07:00
parent 4f4a9ca4a4
commit 4aa3f4dd5b
1 changed files with 6 additions and 18 deletions
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24
linux-user/host/i386/safe-syscall.inc.S
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@ -69,7 +69,7 @@ safe_syscall_base:
safe_syscall_start: safe_syscall_start:
/* if signal_pending is non-zero, don't do the call */ /* if signal_pending is non-zero, don't do the call */
mov 4+16(%esp), %eax /* signal_pending */ mov 4+16(%esp), %eax /* signal_pending */
cmp $0, (%eax) cmpl $0, (%eax)
jnz 1f jnz 1f
mov 8+16(%esp), %eax /* syscall number */ mov 8+16(%esp), %eax /* syscall number */
int $0x80 int $0x80
@ -77,16 +77,16 @@ safe_syscall_end:
/* code path for having successfully executed the syscall */ /* code path for having successfully executed the syscall */
pop %ebx pop %ebx
.cfi_remember_state .cfi_remember_state
.cfi_def_cfa_offset -4 .cfi_adjust_cfa_offset -4
.cfi_restore ebx .cfi_restore ebx
pop %edi pop %edi
.cfi_def_cfa_offset -4 .cfi_adjust_cfa_offset -4
.cfi_restore edi .cfi_restore edi
pop %esi pop %esi
.cfi_def_cfa_offset -4 .cfi_adjust_cfa_offset -4
.cfi_restore esi .cfi_restore esi
pop %ebp pop %ebp
.cfi_def_cfa_offset -4 .cfi_adjust_cfa_offset -4
.cfi_restore ebp .cfi_restore ebp
ret ret
@ -94,19 +94,7 @@ safe_syscall_end:
/* code path when we didn't execute the syscall */ /* code path when we didn't execute the syscall */
.cfi_restore_state .cfi_restore_state
mov $-TARGET_ERESTARTSYS, %eax mov $-TARGET_ERESTARTSYS, %eax
pop %ebx jmp safe_syscall_end
.cfi_def_cfa_offset -4
.cfi_restore ebx
pop %edi
.cfi_def_cfa_offset -4
.cfi_restore edi
pop %esi
.cfi_def_cfa_offset -4
.cfi_restore esi
pop %ebp
.cfi_def_cfa_offset -4
.cfi_restore ebp
ret
.cfi_endproc .cfi_endproc
.size safe_syscall_base, .-safe_syscall_base .size safe_syscall_base, .-safe_syscall_base