RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

checkasm: x86: properly save rdx/edx in checked_call() 

If the return value doesn't fit in a single register rdx/edx can in some
cases be used in addition to rax/eax.

Doesn't affect any of the existing checkasm tests but might be useful later.

Also comment the relevant code a bit better.
This commit is contained in:
Henrik Gramner 2015-08-16 17:09:40 +02:00
parent 18b101ff59
commit e6b8797b82
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
tests/checkasm/x86/checkasm.asm
View File

@ -145,10 +145,15 @@ cglobal checked_call, 2,15,16,max_args*8+8
or r14, r5 or r14, r5
%endif %endif
; Call fail_func() with a descriptive message to mark it as a failure
; if the called function didn't preserve all callee-saved registers.
; Save the return value located in rdx:rax first to prevent clobbering.
jz .ok jz .ok
mov r9, rax mov r9, rax
mov r10, rdx
lea r0, [error_message] lea r0, [error_message]
call fail_func call fail_func
mov rdx, r10
mov rax, r9 mov rax, r9
.ok: .ok:
RET RET
@ -182,9 +187,11 @@ cglobal checked_call, 1,7
or r3, r5 or r3, r5
jz .ok jz .ok
mov r3, eax mov r3, eax
mov r4, edx
lea r0, [error_message] lea r0, [error_message]
mov [esp], r0 mov [esp], r0
call fail_func call fail_func
mov edx, r4
mov eax, r3 mov eax, r3
.ok: .ok:
add esp, max_args*4 add esp, max_args*4