It is tested that EBX register is not preserved by IXAudio2VoiceCallback_OnVoiceProcessingPassStart callback in League of Legends. It doesn't lead to crash in the present xaudio, while it might still be a potential issue.
Details are in https://bugs.winehq.org/show_bug.cgi?id=46870, while that bug is not dedicated to this specific issue.
Signed-off-by: Paul Gofman gofmanp@gmail.com --- dlls/xaudio2_7/xaudio_dll.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/dlls/xaudio2_7/xaudio_dll.c b/dlls/xaudio2_7/xaudio_dll.c index 18306a1603..da34e480c1 100644 --- a/dlls/xaudio2_7/xaudio_dll.c +++ b/dlls/xaudio2_7/xaudio_dll.c @@ -41,7 +41,8 @@ WINE_DEFAULT_DEBUG_CHANNEL(xaudio2);
#if XAUDIO2_VER != 0 && defined(__i386__) -/* EVE Online uses an OnVoiceProcessingPassStart callback which corrupts %esi. */ +/* EVE Online uses an OnVoiceProcessingPassStart callback which corrupts %esi; + * League of Legends uses a callback which corrupts %ebx. */ #define IXAudio2VoiceCallback_OnVoiceProcessingPassStart(a, b) call_on_voice_processing_pass_start(a, b) extern void call_on_voice_processing_pass_start(IXAudio2VoiceCallback *This, UINT32 BytesRequired); __ASM_GLOBAL_FUNC( call_on_voice_processing_pass_start, @@ -54,13 +55,17 @@ __ASM_GLOBAL_FUNC( call_on_voice_processing_pass_start, __ASM_CFI(".cfi_rel_offset %esi,-4\n\t") "pushl %edi\n\t" __ASM_CFI(".cfi_rel_offset %edi,-8\n\t") + "pushl %ebx\n\t" + __ASM_CFI(".cfi_rel_offset %ebx,-12\n\t") "subl $8,%esp\n\t" "pushl 12(%ebp)\n\t" /* BytesRequired */ "pushl 8(%ebp)\n\t" /* This */ "movl 8(%ebp),%eax\n\t" "movl 0(%eax),%eax\n\t" "call *0(%eax)\n\t" /* This->lpVtbl->OnVoiceProcessingPassStart */ - "leal -8(%ebp),%esp\n\t" + "leal -12(%ebp),%esp\n\t" + "popl %ebx\n\t" + __ASM_CFI(".cfi_same_value %ebx\n\t") "popl %edi\n\t" __ASM_CFI(".cfi_same_value %edi\n\t") "popl %esi\n\t"