Revert r97185 "Update libvpx snapshot to v0.9.7-p1 (Cayuga)."

libvpx/source/libvpx/vpx_ports/x86_abi_support.asm

Index: libvpx/source/libvpx/vpx_ports/x86_abi_support.asm
diff --git a/libvpx/source/libvpx/vpx_ports/x86_abi_support.asm b/libvpx/source/libvpx/vpx_ports/x86_abi_support.asm
index 7382a913454916c4d00b127e1eb60b4df2550e7b..be64cd7c708020a09a726a655c4b8e86e77efb75 100644
--- a/libvpx/source/libvpx/vpx_ports/x86_abi_support.asm
+++ b/libvpx/source/libvpx/vpx_ports/x86_abi_support.asm
@@ -147,7 +147,6 @@
 %if ABI_IS_32BIT
   %if CONFIG_PIC=1
   %ifidn __OUTPUT_FORMAT__,elf32
-    %define GET_GOT_SAVE_ARG 1
     %define WRT_PLT wrt ..plt
     %macro GET_GOT 1
       extern _GLOBAL_OFFSET_TABLE_
@@ -166,7 +165,6 @@
       %define RESTORE_GOT pop %1
     %endmacro
   %elifidn __OUTPUT_FORMAT__,macho32
-    %define GET_GOT_SAVE_ARG 1
     %macro GET_GOT 1
       push %1
       call %%get_got
@@ -257,48 +255,21 @@
   %define UNSHADOW_ARGS mov rsp, rbp
 %endif
 
-; Win64 ABI requires that XMM6:XMM15 are callee saved
-; SAVE_XMM n, [u]
-; store registers 6-n on the stack
-; if u is specified, use unaligned movs.
-; Win64 ABI requires 16 byte stack alignment, but then pushes an 8 byte return
-; value. Typically we follow this up with 'push rbp' - re-aligning the stack -
-; but in some cases this is not done and unaligned movs must be used.
+; must keep XMM6:XMM15 (libvpx uses XMM6 and XMM7) on Win64 ABI
+; rsp register has to be aligned
 %ifidn __OUTPUT_FORMAT__,x64
-%macro SAVE_XMM 1-2 a
-  %if %1 < 6
-    %error Only xmm registers 6-15 must be preserved
-  %else
-    %assign last_xmm %1
-    %define movxmm movdq %+ %2
-    %assign xmm_stack_space ((last_xmm - 5) * 16)
-    sub rsp, xmm_stack_space
-    %assign i 6
-    %rep (last_xmm - 5)
-      movxmm [rsp + ((i - 6) * 16)], xmm %+ i
-      %assign i i+1
-    %endrep
-  %endif
+%macro SAVE_XMM 0
+  sub rsp, 32
+  movdqa XMMWORD PTR [rsp], xmm6
+  movdqa XMMWORD PTR [rsp+16], xmm7
 %endmacro
 %macro RESTORE_XMM 0
-  %ifndef last_xmm
-    %error RESTORE_XMM must be paired with SAVE_XMM n
-  %else
-    %assign i last_xmm
-    %rep (last_xmm - 5)
-      movxmm xmm %+ i, [rsp +((i - 6) * 16)]
-      %assign i i-1
-    %endrep
-    add rsp, xmm_stack_space
-    ; there are a couple functions which return from multiple places.
-    ; otherwise, we could uncomment these:
-    ; %undef last_xmm
-    ; %undef xmm_stack_space
-    ; %undef movxmm
-  %endif
+  movdqa xmm6, XMMWORD PTR [rsp]
+  movdqa xmm7, XMMWORD PTR [rsp+16]
+  add rsp, 32
 %endmacro
 %else
-%macro SAVE_XMM 1-2
+%macro SAVE_XMM 0
 %endmacro
 %macro RESTORE_XMM 0
 %endmacro