bn/asm/rsaz-avx2.pl: refine Win64 SE handler.

Reviewed-by: Rich Salz <rsalz@openssl.org>

diff --git a/crypto/bn/asm/rsaz-avx2.pl b/crypto/bn/asm/rsaz-avx2.pl
index e620285e61b2ab8e1a7b4f6027a58a8cc7d32b05..6d23fefd2cea9048d268eea126816e3e53f32bcc 100755 (executable)
--- a/crypto/bn/asm/rsaz-avx2.pl
+++ b/crypto/bn/asm/rsaz-avx2.pl
@@ -827,6 +827,7 @@ $code.=<<___;
        mov     %rbp, %rax
 ___
 $code.=<<___ if ($win64);
+.Lsqr_1024_in_tail:
        movaps  -0xd8(%rax),%xmm6
        movaps  -0xc8(%rax),%xmm7
        movaps  -0xb8(%rax),%xmm8
@@ -1460,6 +1461,7 @@ $code.=<<___;
        mov     %rbp, %rax
 ___
 $code.=<<___ if ($win64);
+.Lmul_1024_in_tail:
        movaps  -0xd8(%rax),%xmm6
        movaps  -0xc8(%rax),%xmm7
        movaps  -0xb8(%rax),%xmm8
@@ -1815,14 +1817,17 @@ rsaz_se_handler:
        cmp     %r10,%rbx               # context->Rip<prologue label
        jb      .Lcommon_seh_tail
 
-       mov     152($context),%rax      # pull context->Rsp
-
        mov     4(%r11),%r10d           # HandlerData[1]
        lea     (%rsi,%r10),%r10        # epilogue label
        cmp     %r10,%rbx               # context->Rip>=epilogue label
        jae     .Lcommon_seh_tail
 
-       mov     160($context),%rax      # pull context->Rbp
+       mov     160($context),%rbp      # pull context->Rbp
+
+       mov     8(%r11),%r10d           # HandlerData[2]
+       lea     (%rsi,%r10),%r10        # "in tail" label
+       cmp     %r10,%rbx               # context->Rip>="in tail" label
+       cmovc   %rbp,%rax
 
        mov     -48(%rax),%r15
        mov     -40(%rax),%r14
@@ -1900,11 +1905,13 @@ rsaz_se_handler:
 .LSEH_info_rsaz_1024_sqr_avx2:
        .byte   9,0,0,0
        .rva    rsaz_se_handler
-       .rva    .Lsqr_1024_body,.Lsqr_1024_epilogue
+       .rva    .Lsqr_1024_body,.Lsqr_1024_epilogue,.Lsqr_1024_in_tail
+       .long   0
 .LSEH_info_rsaz_1024_mul_avx2:
        .byte   9,0,0,0
        .rva    rsaz_se_handler
-       .rva    .Lmul_1024_body,.Lmul_1024_epilogue
+       .rva    .Lmul_1024_body,.Lmul_1024_epilogue,.Lmul_1024_in_tail
+       .long   0
 .LSEH_info_rsaz_1024_gather5:
        .byte   0x01,0x36,0x17,0x0b
        .byte   0x36,0xf8,0x09,0x00     # vmovaps 0x90(rsp),xmm15