crypto: x86/sha256-ni - rename some register aliases

MSGTMP[0-3] are used to hold the message schedule and are not temporary
registers per se.  MSGTMP4 is used as a temporary register for several
different purposes and isn't really related to MSGTMP[0-3].  Rename them
to MSG[0-3] and TMP accordingly.

Also add a comment that clarifies what MSG is.

Suggested-by: Stefan Kanthak <stefan.kanthak@nexgo.de>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/arch/x86/crypto/sha256_ni_asm.S b/arch/x86/crypto/sha256_ni_asm.S
index 498f67727b94c91ee81c349c84ce0e3a00642a46..b7e7001dafdfd75b4e54c22b1e365c641c74ec3d 100644 (file)
--- a/arch/x86/crypto/sha256_ni_asm.S
+++ b/arch/x86/crypto/sha256_ni_asm.S
@@ -62,14 +62,14 @@
 
 #define SHA256CONSTANTS        %rax
 
-#define MSG            %xmm0
+#define MSG            %xmm0  /* sha256rnds2 implicit operand */
 #define STATE0         %xmm1
 #define STATE1         %xmm2
-#define MSGTMP0                %xmm3
-#define MSGTMP1                %xmm4
-#define MSGTMP2                %xmm5
-#define MSGTMP3                %xmm6
-#define MSGTMP4                %xmm7
+#define MSG0           %xmm3
+#define MSG1           %xmm4
+#define MSG2           %xmm5
+#define MSG3           %xmm6
+#define TMP            %xmm7
 
 #define SHUF_MASK      %xmm8
 
@@ -87,9 +87,9 @@
        paddd           \i*4(SHA256CONSTANTS), MSG
        sha256rnds2     STATE0, STATE1
 .if \i >= 12 && \i < 60
-       movdqa          \m0, MSGTMP4
-       palignr         $4, \m3, MSGTMP4
-       paddd           MSGTMP4, \m1
+       movdqa          \m0, TMP
+       palignr         $4, \m3, TMP
+       paddd           TMP, \m1
        sha256msg2      \m0, \m1
 .endif
        pshufd          $0x0E, MSG, MSG
@@ -133,9 +133,9 @@ SYM_TYPED_FUNC_START(sha256_ni_transform)
 
        pshufd          $0xB1, STATE0,  STATE0          /* CDAB */
        pshufd          $0x1B, STATE1,  STATE1          /* EFGH */
-       movdqa          STATE0, MSGTMP4
+       movdqa          STATE0, TMP
        palignr         $8, STATE1,  STATE0             /* ABEF */
-       pblendw         $0xF0, MSGTMP4, STATE1          /* CDGH */
+       pblendw         $0xF0, TMP, STATE1              /* CDGH */
 
        movdqa          PSHUFFLE_BYTE_FLIP_MASK(%rip), SHUF_MASK
        lea             K256(%rip), SHA256CONSTANTS
@@ -146,10 +146,10 @@ SYM_TYPED_FUNC_START(sha256_ni_transform)
        movdqa          STATE1, CDGH_SAVE
 
 .irp i, 0, 16, 32, 48
-       do_4rounds      (\i + 0),  MSGTMP0, MSGTMP1, MSGTMP2, MSGTMP3
-       do_4rounds      (\i + 4),  MSGTMP1, MSGTMP2, MSGTMP3, MSGTMP0
-       do_4rounds      (\i + 8),  MSGTMP2, MSGTMP3, MSGTMP0, MSGTMP1
-       do_4rounds      (\i + 12), MSGTMP3, MSGTMP0, MSGTMP1, MSGTMP2
+       do_4rounds      (\i + 0),  MSG0, MSG1, MSG2, MSG3
+       do_4rounds      (\i + 4),  MSG1, MSG2, MSG3, MSG0
+       do_4rounds      (\i + 8),  MSG2, MSG3, MSG0, MSG1
+       do_4rounds      (\i + 12), MSG3, MSG0, MSG1, MSG2
 .endr
 
        /* Add current hash values with previously saved */
@@ -164,9 +164,9 @@ SYM_TYPED_FUNC_START(sha256_ni_transform)
        /* Write hash values back in the correct order */
        pshufd          $0x1B, STATE0,  STATE0          /* FEBA */
        pshufd          $0xB1, STATE1,  STATE1          /* DCHG */
-       movdqa          STATE0, MSGTMP4
+       movdqa          STATE0, TMP
        pblendw         $0xF0, STATE1,  STATE0          /* DCBA */
-       palignr         $8, MSGTMP4, STATE1             /* HGFE */
+       palignr         $8, TMP, STATE1                 /* HGFE */
 
        movdqu          STATE0, 0*16(DIGEST_PTR)
        movdqu          STATE1, 1*16(DIGEST_PTR)