Use the straight-forward ROTATE macro.

I would hope any sensible compiler would recognize the rotation. (If
not, we should at least pull this into crypto/internal.h.) Confirmed
that clang at least produces the exact same instructions for
sha256_block_data_order for release + NO_ASM. This is also mostly moot
as SHA-1 and SHA-256 both have assembly versions on x86 that sidestep
most of this.

For the digests, take it out of md32_common.h since it doesn't use the
macro. md32_common.h isn't sure whether it's a multiply-included header
or not. It should be, but it has an #include guard (doesn't quite do
what you'd want) and will get HOST_c2l, etc., confused if one tries to
include it twice.

Change-Id: I1632801de6473ffd2c6557f3412521ec5d6b305c
Reviewed-on: https://boringssl-review.googlesource.com/6650
Reviewed-by: Adam Langley <agl@google.com>

crypto/des/internal.h

@@ -202,24 +202,7 @@ how to use xors :-) I got it to its final state.
 #define ITERATIONS 16
 #define HALF_ITERATIONS 8
 
-#if defined(_MSC_VER)
-#define ROTATE(a, n) (_lrotr(a, n))
-#elif defined(__ICC)
-#define ROTATE(a, n) (_rotr(a, n))
-#elif defined(__GNUC__) && __GNUC__ >= 2 && !defined(OPENSSL_NO_ASM) && \
-      !defined(__STRICT_ANSI__) && \
-      (defined(OPENSSL_X86) || defined(OPENSSL_X86_64))
-#define ROTATE(a, n)                                       \
-  ({                                                       \
-    unsigned int ret;                                      \
-    asm("rorl %1,%0" : "=r"(ret) : "I"(n), "0"(a) : "cc"); \
-    ret;                                                   \
-  })
-#endif
-
-#ifndef ROTATE
 #define ROTATE(a, n) (((a) >> (n)) + ((a) << (32 - (n))))
-#endif
 
 
 #if defined(__cplusplus)

crypto/digest/md32_common.h

@@ -140,27 +140,6 @@ extern "C" {
 #error "HASH_MAKE_STRING must be defined!"
 #endif
 
-#undef ROTATE
-#if defined(_MSC_VER)
-#define ROTATE(a, n) _lrotl(a, n)
-#elif defined(__ICC)
-#define ROTATE(a, n) _rotl(a, n)
-#elif defined(__GNUC__) && __GNUC__ >= 2 && !defined(OPENSSL_NO_ASM)
-#if defined(OPENSSL_X86) || defined(OPENSSL_X86_64)
-/* Note this macro requires |n| be a constant. */
-#define ROTATE(a, n)                                                    \
-  ({                                                                    \
-    register uint32_t ret;                                              \
-    asm("roll %1, %0" : "=r"(ret) : "I"(n), "0"((uint32_t)(a)) : "cc"); \
-    ret;                                                                \
-  })
-#endif /* OPENSSL_X86 || OPENSSL_X86_64 */
-#endif /* COMPILER */
-
-#ifndef ROTATE
-#define ROTATE(a, n) (((a) << (n)) | (((a)&0xffffffff) >> (32 - (n))))
-#endif
-
 #if defined(DATA_ORDER_IS_BIG_ENDIAN)
 
 #if !defined(PEDANTIC) && defined(__GNUC__) && __GNUC__ >= 2 && \

crypto/md4/md4.c

@@ -103,6 +103,8 @@ void md4_block_data_order(uint32_t *state, const uint8_t *data, size_t num);
 #define G(b, c, d) (((b) & (c)) | ((b) & (d)) | ((c) & (d)))
 #define H(b, c, d) ((b) ^ (c) ^ (d))
 
+#define ROTATE(a, n) (((a) << (n)) | ((a) >> (32 - (n))))
+
 #define R0(a, b, c, d, k, s, t)        \
   {                                    \
     a += ((k) + (t)+F((b), (c), (d))); \

crypto/md5/md5.c

@@ -127,6 +127,8 @@ void md5_block_data_order(uint32_t *state, const uint8_t *data, size_t num);
 #define	H(b,c,d)	((b) ^ (c) ^ (d))
 #define	I(b,c,d)	(((~(d)) | (b)) ^ (c))
 
+#define ROTATE(a, n) (((a) << (n)) | ((a) >> (32 - (n))))
+
 #define R0(a,b,c,d,k,s,t) { \
 	a+=((k)+(t)+F((b),(c),(d))); \
 	a=ROTATE(a,s); \

crypto/sha/sha1.c

@@ -117,6 +117,7 @@ uint8_t *SHA1(const uint8_t *data, size_t len, uint8_t *out) {
 #define HASH_TRANSFORM SHA1_Transform
 #define HASH_FINAL SHA1_Final
 #define HASH_BLOCK_DATA_ORDER sha1_block_data_order
+#define ROTATE(a, n) (((a) << (n)) | ((a) >> (32 - (n))))
 #define Xupdate(a, ix, ia, ib, ic, id) \
   ((a) = (ia ^ ib ^ ic ^ id), ix = (a) = ROTATE((a), 1))
 

crypto/sha/sha256.c

@@ -204,6 +204,8 @@ static const uint32_t K256[64] = {
     0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
     0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL};
 
+#define ROTATE(a, n) (((a) << (n)) | ((a) >> (32 - (n))))
+
 /* FIPS specification refers to right rotations, while our ROTATE macro
  * is left one. This is why you might notice that rotation coefficients
  * differ from those observed in FIPS document by 32-N... */