* sparc/machine.m4 (AES_ROUND): New loop invariants T0-T3, to

avoid the additions of the AES_TABLEx constants in the inner loop.

Rev: src/nettle/sparc/aes-encrypt-internal.asm:1.8
Rev: src/nettle/sparc/machine.m4:1.8

sparc/aes-encrypt-internal.asm

@@ -19,14 +19,14 @@ C the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 C MA 02111-1307, USA.
 
 
-C Arguments
+C	Arguments
 define(<CTX>,	<%i0>)
 define(<T>,	<%i1>)
 define(<LENGTH>,<%i2>)
 define(<DST>,	<%i3>)
 define(<SRC>,	<%i4>)
 
-C AES state, two copies for unrolling
+C	AES state, two copies for unrolling
 
 define(<W0>,	<%l0>)
 define(<W1>,	<%l1>)
@@ -38,10 +38,13 @@ define(<X1>,	<%l5>)
 define(<X2>,	<%l6>)
 define(<X3>,	<%l7>)
 
-C %o0 and %01 are TMP1 and TMP2
+C	%o0-%03 are used for loop invariants T0-T3
 define(<KEY>,	<%o4>)
 define(<ROUND>, <%o5>)
 
+C %g1 and %g2 are TMP1 and TMP2
+		
+
 C Registers %g1-%g3 and %o0 - %o5 are free to use.
 
 C The sparc32 stack frame looks like
@@ -69,7 +72,12 @@ PROLOGUE(_nettle_aes_encrypt)
 	save	%sp, -FRAME_SIZE, %sp
 	cmp	LENGTH, 0
 	be	.Lend
-	nop
+
+	C	Loop invariants
+	add	T, AES_TABLE0, T0
+	add	T, AES_TABLE1, T1
+	add	T, AES_TABLE2, T2
+	add	T, AES_TABLE3, T3
 
 .Lblock_loop:
 	C  Read src, and add initial subkey
@@ -79,16 +87,16 @@ PROLOGUE(_nettle_aes_encrypt)
 	AES_LOAD(2, SRC, KEY, W2)
 	AES_LOAD(3, SRC, KEY, W3)
 
+	C	Must be even, and includes the final round
+	ld	[AES_NROUNDS + CTX], ROUND
 	add	SRC, 16, SRC
 	add	KEY, 16, KEY
 
-	C	Must be even, and includes the final round
-	ld	[AES_NROUNDS + CTX], ROUND
-	nop
 	srl	ROUND, 1, ROUND
 	C	Last two rounds handled specially
 	sub	ROUND, 1, ROUND
 .Lround_loop:
+	C The AES_ROUND macro uses T0,... T3
 	C	Transform W -> X
 	AES_ROUND(0, T, W0, W1, W2, W3, KEY, X0)
 	AES_ROUND(1, T, W1, W2, W3, W0, KEY, X1)

sparc/machine.m4

@@ -5,8 +5,14 @@ C understand arithmetic expressions? Mayby we don't need to use m4
 C eval.
 
 C Used as temporaries by the AES macros
-define(<TMP1>, <%o0>)
-define(<TMP2>, <%o1>)
+define(<TMP1>, <%g1>)
+define(<TMP2>, <%g2>)
+
+C Loop invariants used by AES_ROUND
+define(<T0>,	<%o0>)
+define(<T1>,	<%o1>)
+define(<T2>,	<%o2>)
+define(<T3>,	<%o3>)
 
 C AES_LOAD(i, src, key, res)
 define(<AES_LOAD>, <
@@ -36,23 +42,19 @@ define(<AES_ROUND>, <
 	srl	$4, 6, TMP2		C  1
 	sll	TMP1, 2, TMP1		C  0
 	and	TMP2, 0x3fc, TMP2	C  1
-	add	TMP1, AES_TABLE0, TMP1	C  0
-	add	TMP2, AES_TABLE1, TMP2	C  1
-	ld	[$2 + TMP1], $8		C  0	E0
+	ld	[T0 + TMP1], $8		C  0	E0
 	srl	$5, 14, TMP1		C  2
-	ld	[$2 + TMP2], TMP2	C  1
+	ld	[T1 + TMP2], TMP2	C  1
 	and	TMP1, 0x3fc, TMP1	C  2
 	xor	$8, TMP2, $8		C  1	E1
 	srl	$6, 22, TMP2		C  3
-	add	TMP1, AES_TABLE2, TMP1	C  2
+	ld	[T2 + TMP1], TMP1	C  2
 	and	TMP2, 0x3fc, TMP2	C  3
-	ld	[$2 + TMP1], TMP1	C  2
-	add	TMP2, AES_TABLE3, TMP2	C  3
 	xor	$8, TMP1, $8		C  2	E2
 	ld	[$7 + eval(4*$1)], TMP1	C  4
-	ld	[$2 + TMP2], TMP2	C  3
-	xor	$8, TMP1, $8		C  4
-	xor	$8, TMP2, $8		C  3
+	ld	[T3 + TMP2], TMP2	C  3
+	xor	$8, TMP1, $8		C  4	E4
+	xor	$8, TMP2, $8		C  3	E3
 >)dnl
 
 C AES_FINAL_ROUND(i, T, a, b, c, d, key, dst)