Minor tweaks to memxor3.

diff --git a/armv7/memxor.asm b/armv7/memxor.asm
index 80e725e7d7c3174a48e6e5343d9725949eb348f5..fe4f9e8a09a20b2a4741cbfb25be26fa282f4fd0 100644 (file)
--- a/armv7/memxor.asm
+++ b/armv7/memxor.asm
@@ -232,10 +232,9 @@ PROLOGUE(memxor3)
        mov     r4, AP
        mov     AP, BP
        mov     BP, r4
-       mov     BCNT, ACNT
 
 .Lmemxor3_au:
-       C FIXME: Switch roles of A and B
+       C NOTE: We have the relevant shift count in ACNT, not BCNT
 
        C AP is aligned, BP is not
        C           v original SRC
@@ -247,7 +246,7 @@ PROLOGUE(memxor3)
        C
        C With little-endian, we need to do
        C DST[i-i] ^= (SRC[i-i] >> CNT) ^ (SRC[i] << TNC)
-       rsb     BTNC, BCNT, #32
+       rsb     ATNC, ACNT, #32
        bic     BP, #3
 
        ldr     r4, [BP]
@@ -261,14 +260,14 @@ PROLOGUE(memxor3)
 .Lmemxor3_au_loop:
        ldr     r5, [BP, #-4]!
        ldr     r6, [AP, #-4]!
-       eor     r6, r6, r4, lsl BTNC
-       eor     r6, r6, r5, lsr BCNT
+       eor     r6, r6, r4, lsl ATNC
+       eor     r6, r6, r5, lsr ACNT
        str     r6, [DST, #-4]!
 .Lmemxor3_au_odd:
        ldr     r4, [BP, #-4]!
        ldr     r6, [AP, #-4]!
-       eor     r6, r6, r5, lsl BTNC
-       eor     r6, r6, r4, lsr BCNT
+       eor     r6, r6, r5, lsl ATNC
+       eor     r6, r6, r4, lsr ACNT
        str     r6, [DST, #-4]!
        subs    N, #8
        bcs     .Lmemxor3_au_loop
@@ -277,10 +276,7 @@ PROLOGUE(memxor3)
 
        C Leftover bytes in r4, low end
        ldr     r5, [AP, #-4]
-       C FIXME: Do this with a single shift/rotate?
-       lsr     r5, BTNC
-       eor     r4, r5
-       ror     r4, BCNT
+       eor     r4, r5, r4, lsl ATNC
 
 .Lmemxor3_au_leftover:
        C Store a byte at a time
@@ -288,14 +284,14 @@ PROLOGUE(memxor3)
        strb    r4, [DST, #-1]!
        subs    N, #1
        beq     .Lmemxor3_done
-       subs    BCNT, #8
+       subs    ACNT, #8
        sub     AP, #1
        bne     .Lmemxor3_au_leftover
        b       .Lmemxor3_bytes
 
 .Lmemxor3_a_aligned:
-       ands    BCNT, BP, #3
-       lsl     BCNT, #3
+       ands    ACNT, BP, #3
+       lsl     ACNT, #3
        bne     .Lmemxor3_au ;
 
        C a, b and dst all have the same alignment.