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authorParménides GV <parmegv@sdf.org>2014-04-08 11:38:09 +0200
committerParménides GV <parmegv@sdf.org>2014-04-08 11:43:27 +0200
commit5fc5d37330d3535a0f421632694d1e7918fc22d7 (patch)
tree1aad0c286e58962c8895854907e530b9bc9bce5a /app/openssl/crypto/bn/asm/armv4-mont.s
parentc206a91d320995f37f8abb33188bfd384249da3d (diff)
Compiles correctly: app/build-native + gradle.
Diffstat (limited to 'app/openssl/crypto/bn/asm/armv4-mont.s')
-rw-r--r--app/openssl/crypto/bn/asm/armv4-mont.s145
1 files changed, 145 insertions, 0 deletions
diff --git a/app/openssl/crypto/bn/asm/armv4-mont.s b/app/openssl/crypto/bn/asm/armv4-mont.s
new file mode 100644
index 00000000..0488455f
--- /dev/null
+++ b/app/openssl/crypto/bn/asm/armv4-mont.s
@@ -0,0 +1,145 @@
+.text
+
+.global bn_mul_mont
+.type bn_mul_mont,%function
+
+.align 2
+bn_mul_mont:
+ stmdb sp!,{r0,r2} @ sp points at argument block
+ ldr r0,[sp,#3*4] @ load num
+ cmp r0,#2
+ movlt r0,#0
+ addlt sp,sp,#2*4
+ blt .Labrt
+
+ stmdb sp!,{r4-r12,lr} @ save 10 registers
+
+ mov r0,r0,lsl#2 @ rescale r0 for byte count
+ sub sp,sp,r0 @ alloca(4*num)
+ sub sp,sp,#4 @ +extra dword
+ sub r0,r0,#4 @ "num=num-1"
+ add r4,r2,r0 @ &bp[num-1]
+
+ add r0,sp,r0 @ r0 to point at &tp[num-1]
+ ldr r8,[r0,#14*4] @ &n0
+ ldr r2,[r2] @ bp[0]
+ ldr r5,[r1],#4 @ ap[0],ap++
+ ldr r6,[r3],#4 @ np[0],np++
+ ldr r8,[r8] @ *n0
+ str r4,[r0,#15*4] @ save &bp[num]
+
+ umull r10,r11,r5,r2 @ ap[0]*bp[0]
+ str r8,[r0,#14*4] @ save n0 value
+ mul r8,r10,r8 @ "tp[0]"*n0
+ mov r12,#0
+ umlal r10,r12,r6,r8 @ np[0]*n0+"t[0]"
+ mov r4,sp
+
+.L1st:
+ ldr r5,[r1],#4 @ ap[j],ap++
+ mov r10,r11
+ mov r11,#0
+ umlal r10,r11,r5,r2 @ ap[j]*bp[0]
+ ldr r6,[r3],#4 @ np[j],np++
+ mov r14,#0
+ umlal r12,r14,r6,r8 @ np[j]*n0
+ adds r12,r12,r10
+ str r12,[r4],#4 @ tp[j-1]=,tp++
+ adc r12,r14,#0
+ cmp r4,r0
+ bne .L1st
+
+ adds r12,r12,r11
+ mov r14,#0
+ adc r14,r14,#0
+ ldr r4,[r0,#13*4] @ restore bp
+ str r12,[r0] @ tp[num-1]=
+ ldr r8,[r0,#14*4] @ restore n0
+ str r14,[r0,#4] @ tp[num]=
+
+.Louter:
+ sub r7,r0,sp @ "original" r0-1 value
+ sub r1,r1,r7 @ "rewind" ap to &ap[1]
+ sub r3,r3,r7 @ "rewind" np to &np[1]
+ ldr r2,[r4,#4]! @ *(++bp)
+ ldr r5,[r1,#-4] @ ap[0]
+ ldr r6,[r3,#-4] @ np[0]
+ ldr r10,[sp] @ tp[0]
+ ldr r7,[sp,#4] @ tp[1]
+
+ mov r11,#0
+ umlal r10,r11,r5,r2 @ ap[0]*bp[i]+tp[0]
+ str r4,[r0,#13*4] @ save bp
+ mul r8,r10,r8
+ mov r12,#0
+ umlal r10,r12,r6,r8 @ np[0]*n0+"tp[0]"
+ mov r4,sp
+
+.Linner:
+ ldr r5,[r1],#4 @ ap[j],ap++
+ adds r10,r11,r7 @ +=tp[j]
+ mov r11,#0
+ umlal r10,r11,r5,r2 @ ap[j]*bp[i]
+ ldr r6,[r3],#4 @ np[j],np++
+ mov r14,#0
+ umlal r12,r14,r6,r8 @ np[j]*n0
+ ldr r7,[r4,#8] @ tp[j+1]
+ adc r11,r11,#0
+ adds r12,r12,r10
+ str r12,[r4],#4 @ tp[j-1]=,tp++
+ adc r12,r14,#0
+ cmp r4,r0
+ bne .Linner
+
+ adds r12,r12,r11
+ mov r14,#0
+ adc r14,r14,#0
+ adds r12,r12,r7
+ adc r14,r14,#0
+ ldr r4,[r0,#13*4] @ restore bp
+ ldr r7,[r0,#15*4] @ restore &bp[num]
+ str r12,[r0] @ tp[num-1]=
+ ldr r8,[r0,#14*4] @ restore n0
+ str r14,[r0,#4] @ tp[num]=
+
+ cmp r4,r7
+ bne .Louter
+
+ ldr r2,[r0,#12*4] @ pull rp
+ add r0,r0,#4 @ r0 to point at &tp[num]
+ sub r5,r0,sp @ "original" num value
+ mov r4,sp @ "rewind" r4
+ mov r1,r4 @ "borrow" r1
+ sub r3,r3,r5 @ "rewind" r3 to &np[0]
+
+ subs r7,r7,r7 @ "clear" carry flag
+.Lsub: ldr r7,[r4],#4
+ ldr r6,[r3],#4
+ sbcs r7,r7,r6 @ tp[j]-np[j]
+ str r7,[r2],#4 @ rp[j]=
+ teq r4,r0 @ preserve carry
+ bne .Lsub
+ sbcs r14,r14,#0 @ upmost carry
+ mov r4,sp @ "rewind" r4
+ sub r2,r2,r5 @ "rewind" r2
+
+ and r1,r4,r14
+ bic r3,r2,r14
+ orr r1,r1,r3 @ ap=borrow?tp:rp
+
+.Lcopy: ldr r7,[r1],#4 @ copy or in-place refresh
+ str sp,[r4],#4 @ zap tp
+ str r7,[r2],#4
+ cmp r4,r0
+ bne .Lcopy
+
+ add sp,r0,#4 @ skip over tp[num+1]
+ ldmia sp!,{r4-r12,lr} @ restore registers
+ add sp,sp,#2*4 @ skip over {r0,r2}
+ mov r0,#1
+.Labrt: tst lr,#1
+ moveq pc,lr @ be binary compatible with V4, yet
+ .word 0xe12fff1e @ interoperable with Thumb ISA:-)
+.size bn_mul_mont,.-bn_mul_mont
+.asciz "Montgomery multiplication for ARMv4, CRYPTOGAMS by <appro@openssl.org>"
+.align 2