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|
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !math_big_pure_go,s390x
#include "textflag.h"
// This file provides fast assembly versions for the elementary
// arithmetic operations on vectors implemented in arith.go.
TEXT ·mulWW(SB), NOSPLIT, $0
MOVD x+0(FP), R3
MOVD y+8(FP), R4
MULHDU R3, R4
MOVD R10, z1+16(FP)
MOVD R11, z0+24(FP)
RET
// func divWW(x1, x0, y Word) (q, r Word)
TEXT ·divWW(SB), NOSPLIT, $0
MOVD x1+0(FP), R10
MOVD x0+8(FP), R11
MOVD y+16(FP), R5
WORD $0xb98700a5 // dlgr r10,r5
MOVD R11, q+24(FP)
MOVD R10, r+32(FP)
RET
// DI = R3, CX = R4, SI = r10, r8 = r8, r9=r9, r10 = r2 , r11 = r5, r12 = r6, r13 = r7, r14 = r1 (R0 set to 0) + use R11
// func addVV(z, x, y []Word) (c Word)
TEXT ·addVV(SB), NOSPLIT, $0
MOVD addvectorfacility+0x00(SB), R1
BR (R1)
TEXT ·addVV_check(SB), NOSPLIT, $0
MOVB ·hasVX(SB), R1
CMPBEQ R1, $1, vectorimpl // vectorfacility = 1, vector supported
MOVD $addvectorfacility+0x00(SB), R1
MOVD $·addVV_novec(SB), R2
MOVD R2, 0(R1)
// MOVD $·addVV_novec(SB), 0(R1)
BR ·addVV_novec(SB)
vectorimpl:
MOVD $addvectorfacility+0x00(SB), R1
MOVD $·addVV_vec(SB), R2
MOVD R2, 0(R1)
// MOVD $·addVV_vec(SB), 0(R1)
BR ·addVV_vec(SB)
GLOBL addvectorfacility+0x00(SB), NOPTR, $8
DATA addvectorfacility+0x00(SB)/8, $·addVV_check(SB)
TEXT ·addVV_vec(SB), NOSPLIT, $0
MOVD z_len+8(FP), R3
MOVD x+24(FP), R8
MOVD y+48(FP), R9
MOVD z+0(FP), R2
MOVD $0, R4 // c = 0
MOVD $0, R0 // make sure it's zero
MOVD $0, R10 // i = 0
// s/JL/JMP/ below to disable the unrolled loop
SUB $4, R3
BLT v1
SUB $12, R3 // n -= 16
BLT A1 // if n < 0 goto A1
MOVD R8, R5
MOVD R9, R6
MOVD R2, R7
// n >= 0
// regular loop body unrolled 16x
VZERO V0 // c = 0
UU1:
VLM 0(R5), V1, V4 // 64-bytes into V1..V8
ADD $64, R5
VPDI $0x4, V1, V1, V1 // flip the doublewords to big-endian order
VPDI $0x4, V2, V2, V2 // flip the doublewords to big-endian order
VLM 0(R6), V9, V12 // 64-bytes into V9..V16
ADD $64, R6
VPDI $0x4, V9, V9, V9 // flip the doublewords to big-endian order
VPDI $0x4, V10, V10, V10 // flip the doublewords to big-endian order
VACCCQ V1, V9, V0, V25
VACQ V1, V9, V0, V17
VACCCQ V2, V10, V25, V26
VACQ V2, V10, V25, V18
VLM 0(R5), V5, V6 // 32-bytes into V1..V8
VLM 0(R6), V13, V14 // 32-bytes into V9..V16
ADD $32, R5
ADD $32, R6
VPDI $0x4, V3, V3, V3 // flip the doublewords to big-endian order
VPDI $0x4, V4, V4, V4 // flip the doublewords to big-endian order
VPDI $0x4, V11, V11, V11 // flip the doublewords to big-endian order
VPDI $0x4, V12, V12, V12 // flip the doublewords to big-endian order
VACCCQ V3, V11, V26, V27
VACQ V3, V11, V26, V19
VACCCQ V4, V12, V27, V28
VACQ V4, V12, V27, V20
VLM 0(R5), V7, V8 // 32-bytes into V1..V8
VLM 0(R6), V15, V16 // 32-bytes into V9..V16
ADD $32, R5
ADD $32, R6
VPDI $0x4, V5, V5, V5 // flip the doublewords to big-endian order
VPDI $0x4, V6, V6, V6 // flip the doublewords to big-endian order
VPDI $0x4, V13, V13, V13 // flip the doublewords to big-endian order
VPDI $0x4, V14, V14, V14 // flip the doublewords to big-endian order
VACCCQ V5, V13, V28, V29
VACQ V5, V13, V28, V21
VACCCQ V6, V14, V29, V30
VACQ V6, V14, V29, V22
VPDI $0x4, V7, V7, V7 // flip the doublewords to big-endian order
VPDI $0x4, V8, V8, V8 // flip the doublewords to big-endian order
VPDI $0x4, V15, V15, V15 // flip the doublewords to big-endian order
VPDI $0x4, V16, V16, V16 // flip the doublewords to big-endian order
VACCCQ V7, V15, V30, V31
VACQ V7, V15, V30, V23
VACCCQ V8, V16, V31, V0 // V0 has carry-over
VACQ V8, V16, V31, V24
VPDI $0x4, V17, V17, V17 // flip the doublewords to big-endian order
VPDI $0x4, V18, V18, V18 // flip the doublewords to big-endian order
VPDI $0x4, V19, V19, V19 // flip the doublewords to big-endian order
VPDI $0x4, V20, V20, V20 // flip the doublewords to big-endian order
VPDI $0x4, V21, V21, V21 // flip the doublewords to big-endian order
VPDI $0x4, V22, V22, V22 // flip the doublewords to big-endian order
VPDI $0x4, V23, V23, V23 // flip the doublewords to big-endian order
VPDI $0x4, V24, V24, V24 // flip the doublewords to big-endian order
VSTM V17, V24, 0(R7) // 128-bytes into z
ADD $128, R7
ADD $128, R10 // i += 16
SUB $16, R3 // n -= 16
BGE UU1 // if n >= 0 goto U1
VLGVG $1, V0, R4 // put cf into R4
NEG R4, R4 // save cf
A1:
ADD $12, R3 // n += 16
// s/JL/JMP/ below to disable the unrolled loop
BLT v1 // if n < 0 goto v1
U1: // n >= 0
// regular loop body unrolled 4x
MOVD 0(R8)(R10*1), R5
MOVD 8(R8)(R10*1), R6
MOVD 16(R8)(R10*1), R7
MOVD 24(R8)(R10*1), R1
ADDC R4, R4 // restore CF
MOVD 0(R9)(R10*1), R11
ADDE R11, R5
MOVD 8(R9)(R10*1), R11
ADDE R11, R6
MOVD 16(R9)(R10*1), R11
ADDE R11, R7
MOVD 24(R9)(R10*1), R11
ADDE R11, R1
MOVD R0, R4
ADDE R4, R4 // save CF
NEG R4, R4
MOVD R5, 0(R2)(R10*1)
MOVD R6, 8(R2)(R10*1)
MOVD R7, 16(R2)(R10*1)
MOVD R1, 24(R2)(R10*1)
ADD $32, R10 // i += 4
SUB $4, R3 // n -= 4
BGE U1 // if n >= 0 goto U1
v1:
ADD $4, R3 // n += 4
BLE E1 // if n <= 0 goto E1
L1: // n > 0
ADDC R4, R4 // restore CF
MOVD 0(R8)(R10*1), R5
MOVD 0(R9)(R10*1), R11
ADDE R11, R5
MOVD R5, 0(R2)(R10*1)
MOVD R0, R4
ADDE R4, R4 // save CF
NEG R4, R4
ADD $8, R10 // i++
SUB $1, R3 // n--
BGT L1 // if n > 0 goto L1
E1:
NEG R4, R4
MOVD R4, c+72(FP) // return c
RET
TEXT ·addVV_novec(SB), NOSPLIT, $0
novec:
MOVD z_len+8(FP), R3
MOVD x+24(FP), R8
MOVD y+48(FP), R9
MOVD z+0(FP), R2
MOVD $0, R4 // c = 0
MOVD $0, R0 // make sure it's zero
MOVD $0, R10 // i = 0
// s/JL/JMP/ below to disable the unrolled loop
SUB $4, R3 // n -= 4
BLT v1n // if n < 0 goto v1n
U1n: // n >= 0
// regular loop body unrolled 4x
MOVD 0(R8)(R10*1), R5
MOVD 8(R8)(R10*1), R6
MOVD 16(R8)(R10*1), R7
MOVD 24(R8)(R10*1), R1
ADDC R4, R4 // restore CF
MOVD 0(R9)(R10*1), R11
ADDE R11, R5
MOVD 8(R9)(R10*1), R11
ADDE R11, R6
MOVD 16(R9)(R10*1), R11
ADDE R11, R7
MOVD 24(R9)(R10*1), R11
ADDE R11, R1
MOVD R0, R4
ADDE R4, R4 // save CF
NEG R4, R4
MOVD R5, 0(R2)(R10*1)
MOVD R6, 8(R2)(R10*1)
MOVD R7, 16(R2)(R10*1)
MOVD R1, 24(R2)(R10*1)
ADD $32, R10 // i += 4
SUB $4, R3 // n -= 4
BGE U1n // if n >= 0 goto U1n
v1n:
ADD $4, R3 // n += 4
BLE E1n // if n <= 0 goto E1n
L1n: // n > 0
ADDC R4, R4 // restore CF
MOVD 0(R8)(R10*1), R5
MOVD 0(R9)(R10*1), R11
ADDE R11, R5
MOVD R5, 0(R2)(R10*1)
MOVD R0, R4
ADDE R4, R4 // save CF
NEG R4, R4
ADD $8, R10 // i++
SUB $1, R3 // n--
BGT L1n // if n > 0 goto L1n
E1n:
NEG R4, R4
MOVD R4, c+72(FP) // return c
RET
TEXT ·subVV(SB), NOSPLIT, $0
MOVD subvectorfacility+0x00(SB), R1
BR (R1)
TEXT ·subVV_check(SB), NOSPLIT, $0
MOVB ·hasVX(SB), R1
CMPBEQ R1, $1, vectorimpl // vectorfacility = 1, vector supported
MOVD $subvectorfacility+0x00(SB), R1
MOVD $·subVV_novec(SB), R2
MOVD R2, 0(R1)
// MOVD $·subVV_novec(SB), 0(R1)
BR ·subVV_novec(SB)
vectorimpl:
MOVD $subvectorfacility+0x00(SB), R1
MOVD $·subVV_vec(SB), R2
MOVD R2, 0(R1)
// MOVD $·subVV_vec(SB), 0(R1)
BR ·subVV_vec(SB)
GLOBL subvectorfacility+0x00(SB), NOPTR, $8
DATA subvectorfacility+0x00(SB)/8, $·subVV_check(SB)
// DI = R3, CX = R4, SI = r10, r8 = r8, r9=r9, r10 = r2 , r11 = r5, r12 = r6, r13 = r7, r14 = r1 (R0 set to 0) + use R11
// func subVV(z, x, y []Word) (c Word)
// (same as addVV except for SUBC/SUBE instead of ADDC/ADDE and label names)
TEXT ·subVV_vec(SB), NOSPLIT, $0
MOVD z_len+8(FP), R3
MOVD x+24(FP), R8
MOVD y+48(FP), R9
MOVD z+0(FP), R2
MOVD $0, R4 // c = 0
MOVD $0, R0 // make sure it's zero
MOVD $0, R10 // i = 0
// s/JL/JMP/ below to disable the unrolled loop
SUB $4, R3 // n -= 4
BLT v1 // if n < 0 goto v1
SUB $12, R3 // n -= 16
BLT A1 // if n < 0 goto A1
MOVD R8, R5
MOVD R9, R6
MOVD R2, R7
// n >= 0
// regular loop body unrolled 16x
VZERO V0 // cf = 0
MOVD $1, R4 // for 390 subtraction cf starts as 1 (no borrow)
VLVGG $1, R4, V0 // put carry into V0
UU1:
VLM 0(R5), V1, V4 // 64-bytes into V1..V8
ADD $64, R5
VPDI $0x4, V1, V1, V1 // flip the doublewords to big-endian order
VPDI $0x4, V2, V2, V2 // flip the doublewords to big-endian order
VLM 0(R6), V9, V12 // 64-bytes into V9..V16
ADD $64, R6
VPDI $0x4, V9, V9, V9 // flip the doublewords to big-endian order
VPDI $0x4, V10, V10, V10 // flip the doublewords to big-endian order
VSBCBIQ V1, V9, V0, V25
VSBIQ V1, V9, V0, V17
VSBCBIQ V2, V10, V25, V26
VSBIQ V2, V10, V25, V18
VLM 0(R5), V5, V6 // 32-bytes into V1..V8
VLM 0(R6), V13, V14 // 32-bytes into V9..V16
ADD $32, R5
ADD $32, R6
VPDI $0x4, V3, V3, V3 // flip the doublewords to big-endian order
VPDI $0x4, V4, V4, V4 // flip the doublewords to big-endian order
VPDI $0x4, V11, V11, V11 // flip the doublewords to big-endian order
VPDI $0x4, V12, V12, V12 // flip the doublewords to big-endian order
VSBCBIQ V3, V11, V26, V27
VSBIQ V3, V11, V26, V19
VSBCBIQ V4, V12, V27, V28
VSBIQ V4, V12, V27, V20
VLM 0(R5), V7, V8 // 32-bytes into V1..V8
VLM 0(R6), V15, V16 // 32-bytes into V9..V16
ADD $32, R5
ADD $32, R6
VPDI $0x4, V5, V5, V5 // flip the doublewords to big-endian order
VPDI $0x4, V6, V6, V6 // flip the doublewords to big-endian order
VPDI $0x4, V13, V13, V13 // flip the doublewords to big-endian order
VPDI $0x4, V14, V14, V14 // flip the doublewords to big-endian order
VSBCBIQ V5, V13, V28, V29
VSBIQ V5, V13, V28, V21
VSBCBIQ V6, V14, V29, V30
VSBIQ V6, V14, V29, V22
VPDI $0x4, V7, V7, V7 // flip the doublewords to big-endian order
VPDI $0x4, V8, V8, V8 // flip the doublewords to big-endian order
VPDI $0x4, V15, V15, V15 // flip the doublewords to big-endian order
VPDI $0x4, V16, V16, V16 // flip the doublewords to big-endian order
VSBCBIQ V7, V15, V30, V31
VSBIQ V7, V15, V30, V23
VSBCBIQ V8, V16, V31, V0 // V0 has carry-over
VSBIQ V8, V16, V31, V24
VPDI $0x4, V17, V17, V17 // flip the doublewords to big-endian order
VPDI $0x4, V18, V18, V18 // flip the doublewords to big-endian order
VPDI $0x4, V19, V19, V19 // flip the doublewords to big-endian order
VPDI $0x4, V20, V20, V20 // flip the doublewords to big-endian order
VPDI $0x4, V21, V21, V21 // flip the doublewords to big-endian order
VPDI $0x4, V22, V22, V22 // flip the doublewords to big-endian order
VPDI $0x4, V23, V23, V23 // flip the doublewords to big-endian order
VPDI $0x4, V24, V24, V24 // flip the doublewords to big-endian order
VSTM V17, V24, 0(R7) // 128-bytes into z
ADD $128, R7
ADD $128, R10 // i += 16
SUB $16, R3 // n -= 16
BGE UU1 // if n >= 0 goto U1
VLGVG $1, V0, R4 // put cf into R4
SUB $1, R4 // save cf
A1:
ADD $12, R3 // n += 16
BLT v1 // if n < 0 goto v1
U1: // n >= 0
// regular loop body unrolled 4x
MOVD 0(R8)(R10*1), R5
MOVD 8(R8)(R10*1), R6
MOVD 16(R8)(R10*1), R7
MOVD 24(R8)(R10*1), R1
MOVD R0, R11
SUBC R4, R11 // restore CF
MOVD 0(R9)(R10*1), R11
SUBE R11, R5
MOVD 8(R9)(R10*1), R11
SUBE R11, R6
MOVD 16(R9)(R10*1), R11
SUBE R11, R7
MOVD 24(R9)(R10*1), R11
SUBE R11, R1
MOVD R0, R4
SUBE R4, R4 // save CF
MOVD R5, 0(R2)(R10*1)
MOVD R6, 8(R2)(R10*1)
MOVD R7, 16(R2)(R10*1)
MOVD R1, 24(R2)(R10*1)
ADD $32, R10 // i += 4
SUB $4, R3 // n -= 4
BGE U1 // if n >= 0 goto U1n
v1:
ADD $4, R3 // n += 4
BLE E1 // if n <= 0 goto E1
L1: // n > 0
MOVD R0, R11
SUBC R4, R11 // restore CF
MOVD 0(R8)(R10*1), R5
MOVD 0(R9)(R10*1), R11
SUBE R11, R5
MOVD R5, 0(R2)(R10*1)
MOVD R0, R4
SUBE R4, R4 // save CF
ADD $8, R10 // i++
SUB $1, R3 // n--
BGT L1 // if n > 0 goto L1n
E1:
NEG R4, R4
MOVD R4, c+72(FP) // return c
RET
// DI = R3, CX = R4, SI = r10, r8 = r8, r9=r9, r10 = r2 , r11 = r5, r12 = r6, r13 = r7, r14 = r1 (R0 set to 0) + use R11
// func subVV(z, x, y []Word) (c Word)
// (same as addVV except for SUBC/SUBE instead of ADDC/ADDE and label names)
TEXT ·subVV_novec(SB), NOSPLIT, $0
MOVD z_len+8(FP), R3
MOVD x+24(FP), R8
MOVD y+48(FP), R9
MOVD z+0(FP), R2
MOVD $0, R4 // c = 0
MOVD $0, R0 // make sure it's zero
MOVD $0, R10 // i = 0
// s/JL/JMP/ below to disable the unrolled loop
SUB $4, R3 // n -= 4
BLT v1 // if n < 0 goto v1
U1: // n >= 0
// regular loop body unrolled 4x
MOVD 0(R8)(R10*1), R5
MOVD 8(R8)(R10*1), R6
MOVD 16(R8)(R10*1), R7
MOVD 24(R8)(R10*1), R1
MOVD R0, R11
SUBC R4, R11 // restore CF
MOVD 0(R9)(R10*1), R11
SUBE R11, R5
MOVD 8(R9)(R10*1), R11
SUBE R11, R6
MOVD 16(R9)(R10*1), R11
SUBE R11, R7
MOVD 24(R9)(R10*1), R11
SUBE R11, R1
MOVD R0, R4
SUBE R4, R4 // save CF
MOVD R5, 0(R2)(R10*1)
MOVD R6, 8(R2)(R10*1)
MOVD R7, 16(R2)(R10*1)
MOVD R1, 24(R2)(R10*1)
ADD $32, R10 // i += 4
SUB $4, R3 // n -= 4
BGE U1 // if n >= 0 goto U1
v1:
ADD $4, R3 // n += 4
BLE E1 // if n <= 0 goto E1
L1: // n > 0
MOVD R0, R11
SUBC R4, R11 // restore CF
MOVD 0(R8)(R10*1), R5
MOVD 0(R9)(R10*1), R11
SUBE R11, R5
MOVD R5, 0(R2)(R10*1)
MOVD R0, R4
SUBE R4, R4 // save CF
ADD $8, R10 // i++
SUB $1, R3 // n--
BGT L1 // if n > 0 goto L1
E1:
NEG R4, R4
MOVD R4, c+72(FP) // return c
RET
TEXT ·addVW(SB), NOSPLIT, $0
MOVD z_len+8(FP), R5 // length of z
MOVD x+24(FP), R6
MOVD y+48(FP), R7 // c = y
MOVD z+0(FP), R8
CMPBEQ R5, $0, returnC // if len(z) == 0, we can have an early return
// Add the first two words, and determine which path (copy path or loop path) to take based on the carry flag.
ADDC 0(R6), R7
MOVD R7, 0(R8)
CMPBEQ R5, $1, returnResult // len(z) == 1
MOVD $0, R9
ADDE 8(R6), R9
MOVD R9, 8(R8)
CMPBEQ R5, $2, returnResult // len(z) == 2
// Update the counters
MOVD $16, R12 // i = 2
MOVD $-2(R5), R5 // n = n - 2
loopOverEachWord:
BRC $12, copySetup // carry = 0, copy the rest
MOVD $1, R9
// Originally we used the carry flag generated in the previous iteration
// (i.e: ADDE could be used here to do the addition). However, since we
// already know carry is 1 (otherwise we will go to copy section), we can use
// ADDC here so the current iteration does not depend on the carry flag
// generated in the previous iteration. This could be useful when branch prediction happens.
ADDC 0(R6)(R12*1), R9
MOVD R9, 0(R8)(R12*1) // z[i] = x[i] + c
MOVD $8(R12), R12 // i++
BRCTG R5, loopOverEachWord // n--
// Return the current carry value
returnResult:
MOVD $0, R0
ADDE R0, R0
MOVD R0, c+56(FP)
RET
// Update position of x(R6) and z(R8) based on the current counter value and perform copying.
// With the assumption that x and z will not overlap with each other or x and z will
// point to same memory region, we can use a faster version of copy using only MVC here.
// In the following implementation, we have three copy loops, each copying a word, 4 words, and
// 32 words at a time. Via benchmarking, this implementation is faster than calling runtime·memmove.
copySetup:
ADD R12, R6
ADD R12, R8
CMPBGE R5, $4, mediumLoop
smallLoop: // does a loop unrolling to copy word when n < 4
CMPBEQ R5, $0, returnZero
MVC $8, 0(R6), 0(R8)
CMPBEQ R5, $1, returnZero
MVC $8, 8(R6), 8(R8)
CMPBEQ R5, $2, returnZero
MVC $8, 16(R6), 16(R8)
returnZero:
MOVD $0, c+56(FP) // return 0 as carry
RET
mediumLoop:
CMPBLT R5, $4, smallLoop
CMPBLT R5, $32, mediumLoopBody
largeLoop: // Copying 256 bytes at a time.
MVC $256, 0(R6), 0(R8)
MOVD $256(R6), R6
MOVD $256(R8), R8
MOVD $-32(R5), R5
CMPBGE R5, $32, largeLoop
BR mediumLoop
mediumLoopBody: // Copying 32 bytes at a time
MVC $32, 0(R6), 0(R8)
MOVD $32(R6), R6
MOVD $32(R8), R8
MOVD $-4(R5), R5
CMPBGE R5, $4, mediumLoopBody
BR smallLoop
returnC:
MOVD R7, c+56(FP)
RET
TEXT ·subVW(SB), NOSPLIT, $0
MOVD z_len+8(FP), R5
MOVD x+24(FP), R6
MOVD y+48(FP), R7 // The borrow bit passed in
MOVD z+0(FP), R8
MOVD $0, R0 // R0 is a temporary variable used during computation. Ensure it has zero in it.
CMPBEQ R5, $0, returnC // len(z) == 0, have an early return
// Subtract the first two words, and determine which path (copy path or loop path) to take based on the borrow flag
MOVD 0(R6), R9
SUBC R7, R9
MOVD R9, 0(R8)
CMPBEQ R5, $1, returnResult
MOVD 8(R6), R9
SUBE R0, R9
MOVD R9, 8(R8)
CMPBEQ R5, $2, returnResult
// Update the counters
MOVD $16, R12 // i = 2
MOVD $-2(R5), R5 // n = n - 2
loopOverEachWord:
BRC $3, copySetup // no borrow, copy the rest
MOVD 0(R6)(R12*1), R9
// Originally we used the borrow flag generated in the previous iteration
// (i.e: SUBE could be used here to do the subtraction). However, since we
// already know borrow is 1 (otherwise we will go to copy section), we can
// use SUBC here so the current iteration does not depend on the borrow flag
// generated in the previous iteration. This could be useful when branch prediction happens.
SUBC $1, R9
MOVD R9, 0(R8)(R12*1) // z[i] = x[i] - 1
MOVD $8(R12), R12 // i++
BRCTG R5, loopOverEachWord // n--
// return the current borrow value
returnResult:
SUBE R0, R0
NEG R0, R0
MOVD R0, c+56(FP)
RET
// Update position of x(R6) and z(R8) based on the current counter value and perform copying.
// With the assumption that x and z will not overlap with each other or x and z will
// point to same memory region, we can use a faster version of copy using only MVC here.
// In the following implementation, we have three copy loops, each copying a word, 4 words, and
// 32 words at a time. Via benchmarking, this implementation is faster than calling runtime·memmove.
copySetup:
ADD R12, R6
ADD R12, R8
CMPBGE R5, $4, mediumLoop
smallLoop: // does a loop unrolling to copy word when n < 4
CMPBEQ R5, $0, returnZero
MVC $8, 0(R6), 0(R8)
CMPBEQ R5, $1, returnZero
MVC $8, 8(R6), 8(R8)
CMPBEQ R5, $2, returnZero
MVC $8, 16(R6), 16(R8)
returnZero:
MOVD $0, c+56(FP) // return 0 as borrow
RET
mediumLoop:
CMPBLT R5, $4, smallLoop
CMPBLT R5, $32, mediumLoopBody
largeLoop: // Copying 256 bytes at a time
MVC $256, 0(R6), 0(R8)
MOVD $256(R6), R6
MOVD $256(R8), R8
MOVD $-32(R5), R5
CMPBGE R5, $32, largeLoop
BR mediumLoop
mediumLoopBody: // Copying 32 bytes at a time
MVC $32, 0(R6), 0(R8)
MOVD $32(R6), R6
MOVD $32(R8), R8
MOVD $-4(R5), R5
CMPBGE R5, $4, mediumLoopBody
BR smallLoop
returnC:
MOVD R7, c+56(FP)
RET
// func shlVU(z, x []Word, s uint) (c Word)
TEXT ·shlVU(SB), NOSPLIT, $0
BR ·shlVU_g(SB)
// func shrVU(z, x []Word, s uint) (c Word)
TEXT ·shrVU(SB), NOSPLIT, $0
BR ·shrVU_g(SB)
// CX = R4, r8 = r8, r9=r9, r10 = r2 , r11 = r5, DX = r3, AX = r6 , BX = R1 , (R0 set to 0) + use R11 + use R7 for i
// func mulAddVWW(z, x []Word, y, r Word) (c Word)
TEXT ·mulAddVWW(SB), NOSPLIT, $0
MOVD z+0(FP), R2
MOVD x+24(FP), R8
MOVD y+48(FP), R9
MOVD r+56(FP), R4 // c = r
MOVD z_len+8(FP), R5
MOVD $0, R1 // i = 0
MOVD $0, R7 // i*8 = 0
MOVD $0, R0 // make sure it's zero
BR E5
L5:
MOVD (R8)(R1*1), R6
MULHDU R9, R6
ADDC R4, R11 // add to low order bits
ADDE R0, R6
MOVD R11, (R2)(R1*1)
MOVD R6, R4
ADD $8, R1 // i*8 + 8
ADD $1, R7 // i++
E5:
CMPBLT R7, R5, L5 // i < n
MOVD R4, c+64(FP)
RET
// func addMulVVW(z, x []Word, y Word) (c Word)
// CX = R4, r8 = r8, r9=r9, r10 = r2 , r11 = r5, AX = r11, DX = R6, r12=r12, BX = R1 , (R0 set to 0) + use R11 + use R7 for i
TEXT ·addMulVVW(SB), NOSPLIT, $0
MOVD z+0(FP), R2
MOVD x+24(FP), R8
MOVD y+48(FP), R9
MOVD z_len+8(FP), R5
MOVD $0, R1 // i*8 = 0
MOVD $0, R7 // i = 0
MOVD $0, R0 // make sure it's zero
MOVD $0, R4 // c = 0
MOVD R5, R12
AND $-2, R12
CMPBGE R5, $2, A6
BR E6
A6:
MOVD (R8)(R1*1), R6
MULHDU R9, R6
MOVD (R2)(R1*1), R10
ADDC R10, R11 // add to low order bits
ADDE R0, R6
ADDC R4, R11
ADDE R0, R6
MOVD R6, R4
MOVD R11, (R2)(R1*1)
MOVD (8)(R8)(R1*1), R6
MULHDU R9, R6
MOVD (8)(R2)(R1*1), R10
ADDC R10, R11 // add to low order bits
ADDE R0, R6
ADDC R4, R11
ADDE R0, R6
MOVD R6, R4
MOVD R11, (8)(R2)(R1*1)
ADD $16, R1 // i*8 + 8
ADD $2, R7 // i++
CMPBLT R7, R12, A6
BR E6
L6:
MOVD (R8)(R1*1), R6
MULHDU R9, R6
MOVD (R2)(R1*1), R10
ADDC R10, R11 // add to low order bits
ADDE R0, R6
ADDC R4, R11
ADDE R0, R6
MOVD R6, R4
MOVD R11, (R2)(R1*1)
ADD $8, R1 // i*8 + 8
ADD $1, R7 // i++
E6:
CMPBLT R7, R5, L6 // i < n
MOVD R4, c+56(FP)
RET
// func divWVW(z []Word, xn Word, x []Word, y Word) (r Word)
// CX = R4, r8 = r8, r9=r9, r10 = r2 , r11 = r5, AX = r11, DX = R6, r12=r12, BX = R1(*8) , (R0 set to 0) + use R11 + use R7 for i
TEXT ·divWVW(SB), NOSPLIT, $0
MOVD z+0(FP), R2
MOVD xn+24(FP), R10 // r = xn
MOVD x+32(FP), R8
MOVD y+56(FP), R9
MOVD z_len+8(FP), R7 // i = z
SLD $3, R7, R1 // i*8
MOVD $0, R0 // make sure it's zero
BR E7
L7:
MOVD (R8)(R1*1), R11
WORD $0xB98700A9 // DLGR R10,R9
MOVD R11, (R2)(R1*1)
E7:
SUB $1, R7 // i--
SUB $8, R1
BGE L7 // i >= 0
MOVD R10, r+64(FP)
RET
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