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// Copyright 2013 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.
//go:build !math_big_pure_go && (ppc64 || ppc64le)
// +build !math_big_pure_go
// +build ppc64 ppc64le
#include "textflag.h"
// This file provides fast assembly versions for the elementary
// arithmetic operations on vectors implemented in arith.go.
// func addVV(z, y, y []Word) (c Word)
// z[i] = x[i] + y[i] for all i, carrying
TEXT ·addVV(SB), NOSPLIT, $0
MOVD z_len+8(FP), R7 // R7 = z_len
MOVD x+24(FP), R8 // R8 = x[]
MOVD y+48(FP), R9 // R9 = y[]
MOVD z+0(FP), R10 // R10 = z[]
// If z_len = 0, we are done
CMP R0, R7
MOVD R0, R4
BEQ done
// Process the first iteration out of the loop so we can
// use MOVDU and avoid 3 index registers updates.
MOVD 0(R8), R11 // R11 = x[i]
MOVD 0(R9), R12 // R12 = y[i]
ADD $-1, R7 // R7 = z_len - 1
ADDC R12, R11, R15 // R15 = x[i] + y[i], set CA
CMP R0, R7
MOVD R15, 0(R10) // z[i]
BEQ final // If z_len was 1, we are done
SRD $2, R7, R5 // R5 = z_len/4
CMP R0, R5
MOVD R5, CTR // Set up loop counter
BEQ tail // If R5 = 0, we can't use the loop
// Process 4 elements per iteration. Unrolling this loop
// means a performance trade-off: we will lose performance
// for small values of z_len (0.90x in the worst case), but
// gain significant performance as z_len increases (up to
// 1.45x).
loop:
MOVD 8(R8), R11 // R11 = x[i]
MOVD 16(R8), R12 // R12 = x[i+1]
MOVD 24(R8), R14 // R14 = x[i+2]
MOVDU 32(R8), R15 // R15 = x[i+3]
MOVD 8(R9), R16 // R16 = y[i]
MOVD 16(R9), R17 // R17 = y[i+1]
MOVD 24(R9), R18 // R18 = y[i+2]
MOVDU 32(R9), R19 // R19 = y[i+3]
ADDE R11, R16, R20 // R20 = x[i] + y[i] + CA
ADDE R12, R17, R21 // R21 = x[i+1] + y[i+1] + CA
ADDE R14, R18, R22 // R22 = x[i+2] + y[i+2] + CA
ADDE R15, R19, R23 // R23 = x[i+3] + y[i+3] + CA
MOVD R20, 8(R10) // z[i]
MOVD R21, 16(R10) // z[i+1]
MOVD R22, 24(R10) // z[i+2]
MOVDU R23, 32(R10) // z[i+3]
ADD $-4, R7 // R7 = z_len - 4
BC 16, 0, loop // bdnz
// We may have more elements to read
CMP R0, R7
BEQ final
// Process the remaining elements, one at a time
tail:
MOVDU 8(R8), R11 // R11 = x[i]
MOVDU 8(R9), R16 // R16 = y[i]
ADD $-1, R7 // R7 = z_len - 1
ADDE R11, R16, R20 // R20 = x[i] + y[i] + CA
CMP R0, R7
MOVDU R20, 8(R10) // z[i]
BEQ final // If R7 = 0, we are done
MOVDU 8(R8), R11
MOVDU 8(R9), R16
ADD $-1, R7
ADDE R11, R16, R20
CMP R0, R7
MOVDU R20, 8(R10)
BEQ final
MOVD 8(R8), R11
MOVD 8(R9), R16
ADDE R11, R16, R20
MOVD R20, 8(R10)
final:
ADDZE R4 // Capture CA
done:
MOVD R4, c+72(FP)
RET
// func subVV(z, x, y []Word) (c Word)
// z[i] = x[i] - y[i] for all i, carrying
TEXT ·subVV(SB), NOSPLIT, $0
MOVD z_len+8(FP), R7 // R7 = z_len
MOVD x+24(FP), R8 // R8 = x[]
MOVD y+48(FP), R9 // R9 = y[]
MOVD z+0(FP), R10 // R10 = z[]
// If z_len = 0, we are done
CMP R0, R7
MOVD R0, R4
BEQ done
// Process the first iteration out of the loop so we can
// use MOVDU and avoid 3 index registers updates.
MOVD 0(R8), R11 // R11 = x[i]
MOVD 0(R9), R12 // R12 = y[i]
ADD $-1, R7 // R7 = z_len - 1
SUBC R12, R11, R15 // R15 = x[i] - y[i], set CA
CMP R0, R7
MOVD R15, 0(R10) // z[i]
BEQ final // If z_len was 1, we are done
SRD $2, R7, R5 // R5 = z_len/4
CMP R0, R5
MOVD R5, CTR // Set up loop counter
BEQ tail // If R5 = 0, we can't use the loop
// Process 4 elements per iteration. Unrolling this loop
// means a performance trade-off: we will lose performance
// for small values of z_len (0.92x in the worst case), but
// gain significant performance as z_len increases (up to
// 1.45x).
loop:
MOVD 8(R8), R11 // R11 = x[i]
MOVD 16(R8), R12 // R12 = x[i+1]
MOVD 24(R8), R14 // R14 = x[i+2]
MOVDU 32(R8), R15 // R15 = x[i+3]
MOVD 8(R9), R16 // R16 = y[i]
MOVD 16(R9), R17 // R17 = y[i+1]
MOVD 24(R9), R18 // R18 = y[i+2]
MOVDU 32(R9), R19 // R19 = y[i+3]
SUBE R16, R11, R20 // R20 = x[i] - y[i] + CA
SUBE R17, R12, R21 // R21 = x[i+1] - y[i+1] + CA
SUBE R18, R14, R22 // R22 = x[i+2] - y[i+2] + CA
SUBE R19, R15, R23 // R23 = x[i+3] - y[i+3] + CA
MOVD R20, 8(R10) // z[i]
MOVD R21, 16(R10) // z[i+1]
MOVD R22, 24(R10) // z[i+2]
MOVDU R23, 32(R10) // z[i+3]
ADD $-4, R7 // R7 = z_len - 4
BC 16, 0, loop // bdnz
// We may have more elements to read
CMP R0, R7
BEQ final
// Process the remaining elements, one at a time
tail:
MOVDU 8(R8), R11 // R11 = x[i]
MOVDU 8(R9), R16 // R16 = y[i]
ADD $-1, R7 // R7 = z_len - 1
SUBE R16, R11, R20 // R20 = x[i] - y[i] + CA
CMP R0, R7
MOVDU R20, 8(R10) // z[i]
BEQ final // If R7 = 0, we are done
MOVDU 8(R8), R11
MOVDU 8(R9), R16
ADD $-1, R7
SUBE R16, R11, R20
CMP R0, R7
MOVDU R20, 8(R10)
BEQ final
MOVD 8(R8), R11
MOVD 8(R9), R16
SUBE R16, R11, R20
MOVD R20, 8(R10)
final:
ADDZE R4
XOR $1, R4
done:
MOVD R4, c+72(FP)
RET
// func addVW(z, x []Word, y Word) (c Word)
TEXT ·addVW(SB), NOSPLIT, $0
MOVD z+0(FP), R10 // R10 = z[]
MOVD x+24(FP), R8 // R8 = x[]
MOVD y+48(FP), R4 // R4 = y = c
MOVD z_len+8(FP), R11 // R11 = z_len
CMP R0, R11 // If z_len is zero, return
BEQ done
// We will process the first iteration out of the loop so we capture
// the value of c. In the subsequent iterations, we will rely on the
// value of CA set here.
MOVD 0(R8), R20 // R20 = x[i]
ADD $-1, R11 // R11 = z_len - 1
ADDC R20, R4, R6 // R6 = x[i] + c
CMP R0, R11 // If z_len was 1, we are done
MOVD R6, 0(R10) // z[i]
BEQ final
// We will read 4 elements per iteration
SRD $2, R11, R9 // R9 = z_len/4
DCBT (R8)
CMP R0, R9
MOVD R9, CTR // Set up the loop counter
BEQ tail // If R9 = 0, we can't use the loop
loop:
MOVD 8(R8), R20 // R20 = x[i]
MOVD 16(R8), R21 // R21 = x[i+1]
MOVD 24(R8), R22 // R22 = x[i+2]
MOVDU 32(R8), R23 // R23 = x[i+3]
ADDZE R20, R24 // R24 = x[i] + CA
ADDZE R21, R25 // R25 = x[i+1] + CA
ADDZE R22, R26 // R26 = x[i+2] + CA
ADDZE R23, R27 // R27 = x[i+3] + CA
MOVD R24, 8(R10) // z[i]
MOVD R25, 16(R10) // z[i+1]
MOVD R26, 24(R10) // z[i+2]
MOVDU R27, 32(R10) // z[i+3]
ADD $-4, R11 // R11 = z_len - 4
BC 16, 0, loop // bdnz
// We may have some elements to read
CMP R0, R11
BEQ final
tail:
MOVDU 8(R8), R20
ADDZE R20, R24
ADD $-1, R11
MOVDU R24, 8(R10)
CMP R0, R11
BEQ final
MOVDU 8(R8), R20
ADDZE R20, R24
ADD $-1, R11
MOVDU R24, 8(R10)
CMP R0, R11
BEQ final
MOVD 8(R8), R20
ADDZE R20, R24
MOVD R24, 8(R10)
final:
ADDZE R0, R4 // c = CA
done:
MOVD R4, c+56(FP)
RET
// func subVW(z, x []Word, y Word) (c Word)
TEXT ·subVW(SB), NOSPLIT, $0
MOVD z+0(FP), R10 // R10 = z[]
MOVD x+24(FP), R8 // R8 = x[]
MOVD y+48(FP), R4 // R4 = y = c
MOVD z_len+8(FP), R11 // R11 = z_len
CMP R0, R11 // If z_len is zero, return
BEQ done
// We will process the first iteration out of the loop so we capture
// the value of c. In the subsequent iterations, we will rely on the
// value of CA set here.
MOVD 0(R8), R20 // R20 = x[i]
ADD $-1, R11 // R11 = z_len - 1
SUBC R4, R20, R6 // R6 = x[i] - c
CMP R0, R11 // If z_len was 1, we are done
MOVD R6, 0(R10) // z[i]
BEQ final
// We will read 4 elements per iteration
SRD $2, R11, R9 // R9 = z_len/4
DCBT (R8)
CMP R0, R9
MOVD R9, CTR // Set up the loop counter
BEQ tail // If R9 = 0, we can't use the loop
// The loop here is almost the same as the one used in s390x, but
// we don't need to capture CA every iteration because we've already
// done that above.
loop:
MOVD 8(R8), R20
MOVD 16(R8), R21
MOVD 24(R8), R22
MOVDU 32(R8), R23
SUBE R0, R20
SUBE R0, R21
SUBE R0, R22
SUBE R0, R23
MOVD R20, 8(R10)
MOVD R21, 16(R10)
MOVD R22, 24(R10)
MOVDU R23, 32(R10)
ADD $-4, R11
BC 16, 0, loop // bdnz
// We may have some elements to read
CMP R0, R11
BEQ final
tail:
MOVDU 8(R8), R20
SUBE R0, R20
ADD $-1, R11
MOVDU R20, 8(R10)
CMP R0, R11
BEQ final
MOVDU 8(R8), R20
SUBE R0, R20
ADD $-1, R11
MOVDU R20, 8(R10)
CMP R0, R11
BEQ final
MOVD 8(R8), R20
SUBE R0, R20
MOVD R20, 8(R10)
final:
// Capture CA
SUBE R4, R4
NEG R4, R4
done:
MOVD R4, c+56(FP)
RET
//func shlVU(z, x []Word, s uint) (c Word)
TEXT ·shlVU(SB), NOSPLIT, $0
MOVD z+0(FP), R3
MOVD x+24(FP), R6
MOVD s+48(FP), R9
MOVD z_len+8(FP), R4
MOVD x_len+32(FP), R7
CMP R9, R0 // s==0 copy(z,x)
BEQ zeroshift
CMP R4, R0 // len(z)==0 return
BEQ done
ADD $-1, R4, R5 // len(z)-1
SUBC R9, $64, R4 // ŝ=_W-s, we skip & by _W-1 as the caller ensures s < _W(64)
SLD $3, R5, R7
ADD R6, R7, R15 // save starting address &x[len(z)-1]
ADD R3, R7, R16 // save starting address &z[len(z)-1]
MOVD (R6)(R7), R14
SRD R4, R14, R7 // compute x[len(z)-1]>>ŝ into R7
CMP R5, R0 // iterate from i=len(z)-1 to 0
BEQ loopexit // Already at end?
MOVD 0(R15),R10 // x[i]
shloop:
SLD R9, R10, R10 // x[i]<<s
MOVDU -8(R15), R14
SRD R4, R14, R11 // x[i-1]>>ŝ
OR R11, R10, R10
MOVD R10, 0(R16) // z[i-1]=x[i]<<s | x[i-1]>>ŝ
MOVD R14, R10 // reuse x[i-1] for next iteration
ADD $-8, R16 // i--
CMP R15, R6 // &x[i-1]>&x[0]?
BGT shloop
loopexit:
MOVD 0(R6), R4
SLD R9, R4, R4
MOVD R4, 0(R3) // z[0]=x[0]<<s
MOVD R7, c+56(FP) // store pre-computed x[len(z)-1]>>ŝ into c
RET
zeroshift:
CMP R6, R0 // x is null, nothing to copy
BEQ done
CMP R6, R3 // if x is same as z, nothing to copy
BEQ done
CMP R7, R4
ISEL $0, R7, R4, R7 // Take the lower bound of lengths of x,z
SLD $3, R7, R7
SUB R6, R3, R11 // dest - src
CMPU R11, R7, CR2 // < len?
BLT CR2, backward // there is overlap, copy backwards
MOVD $0, R14
// shlVU processes backwards, but added a forward copy option
// since its faster on POWER
repeat:
MOVD (R6)(R14), R15 // Copy 8 bytes at a time
MOVD R15, (R3)(R14)
ADD $8, R14
CMP R14, R7 // More 8 bytes left?
BLT repeat
BR done
backward:
ADD $-8,R7, R14
repeatback:
MOVD (R6)(R14), R15 // copy x into z backwards
MOVD R15, (R3)(R14) // copy 8 bytes at a time
SUB $8, R14
CMP R14, $-8 // More 8 bytes left?
BGT repeatback
done:
MOVD R0, c+56(FP) // c=0
RET
//func shrVU(z, x []Word, s uint) (c Word)
TEXT ·shrVU(SB), NOSPLIT, $0
MOVD z+0(FP), R3
MOVD x+24(FP), R6
MOVD s+48(FP), R9
MOVD z_len+8(FP), R4
MOVD x_len+32(FP), R7
CMP R9, R0 // s==0, copy(z,x)
BEQ zeroshift
CMP R4, R0 // len(z)==0 return
BEQ done
SUBC R9, $64, R5 // ŝ=_W-s, we skip & by _W-1 as the caller ensures s < _W(64)
MOVD 0(R6), R7
SLD R5, R7, R7 // compute x[0]<<ŝ
MOVD $1, R8 // iterate from i=1 to i<len(z)
CMP R8, R4
BGE loopexit // Already at end?
// vectorize if len(z) is >=3, else jump to scalar loop
CMP R4, $3
BLT scalar
MTVSRD R9, VS38 // s
VSPLTB $7, V6, V4
MTVSRD R5, VS39 // ŝ
VSPLTB $7, V7, V2
ADD $-2, R4, R16
PCALIGN $16
loopback:
ADD $-1, R8, R10
SLD $3, R10
LXVD2X (R6)(R10), VS32 // load x[i-1], x[i]
SLD $3, R8, R12
LXVD2X (R6)(R12), VS33 // load x[i], x[i+1]
VSRD V0, V4, V3 // x[i-1]>>s, x[i]>>s
VSLD V1, V2, V5 // x[i]<<ŝ, x[i+1]<<ŝ
VOR V3, V5, V5 // Or(|) the two registers together
STXVD2X VS37, (R3)(R10) // store into z[i-1] and z[i]
ADD $2, R8 // Done processing 2 entries, i and i+1
CMP R8, R16 // Are there at least a couple of more entries left?
BLE loopback
CMP R8, R4 // Are we at the last element?
BEQ loopexit
scalar:
ADD $-1, R8, R10
SLD $3, R10
MOVD (R6)(R10),R11
SRD R9, R11, R11 // x[len(z)-2] >> s
SLD $3, R8, R12
MOVD (R6)(R12), R12
SLD R5, R12, R12 // x[len(z)-1]<<ŝ
OR R12, R11, R11 // x[len(z)-2]>>s | x[len(z)-1]<<ŝ
MOVD R11, (R3)(R10) // z[len(z)-2]=x[len(z)-2]>>s | x[len(z)-1]<<ŝ
loopexit:
ADD $-1, R4
SLD $3, R4
MOVD (R6)(R4), R5
SRD R9, R5, R5 // x[len(z)-1]>>s
MOVD R5, (R3)(R4) // z[len(z)-1]=x[len(z)-1]>>s
MOVD R7, c+56(FP) // store pre-computed x[0]<<ŝ into c
RET
zeroshift:
CMP R6, R0 // x is null, nothing to copy
BEQ done
CMP R6, R3 // if x is same as z, nothing to copy
BEQ done
CMP R7, R4
ISEL $0, R7, R4, R7 // Take the lower bounds of lengths of x, z
SLD $3, R7, R7
MOVD $0, R14
repeat:
MOVD (R6)(R14), R15 // copy 8 bytes at a time
MOVD R15, (R3)(R14) // shrVU processes bytes only forwards
ADD $8, R14
CMP R14, R7 // More 8 bytes left?
BLT repeat
done:
MOVD R0, c+56(FP)
RET
// func mulAddVWW(z, x []Word, y, r Word) (c Word)
TEXT ·mulAddVWW(SB), NOSPLIT, $0
MOVD z+0(FP), R10 // R10 = z[]
MOVD x+24(FP), R8 // R8 = x[]
MOVD y+48(FP), R9 // R9 = y
MOVD r+56(FP), R4 // R4 = r = c
MOVD z_len+8(FP), R11 // R11 = z_len
CMP R0, R11
BEQ done
MOVD 0(R8), R20
ADD $-1, R11
MULLD R9, R20, R6 // R6 = z0 = Low-order(x[i]*y)
MULHDU R9, R20, R7 // R7 = z1 = High-order(x[i]*y)
ADDC R4, R6 // R6 = z0 + r
ADDZE R7 // R7 = z1 + CA
CMP R0, R11
MOVD R7, R4 // R4 = c
MOVD R6, 0(R10) // z[i]
BEQ done
// We will read 4 elements per iteration
SRD $2, R11, R14 // R14 = z_len/4
DCBT (R8)
CMP R0, R14
MOVD R14, CTR // Set up the loop counter
BEQ tail // If R9 = 0, we can't use the loop
loop:
MOVD 8(R8), R20 // R20 = x[i]
MOVD 16(R8), R21 // R21 = x[i+1]
MOVD 24(R8), R22 // R22 = x[i+2]
MOVDU 32(R8), R23 // R23 = x[i+3]
MULLD R9, R20, R24 // R24 = z0[i]
MULHDU R9, R20, R20 // R20 = z1[i]
ADDC R4, R24 // R24 = z0[i] + c
ADDZE R20 // R7 = z1[i] + CA
MULLD R9, R21, R25
MULHDU R9, R21, R21
ADDC R20, R25
ADDZE R21
MULLD R9, R22, R26
MULHDU R9, R22, R22
MULLD R9, R23, R27
MULHDU R9, R23, R23
ADDC R21, R26
ADDZE R22
MOVD R24, 8(R10) // z[i]
MOVD R25, 16(R10) // z[i+1]
ADDC R22, R27
ADDZE R23,R4 // update carry
MOVD R26, 24(R10) // z[i+2]
MOVDU R27, 32(R10) // z[i+3]
ADD $-4, R11 // R11 = z_len - 4
BC 16, 0, loop // bdnz
// We may have some elements to read
CMP R0, R11
BEQ done
// Process the remaining elements, one at a time
tail:
MOVDU 8(R8), R20 // R20 = x[i]
MULLD R9, R20, R24 // R24 = z0[i]
MULHDU R9, R20, R25 // R25 = z1[i]
ADD $-1, R11 // R11 = z_len - 1
ADDC R4, R24
ADDZE R25
MOVDU R24, 8(R10) // z[i]
CMP R0, R11
MOVD R25, R4 // R4 = c
BEQ done // If R11 = 0, we are done
MOVDU 8(R8), R20
MULLD R9, R20, R24
MULHDU R9, R20, R25
ADD $-1, R11
ADDC R4, R24
ADDZE R25
MOVDU R24, 8(R10)
CMP R0, R11
MOVD R25, R4
BEQ done
MOVD 8(R8), R20
MULLD R9, R20, R24
MULHDU R9, R20, R25
ADD $-1, R11
ADDC R4, R24
ADDZE R25
MOVD R24, 8(R10)
MOVD R25, R4
done:
MOVD R4, c+64(FP)
RET
// func addMulVVW(z, x []Word, y Word) (c Word)
TEXT ·addMulVVW(SB), NOSPLIT, $0
MOVD z+0(FP), R10 // R10 = z[]
MOVD x+24(FP), R8 // R8 = x[]
MOVD y+48(FP), R9 // R9 = y
MOVD z_len+8(FP), R22 // R22 = z_len
MOVD R0, R3 // R3 will be the index register
CMP R0, R22
MOVD R0, R4 // R4 = c = 0
MOVD R22, CTR // Initialize loop counter
BEQ done
loop:
MOVD (R8)(R3), R20 // Load x[i]
MOVD (R10)(R3), R21 // Load z[i]
MULLD R9, R20, R6 // R6 = Low-order(x[i]*y)
MULHDU R9, R20, R7 // R7 = High-order(x[i]*y)
ADDC R21, R6 // R6 = z0
ADDZE R7 // R7 = z1
ADDC R4, R6 // R6 = z0 + c + 0
ADDZE R7, R4 // c += z1
MOVD R6, (R10)(R3) // Store z[i]
ADD $8, R3
BC 16, 0, loop // bdnz
done:
MOVD R4, c+56(FP)
RET
Zerion Mini Shell 1.0