| // 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) |
| |
| #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). |
| |
| PCALIGN $16 |
| 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). |
| |
| PCALIGN $16 |
| 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 |
| PCALIGN $16 |
| |
| 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. |
| |
| PCALIGN $16 |
| 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] |
| PCALIGN $16 |
| 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 |
| PCALIGN $16 |
| |
| 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 |
| PCALIGN $16 |
| |
| 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 |
| |
| |
