// Copyright 2014 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 ppc64 ppc64le #include "textflag.h" // func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr) TEXT runtime·memclrNoHeapPointers(SB), NOSPLIT|NOFRAME, $0-16 MOVD ptr+0(FP), R3 MOVD n+8(FP), R4 // Determine if there are doublewords to clear check: ANDCC $7, R4, R5 // R5: leftover bytes to clear SRD $3, R4, R6 // R6: double words to clear CMP R6, $0, CR1 // CR1[EQ] set if no double words BC 12, 6, nozerolarge // only single bytes CMP R4, $512 BLT under512 // special case for < 512 ANDCC $127, R3, R8 // check for 128 alignment of address BEQ zero512setup ANDCC $7, R3, R15 BEQ zero512xsetup // at least 8 byte aligned // zero bytes up to 8 byte alignment ANDCC $1, R3, R15 // check for byte alignment BEQ byte2 MOVB R0, 0(R3) // zero 1 byte ADD $1, R3 // bump ptr by 1 ADD $-1, R4 byte2: ANDCC $2, R3, R15 // check for 2 byte alignment BEQ byte4 MOVH R0, 0(R3) // zero 2 bytes ADD $2, R3 // bump ptr by 2 ADD $-2, R4 byte4: ANDCC $4, R3, R15 // check for 4 byte alignment BEQ zero512xsetup MOVW R0, 0(R3) // zero 4 bytes ADD $4, R3 // bump ptr by 4 ADD $-4, R4 BR zero512xsetup // ptr should now be 8 byte aligned under512: MOVD R6, CTR // R6 = number of double words SRDCC $2, R6, R7 // 32 byte chunks? BNE zero32setup // Clear double words zero8: MOVD R0, 0(R3) // double word ADD $8, R3 ADD $-8, R4 BC 16, 0, zero8 // dec ctr, br zero8 if ctr not 0 BR nozerolarge // handle leftovers // Prepare to clear 32 bytes at a time. zero32setup: DCBTST (R3) // prepare data cache XXLXOR VS32, VS32, VS32 // clear VS32 (V0) MOVD R7, CTR // number of 32 byte chunks MOVD $16, R8 zero32: STXVD2X VS32, (R3+R0) // store 16 bytes STXVD2X VS32, (R3+R8) ADD $32, R3 ADD $-32, R4 BC 16, 0, zero32 // dec ctr, br zero32 if ctr not 0 RLDCLCC $61, R4, $3, R6 // remaining doublewords BEQ nozerolarge MOVD R6, CTR // set up the CTR for doublewords BR zero8 nozerolarge: ANDCC $7, R4, R5 // any remaining bytes BC 4, 1, LR // ble lr zerotail: MOVD R5, CTR // set up to clear tail bytes zerotailloop: MOVB R0, 0(R3) // clear single bytes ADD $1, R3 BC 16, 0, zerotailloop // dec ctr, br zerotailloop if ctr not 0 RET zero512xsetup: // 512 chunk with extra needed ANDCC $8, R3, R11 // 8 byte alignment? BEQ zero512setup16 MOVD R0, 0(R3) // clear 8 bytes ADD $8, R3 // update ptr to next 8 ADD $-8, R4 // dec count by 8 zero512setup16: ANDCC $127, R3, R14 // < 128 byte alignment BEQ zero512setup // handle 128 byte alignment MOVD $128, R15 SUB R14, R15, R14 // find increment to 128 alignment SRD $4, R14, R15 // number of 16 byte chunks zero512presetup: MOVD R15, CTR // loop counter of 16 bytes XXLXOR VS32, VS32, VS32 // clear VS32 (V0) zero512preloop: // clear up to 128 alignment STXVD2X VS32, (R3+R0) // clear 16 bytes ADD $16, R3 // update ptr ADD $-16, R4 // dec count BC 16, 0, zero512preloop zero512setup: // setup for dcbz loop CMP R4, $512 // check if at least 512 BLT remain SRD $9, R4, R8 // loop count for 512 chunks MOVD R8, CTR // set up counter MOVD $128, R9 // index regs for 128 bytes MOVD $256, R10 MOVD $384, R11 zero512: DCBZ (R3+R0) // clear first chunk DCBZ (R3+R9) // clear second chunk DCBZ (R3+R10) // clear third chunk DCBZ (R3+R11) // clear fourth chunk ADD $512, R3 ADD $-512, R4 BC 16, 0, zero512 remain: CMP R4, $128 // check if 128 byte chunks left BLT smaller DCBZ (R3+R0) // clear 128 ADD $128, R3 ADD $-128, R4 BR remain smaller: ANDCC $127, R4, R7 // find leftovers BEQ done CMP R7, $64 // more than 64, do 32 at a time BLT zero8setup // less than 64, do 8 at a time SRD $5, R7, R7 // set up counter for 32 BR zero32setup zero8setup: SRDCC $3, R7, R7 // less than 8 bytes BEQ nozerolarge MOVD R7, CTR BR zero8 done: RET