memclr_mips64x.s

Documentation: runtime

     1// Copyright 2015 The Go Authors. All rights reserved.
     2// Use of this source code is governed by a BSD-style
     3// license that can be found in the LICENSE file.
     4
     5//go:build mips64 || mips64le
     6
     7#include "go_asm.h"
     8#include "textflag.h"
     9
    10// See memclrNoHeapPointers Go doc for important implementation constraints.
    11
    12// func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
    13TEXT runtime·memclrNoHeapPointers(SB),NOSPLIT,$0-16
    14	MOVV	ptr+0(FP), R1
    15	MOVV	n+8(FP), R2
    16	ADDV	R1, R2, R4
    17
    18	// if less than 16 bytes or no MSA, do words check
    19	SGTU	$16, R2, R3
    20	BNE	R3, no_msa
    21	MOVBU	internal∕cpu·MIPS64X+const_offsetMIPS64XHasMSA(SB), R3
    22	BEQ	R3, R0, no_msa
    23
    24	VMOVB	$0, W0
    25
    26	SGTU	$128, R2, R3
    27	BEQ	R3, msa_large
    28
    29	AND	$15, R2, R5
    30	XOR	R2, R5, R6
    31	ADDVU	R1, R6
    32
    33msa_small:
    34	VMOVB	W0, (R1)
    35	ADDVU	$16, R1
    36	SGTU	R6, R1, R3
    37	BNE	R3, R0, msa_small
    38	BEQ	R5, R0, done
    39	VMOVB	W0, -16(R4)
    40	JMP	done
    41
    42msa_large:
    43	AND	$127, R2, R5
    44	XOR	R2, R5, R6
    45	ADDVU	R1, R6
    46
    47msa_large_loop:
    48	VMOVB	W0, (R1)
    49	VMOVB	W0, 16(R1)
    50	VMOVB	W0, 32(R1)
    51	VMOVB	W0, 48(R1)
    52	VMOVB	W0, 64(R1)
    53	VMOVB	W0, 80(R1)
    54	VMOVB	W0, 96(R1)
    55	VMOVB	W0, 112(R1)
    56
    57	ADDVU	$128, R1
    58	SGTU	R6, R1, R3
    59	BNE	R3, R0, msa_large_loop
    60	BEQ	R5, R0, done
    61	VMOVB	W0, -128(R4)
    62	VMOVB	W0, -112(R4)
    63	VMOVB	W0, -96(R4)
    64	VMOVB	W0, -80(R4)
    65	VMOVB	W0, -64(R4)
    66	VMOVB	W0, -48(R4)
    67	VMOVB	W0, -32(R4)
    68	VMOVB	W0, -16(R4)
    69	JMP	done
    70
    71no_msa:
    72	// if less than 8 bytes, do one byte at a time
    73	SGTU	$8, R2, R3
    74	BNE	R3, out
    75
    76	// do one byte at a time until 8-aligned
    77	AND	$7, R1, R3
    78	BEQ	R3, words
    79	MOVB	R0, (R1)
    80	ADDV	$1, R1
    81	JMP	-4(PC)
    82
    83words:
    84	// do 8 bytes at a time if there is room
    85	ADDV	$-7, R4, R2
    86
    87	SGTU	R2, R1, R3
    88	BEQ	R3, out
    89	MOVV	R0, (R1)
    90	ADDV	$8, R1
    91	JMP	-4(PC)
    92
    93out:
    94	BEQ	R1, R4, done
    95	MOVB	R0, (R1)
    96	ADDV	$1, R1
    97	JMP	-3(PC)
    98done:
    99	RET
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