ppc64.go

     1  // Copyright 2025 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  package asmgen
     6  
     7  var ArchPPC64x = &Arch{
     8  	Name:          "ppc64x",
     9  	Build:         "ppc64 || ppc64le",
    10  	WordBits:      64,
    11  	WordBytes:     8,
    12  	CarrySafeLoop: true,
    13  
    14  	// Note: The old, hand-written ppc64x assembly used MOVDU
    15  	// to avoid explicit pointer updates in a few routines, but the new
    16  	// generated code runs just as fast, so we haven't bothered to try
    17  	// to add that back. (It's not trivial; you'd have to keep the pointers
    18  	// shifted one word in order to make the semantics work.)
    19  	//
    20  	// The old assembly also used some complex vector instructions
    21  	// to implement lshVU and rshVU, but the generated code that uses
    22  	// ordinary integer instructions is much faster than the vector code was,
    23  	// at least on the power10 gomote.
    24  
    25  	regs: []string{
    26  		// R0 is 0 by convention.
    27  		// R1 is SP.
    28  		// R2 is TOC.
    29  		// R30 is g.
    30  		// R31 is the assembler/linker temporary (which we use too).
    31  		"R3", "R4", "R5", "R6", "R7", "R8", "R9",
    32  		"R10", "R11", "R12" /*R13 is TLS*/, "R14", "R15", "R16", "R17", "R18", "R19",
    33  		"R20", "R21", "R22", "R23", "R24", "R25", "R26", "R27", "R28", "R29",
    34  	},
    35  	reg0:   "R0",
    36  	regTmp: "R31",
    37  
    38  	// Note: Could write an addF and subF to use ADDZE and SUBZE,
    39  	// but we have R0 so it doesn't seem to matter much.
    40  
    41  	mov:   "MOVD",
    42  	add:   "ADD",
    43  	adds:  "ADDC",
    44  	adcs:  "ADDE",
    45  	sub:   "SUB",
    46  	subs:  "SUBC",
    47  	sbcs:  "SUBE",
    48  	mul:   "MULLD",
    49  	mulhi: "MULHDU",
    50  	lsh:   "SLD",
    51  	rsh:   "SRD",
    52  	and:   "ANDCC", // regular AND does not accept immediates
    53  	or:    "OR",
    54  	xor:   "XOR",
    55  
    56  	jmpZero:    "CMP %[1]s, $0; BEQ %[2]s",
    57  	jmpNonZero: "CMP %s, $0; BNE %s",
    58  
    59  	// Note: Using CTR means that we could free the count register
    60  	// during the loop body, but the portable logic doesn't know that,
    61  	// and we're not hurting for registers.
    62  	loopTop:    "CMP %[1]s, $0; BEQ %[2]s; MOVD %[1]s, CTR",
    63  	loopBottom: "BDNZ %[2]s",
    64  }
    65
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