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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# This script generates jit/AtomicOperationsGenerated.h
#
# See the big comment in jit/AtomicOperations.h for an explanation.
import buildconfig
is_64bit = "JS_64BIT" in buildconfig.defines
cpu_arch = buildconfig.substs["TARGET_CPU"]
is_gcc = buildconfig.substs["CC_TYPE"] == "gcc"
def fmt_insn(s):
return '"' + s + '\\n\\t"\n'
def gen_seqcst(fun_name):
if cpu_arch in ("x86", "x86_64"):
return r"""
INLINE_ATTR void %(fun_name)s() {
asm volatile ("mfence\n\t" ::: "memory");
}""" % {
"fun_name": fun_name,
}
if cpu_arch == "aarch64":
return r"""
INLINE_ATTR void %(fun_name)s() {
asm volatile ("dmb ish\n\t" ::: "memory");
}""" % {
"fun_name": fun_name,
}
if cpu_arch == "arm":
return r"""
INLINE_ATTR void %(fun_name)s() {
asm volatile ("dmb sy\n\t" ::: "memory");
}""" % {
"fun_name": fun_name,
}
raise Exception("Unexpected arch")
def gen_load(fun_name, cpp_type, size, barrier):
# NOTE: the assembly code must match the generated code in:
# - CacheIRCompiler::emitAtomicsLoadResult
# - LIRGenerator::visitLoadUnboxedScalar
# - CodeGenerator::visitAtomicLoad64 (on 64-bit platforms)
# - MacroAssembler::wasmLoad
if cpu_arch in ("x86", "x86_64"):
insns = ""
if size == 8:
insns += fmt_insn("movb (%[arg]), %[res]")
elif size == 16:
insns += fmt_insn("movw (%[arg]), %[res]")
elif size == 32:
insns += fmt_insn("movl (%[arg]), %[res]")
else:
assert size == 64
insns += fmt_insn("movq (%[arg]), %[res]")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(const %(cpp_type)s* arg) {
%(cpp_type)s res;
asm volatile (%(insns)s
: [res] "=r" (res)
: [arg] "r" (arg)
: "memory");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "aarch64":
insns = ""
if size == 8:
insns += fmt_insn("ldrb %w[res], [%x[arg]]")
elif size == 16:
insns += fmt_insn("ldrh %w[res], [%x[arg]]")
elif size == 32:
insns += fmt_insn("ldr %w[res], [%x[arg]]")
else:
assert size == 64
insns += fmt_insn("ldr %x[res], [%x[arg]]")
if barrier:
insns += fmt_insn("dmb ish")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(const %(cpp_type)s* arg) {
%(cpp_type)s res;
asm volatile (%(insns)s
: [res] "=r" (res)
: [arg] "r" (arg)
: "memory");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "arm":
insns = ""
if size == 8:
insns += fmt_insn("ldrb %[res], [%[arg]]")
elif size == 16:
insns += fmt_insn("ldrh %[res], [%[arg]]")
else:
assert size == 32
insns += fmt_insn("ldr %[res], [%[arg]]")
if barrier:
insns += fmt_insn("dmb sy")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(const %(cpp_type)s* arg) {
%(cpp_type)s res;
asm volatile (%(insns)s
: [res] "=r" (res)
: [arg] "r" (arg)
: "memory");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
raise Exception("Unexpected arch")
def gen_store(fun_name, cpp_type, size, barrier):
# NOTE: the assembly code must match the generated code in:
# - CacheIRCompiler::emitAtomicsStoreResult
# - LIRGenerator::visitStoreUnboxedScalar
# - CodeGenerator::visitAtomicStore64 (on 64-bit platforms)
# - MacroAssembler::wasmStore
if cpu_arch in ("x86", "x86_64"):
insns = ""
if size == 8:
insns += fmt_insn("movb %[val], (%[addr])")
elif size == 16:
insns += fmt_insn("movw %[val], (%[addr])")
elif size == 32:
insns += fmt_insn("movl %[val], (%[addr])")
else:
assert size == 64
insns += fmt_insn("movq %[val], (%[addr])")
if barrier:
insns += fmt_insn("mfence")
return """
INLINE_ATTR void %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
asm volatile (%(insns)s
:
: [addr] "r" (addr), [val] "r"(val)
: "memory");
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "aarch64":
insns = ""
if barrier:
insns += fmt_insn("dmb ish")
if size == 8:
insns += fmt_insn("strb %w[val], [%x[addr]]")
elif size == 16:
insns += fmt_insn("strh %w[val], [%x[addr]]")
elif size == 32:
insns += fmt_insn("str %w[val], [%x[addr]]")
else:
assert size == 64
insns += fmt_insn("str %x[val], [%x[addr]]")
if barrier:
insns += fmt_insn("dmb ish")
return """
INLINE_ATTR void %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
asm volatile (%(insns)s
:
: [addr] "r" (addr), [val] "r"(val)
: "memory");
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "arm":
insns = ""
if barrier:
insns += fmt_insn("dmb sy")
if size == 8:
insns += fmt_insn("strb %[val], [%[addr]]")
elif size == 16:
insns += fmt_insn("strh %[val], [%[addr]]")
else:
assert size == 32
insns += fmt_insn("str %[val], [%[addr]]")
if barrier:
insns += fmt_insn("dmb sy")
return """
INLINE_ATTR void %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
asm volatile (%(insns)s
:
: [addr] "r" (addr), [val] "r"(val)
: "memory");
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
raise Exception("Unexpected arch")
def gen_exchange(fun_name, cpp_type, size):
# NOTE: the assembly code must match the generated code in:
# - MacroAssembler::atomicExchange
# - MacroAssembler::atomicExchange64 (on 64-bit platforms)
if cpu_arch in ("x86", "x86_64"):
# Request an input/output register for `val` so that we can simply XCHG it
# with *addr.
insns = ""
if size == 8:
insns += fmt_insn("xchgb %[val], (%[addr])")
elif size == 16:
insns += fmt_insn("xchgw %[val], (%[addr])")
elif size == 32:
insns += fmt_insn("xchgl %[val], (%[addr])")
else:
assert size == 64
insns += fmt_insn("xchgq %[val], (%[addr])")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
asm volatile (%(insns)s
: [val] "+r" (val)
: [addr] "r" (addr)
: "memory");
return val;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "aarch64":
insns = ""
insns += fmt_insn("dmb ish")
insns += fmt_insn("0:")
if size == 8:
insns += fmt_insn("ldxrb %w[res], [%x[addr]]")
insns += fmt_insn("stxrb %w[scratch], %w[val], [%x[addr]]")
elif size == 16:
insns += fmt_insn("ldxrh %w[res], [%x[addr]]")
insns += fmt_insn("stxrh %w[scratch], %w[val], [%x[addr]]")
elif size == 32:
insns += fmt_insn("ldxr %w[res], [%x[addr]]")
insns += fmt_insn("stxr %w[scratch], %w[val], [%x[addr]]")
else:
assert size == 64
insns += fmt_insn("ldxr %x[res], [%x[addr]]")
insns += fmt_insn("stxr %w[scratch], %x[val], [%x[addr]]")
insns += fmt_insn("cbnz %w[scratch], 0b")
insns += fmt_insn("dmb ish")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
%(cpp_type)s res;
uint32_t scratch;
asm volatile (%(insns)s
: [res] "=&r"(res), [scratch] "=&r"(scratch)
: [addr] "r" (addr), [val] "r"(val)
: "memory", "cc");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "arm":
insns = ""
insns += fmt_insn("dmb sy")
insns += fmt_insn("0:")
if size == 8:
insns += fmt_insn("ldrexb %[res], [%[addr]]")
insns += fmt_insn("strexb %[scratch], %[val], [%[addr]]")
elif size == 16:
insns += fmt_insn("ldrexh %[res], [%[addr]]")
insns += fmt_insn("strexh %[scratch], %[val], [%[addr]]")
else:
assert size == 32
insns += fmt_insn("ldrex %[res], [%[addr]]")
insns += fmt_insn("strex %[scratch], %[val], [%[addr]]")
insns += fmt_insn("cmp %[scratch], #1")
insns += fmt_insn("beq 0b")
insns += fmt_insn("dmb sy")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
%(cpp_type)s res;
uint32_t scratch;
asm volatile (%(insns)s
: [res] "=&r"(res), [scratch] "=&r"(scratch)
: [addr] "r" (addr), [val] "r"(val)
: "memory", "cc");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
raise Exception("Unexpected arch")
def gen_cmpxchg(fun_name, cpp_type, size):
# NOTE: the assembly code must match the generated code in:
# - MacroAssembler::compareExchange
# - MacroAssembler::compareExchange64
if cpu_arch == "x86" and size == 64:
# Use a +A constraint to load `oldval` into EDX:EAX as input/output.
# `newval` is loaded into ECX:EBX.
return r"""
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr,
%(cpp_type)s oldval,
%(cpp_type)s newval) {
asm volatile ("lock; cmpxchg8b (%%[addr])\n\t"
: "+A" (oldval)
: [addr] "r" (addr),
"b" (uint32_t(newval & 0xffff'ffff)),
"c" (uint32_t(newval >> 32))
: "memory", "cc");
return oldval;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
}
if cpu_arch == "arm" and size == 64:
return r"""
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr,
%(cpp_type)s oldval,
%(cpp_type)s newval) {
uint32_t oldval0 = oldval & 0xffff'ffff;
uint32_t oldval1 = oldval >> 32;
uint32_t newval0 = newval & 0xffff'ffff;
uint32_t newval1 = newval >> 32;
asm volatile (
"dmb sy\n\t"
"0: ldrexd r0, r1, [%%[addr]]\n\t"
"cmp r0, %%[oldval0]\n\t"
"bne 1f\n\t"
"cmp r1, %%[oldval1]\n\t"
"bne 1f\n\t"
"mov r2, %%[newval0]\n\t"
"mov r3, %%[newval1]\n\t"
"strexd r4, r2, r3, [%%[addr]]\n\t"
"cmp r4, #1\n\t"
"beq 0b\n\t"
"1: dmb sy\n\t"
"mov %%[oldval0], r0\n\t"
"mov %%[oldval1], r1\n\t"
: [oldval0] "+&r" (oldval0), [oldval1] "+&r"(oldval1)
: [addr] "r" (addr), [newval0] "r" (newval0), [newval1] "r" (newval1)
: "memory", "cc", "r0", "r1", "r2", "r3", "r4");
return uint64_t(oldval0) | (uint64_t(oldval1) << 32);
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
}
if cpu_arch in ("x86", "x86_64"):
# Use a +a constraint to load `oldval` into RAX as input/output register.
insns = ""
if size == 8:
insns += fmt_insn("lock; cmpxchgb %[newval], (%[addr])")
elif size == 16:
insns += fmt_insn("lock; cmpxchgw %[newval], (%[addr])")
elif size == 32:
insns += fmt_insn("lock; cmpxchgl %[newval], (%[addr])")
else:
assert size == 64
insns += fmt_insn("lock; cmpxchgq %[newval], (%[addr])")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr,
%(cpp_type)s oldval,
%(cpp_type)s newval) {
asm volatile (%(insns)s
: [oldval] "+a" (oldval)
: [addr] "r" (addr), [newval] "r" (newval)
: "memory", "cc");
return oldval;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "aarch64":
insns = ""
insns += fmt_insn("dmb ish")
insns += fmt_insn("0:")
if size == 8:
insns += fmt_insn("uxtb %w[scratch], %w[oldval]")
insns += fmt_insn("ldxrb %w[res], [%x[addr]]")
insns += fmt_insn("cmp %w[res], %w[scratch]")
insns += fmt_insn("b.ne 1f")
insns += fmt_insn("stxrb %w[scratch], %w[newval], [%x[addr]]")
elif size == 16:
insns += fmt_insn("uxth %w[scratch], %w[oldval]")
insns += fmt_insn("ldxrh %w[res], [%x[addr]]")
insns += fmt_insn("cmp %w[res], %w[scratch]")
insns += fmt_insn("b.ne 1f")
insns += fmt_insn("stxrh %w[scratch], %w[newval], [%x[addr]]")
elif size == 32:
insns += fmt_insn("mov %w[scratch], %w[oldval]")
insns += fmt_insn("ldxr %w[res], [%x[addr]]")
insns += fmt_insn("cmp %w[res], %w[scratch]")
insns += fmt_insn("b.ne 1f")
insns += fmt_insn("stxr %w[scratch], %w[newval], [%x[addr]]")
else:
assert size == 64
insns += fmt_insn("mov %x[scratch], %x[oldval]")
insns += fmt_insn("ldxr %x[res], [%x[addr]]")
insns += fmt_insn("cmp %x[res], %x[scratch]")
insns += fmt_insn("b.ne 1f")
insns += fmt_insn("stxr %w[scratch], %x[newval], [%x[addr]]")
insns += fmt_insn("cbnz %w[scratch], 0b")
insns += fmt_insn("1: dmb ish")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr,
%(cpp_type)s oldval,
%(cpp_type)s newval) {
%(cpp_type)s res, scratch;
asm volatile (%(insns)s
: [res] "=&r" (res), [scratch] "=&r" (scratch)
: [addr] "r" (addr), [oldval] "r"(oldval), [newval] "r" (newval)
: "memory", "cc");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "arm":
insns = ""
insns += fmt_insn("dmb sy")
insns += fmt_insn("0:")
if size == 8:
insns += fmt_insn("uxtb %[scratch], %[oldval]")
insns += fmt_insn("ldrexb %[res], [%[addr]]")
insns += fmt_insn("cmp %[res], %[scratch]")
insns += fmt_insn("bne 1f")
insns += fmt_insn("strexb %[scratch], %[newval], [%[addr]]")
elif size == 16:
insns += fmt_insn("uxth %[scratch], %[oldval]")
insns += fmt_insn("ldrexh %[res], [%[addr]]")
insns += fmt_insn("cmp %[res], %[scratch]")
insns += fmt_insn("bne 1f")
insns += fmt_insn("strexh %[scratch], %[newval], [%[addr]]")
else:
assert size == 32
insns += fmt_insn("mov %[scratch], %[oldval]")
insns += fmt_insn("ldrex %[res], [%[addr]]")
insns += fmt_insn("cmp %[res], %[scratch]")
insns += fmt_insn("bne 1f")
insns += fmt_insn("strex %[scratch], %[newval], [%[addr]]")
insns += fmt_insn("cmp %[scratch], #1")
insns += fmt_insn("beq 0b")
insns += fmt_insn("1: dmb sy")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr,
%(cpp_type)s oldval,
%(cpp_type)s newval) {
%(cpp_type)s res, scratch;
asm volatile (%(insns)s
: [res] "=&r" (res), [scratch] "=&r" (scratch)
: [addr] "r" (addr), [oldval] "r"(oldval), [newval] "r" (newval)
: "memory", "cc");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
raise Exception("Unexpected arch")
def gen_fetchop(fun_name, cpp_type, size, op):
# NOTE: the assembly code must match the generated code in:
# - MacroAssembler::atomicFetchOp
# - MacroAssembler::atomicFetchOp64 (on 64-bit platforms)
if cpu_arch in ("x86", "x86_64"):
# The `add` operation can be optimized with XADD.
if op == "add":
insns = ""
if size == 8:
insns += fmt_insn("lock; xaddb %[val], (%[addr])")
elif size == 16:
insns += fmt_insn("lock; xaddw %[val], (%[addr])")
elif size == 32:
insns += fmt_insn("lock; xaddl %[val], (%[addr])")
else:
assert size == 64
insns += fmt_insn("lock; xaddq %[val], (%[addr])")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
asm volatile (%(insns)s
: [val] "+&r" (val)
: [addr] "r" (addr)
: "memory", "cc");
return val;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
# Use a +a constraint to ensure `res` is stored in RAX. This is required
# for the CMPXCHG instruction.
insns = ""
if size == 8:
insns += fmt_insn("movb (%[addr]), %[res]")
insns += fmt_insn("0: movb %[res], %[scratch]")
insns += fmt_insn("OPb %[val], %[scratch]")
insns += fmt_insn("lock; cmpxchgb %[scratch], (%[addr])")
elif size == 16:
insns += fmt_insn("movw (%[addr]), %[res]")
insns += fmt_insn("0: movw %[res], %[scratch]")
insns += fmt_insn("OPw %[val], %[scratch]")
insns += fmt_insn("lock; cmpxchgw %[scratch], (%[addr])")
elif size == 32:
insns += fmt_insn("movl (%[addr]), %[res]")
insns += fmt_insn("0: movl %[res], %[scratch]")
insns += fmt_insn("OPl %[val], %[scratch]")
insns += fmt_insn("lock; cmpxchgl %[scratch], (%[addr])")
else:
assert size == 64
insns += fmt_insn("movq (%[addr]), %[res]")
insns += fmt_insn("0: movq %[res], %[scratch]")
insns += fmt_insn("OPq %[val], %[scratch]")
insns += fmt_insn("lock; cmpxchgq %[scratch], (%[addr])")
insns = insns.replace("OP", op)
insns += fmt_insn("jnz 0b")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
%(cpp_type)s res, scratch;
asm volatile (%(insns)s
: [res] "=&a" (res), [scratch] "=&r" (scratch)
: [addr] "r" (addr), [val] "r"(val)
: "memory", "cc");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "aarch64":
insns = ""
insns += fmt_insn("dmb ish")
insns += fmt_insn("0:")
if size == 8:
insns += fmt_insn("ldxrb %w[res], [%x[addr]]")
insns += fmt_insn("OP %x[scratch1], %x[res], %x[val]")
insns += fmt_insn("stxrb %w[scratch2], %w[scratch1], [%x[addr]]")
elif size == 16:
insns += fmt_insn("ldxrh %w[res], [%x[addr]]")
insns += fmt_insn("OP %x[scratch1], %x[res], %x[val]")
insns += fmt_insn("stxrh %w[scratch2], %w[scratch1], [%x[addr]]")
elif size == 32:
insns += fmt_insn("ldxr %w[res], [%x[addr]]")
insns += fmt_insn("OP %x[scratch1], %x[res], %x[val]")
insns += fmt_insn("stxr %w[scratch2], %w[scratch1], [%x[addr]]")
else:
assert size == 64
insns += fmt_insn("ldxr %x[res], [%x[addr]]")
insns += fmt_insn("OP %x[scratch1], %x[res], %x[val]")
insns += fmt_insn("stxr %w[scratch2], %x[scratch1], [%x[addr]]")
cpu_op = op
if cpu_op == "or":
cpu_op = "orr"
if cpu_op == "xor":
cpu_op = "eor"
insns = insns.replace("OP", cpu_op)
insns += fmt_insn("cbnz %w[scratch2], 0b")
insns += fmt_insn("dmb ish")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
%(cpp_type)s res;
uintptr_t scratch1, scratch2;
asm volatile (%(insns)s
: [res] "=&r" (res), [scratch1] "=&r" (scratch1), [scratch2] "=&r"(scratch2)
: [addr] "r" (addr), [val] "r"(val)
: "memory", "cc");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
if cpu_arch == "arm":
insns = ""
insns += fmt_insn("dmb sy")
insns += fmt_insn("0:")
if size == 8:
insns += fmt_insn("ldrexb %[res], [%[addr]]")
insns += fmt_insn("OP %[scratch1], %[res], %[val]")
insns += fmt_insn("strexb %[scratch2], %[scratch1], [%[addr]]")
elif size == 16:
insns += fmt_insn("ldrexh %[res], [%[addr]]")
insns += fmt_insn("OP %[scratch1], %[res], %[val]")
insns += fmt_insn("strexh %[scratch2], %[scratch1], [%[addr]]")
else:
assert size == 32
insns += fmt_insn("ldrex %[res], [%[addr]]")
insns += fmt_insn("OP %[scratch1], %[res], %[val]")
insns += fmt_insn("strex %[scratch2], %[scratch1], [%[addr]]")
cpu_op = op
if cpu_op == "or":
cpu_op = "orr"
if cpu_op == "xor":
cpu_op = "eor"
insns = insns.replace("OP", cpu_op)
insns += fmt_insn("cmp %[scratch2], #1")
insns += fmt_insn("beq 0b")
insns += fmt_insn("dmb sy")
return """
INLINE_ATTR %(cpp_type)s %(fun_name)s(%(cpp_type)s* addr, %(cpp_type)s val) {
%(cpp_type)s res;
uintptr_t scratch1, scratch2;
asm volatile (%(insns)s
: [res] "=&r" (res), [scratch1] "=&r" (scratch1), [scratch2] "=&r"(scratch2)
: [addr] "r" (addr), [val] "r"(val)
: "memory", "cc");
return res;
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
raise Exception("Unexpected arch")
def gen_pause(fun_name):
if cpu_arch in ("x86", "x86_64"):
return r"""
INLINE_ATTR void %(fun_name)s() {
asm volatile ("pause" :::);
}""" % {
"fun_name": fun_name,
}
if cpu_arch == "aarch64":
return r"""
INLINE_ATTR void %(fun_name)s() {
asm volatile ("isb" ::: "memory");
}""" % {
"fun_name": fun_name,
}
if cpu_arch == "arm":
return r"""
INLINE_ATTR void %(fun_name)s() {
asm volatile ("yield" :::);
}""" % {
"fun_name": fun_name,
}
raise Exception("Unexpected arch")
def gen_copy(fun_name, cpp_type, size, unroll, direction):
assert direction in ("down", "up")
offset = 0
if direction == "up":
offset = unroll - 1
insns = ""
for i in range(unroll):
if cpu_arch in ("x86", "x86_64"):
if size == 1:
insns += fmt_insn("movb OFFSET(%[src]), %[scratch]")
insns += fmt_insn("movb %[scratch], OFFSET(%[dst])")
elif size == 4:
insns += fmt_insn("movl OFFSET(%[src]), %[scratch]")
insns += fmt_insn("movl %[scratch], OFFSET(%[dst])")
else:
assert size == 8
insns += fmt_insn("movq OFFSET(%[src]), %[scratch]")
insns += fmt_insn("movq %[scratch], OFFSET(%[dst])")
elif cpu_arch == "aarch64":
if size == 1:
insns += fmt_insn("ldrb %w[scratch], [%x[src], OFFSET]")
insns += fmt_insn("strb %w[scratch], [%x[dst], OFFSET]")
else:
assert size == 8
insns += fmt_insn("ldr %x[scratch], [%x[src], OFFSET]")
insns += fmt_insn("str %x[scratch], [%x[dst], OFFSET]")
elif cpu_arch == "arm":
if size == 1:
insns += fmt_insn("ldrb %[scratch], [%[src], #OFFSET]")
insns += fmt_insn("strb %[scratch], [%[dst], #OFFSET]")
else:
assert size == 4
insns += fmt_insn("ldr %[scratch], [%[src], #OFFSET]")
insns += fmt_insn("str %[scratch], [%[dst], #OFFSET]")
else:
raise Exception("Unexpected arch")
insns = insns.replace("OFFSET", str(offset * size))
if direction == "down":
offset += 1
else:
offset -= 1
return """
INLINE_ATTR void %(fun_name)s(uint8_t* dst, const uint8_t* src) {
%(cpp_type)s* dst_ = reinterpret_cast<%(cpp_type)s*>(dst);
const %(cpp_type)s* src_ = reinterpret_cast<const %(cpp_type)s*>(src);
%(cpp_type)s scratch;
asm volatile (%(insns)s
: [scratch] "=&r" (scratch)
: [dst] "r" (dst_), [src] "r"(src_)
: "memory");
}""" % {
"cpp_type": cpp_type,
"fun_name": fun_name,
"insns": insns,
}
HEADER_TEMPLATE = """\
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef jit_AtomicOperationsGenerated_h
#define jit_AtomicOperationsGenerated_h
/* This file is generated by jit/GenerateAtomicOperations.py. Do not edit! */
#include "mozilla/Attributes.h"
namespace js {
namespace jit {
%(contents)s
} // namespace jit
} // namespace js
#endif // jit_AtomicOperationsGenerated_h
"""
def generate_atomics_header(c_out):
contents = ""
if cpu_arch in ("x86", "x86_64", "aarch64") or (
cpu_arch == "arm" and int(buildconfig.substs["ARM_ARCH"]) >= 7
):
contents += "#define JS_HAVE_GENERATED_ATOMIC_OPS 1"
# `fence` performs a full memory barrier.
contents += gen_seqcst("AtomicFenceSeqCst")
contents += gen_load("AtomicLoad8SeqCst", "uint8_t", 8, True)
contents += gen_load("AtomicLoad16SeqCst", "uint16_t", 16, True)
contents += gen_load("AtomicLoad32SeqCst", "uint32_t", 32, True)
if is_64bit:
contents += gen_load("AtomicLoad64SeqCst", "uint64_t", 64, True)
# These are access-atomic up to sizeof(uintptr_t).
contents += gen_load("AtomicLoad8Unsynchronized", "uint8_t", 8, False)
contents += gen_load("AtomicLoad16Unsynchronized", "uint16_t", 16, False)
contents += gen_load("AtomicLoad32Unsynchronized", "uint32_t", 32, False)
if is_64bit:
contents += gen_load("AtomicLoad64Unsynchronized", "uint64_t", 64, False)
contents += gen_store("AtomicStore8SeqCst", "uint8_t", 8, True)
contents += gen_store("AtomicStore16SeqCst", "uint16_t", 16, True)
contents += gen_store("AtomicStore32SeqCst", "uint32_t", 32, True)
if is_64bit:
contents += gen_store("AtomicStore64SeqCst", "uint64_t", 64, True)
# These are access-atomic up to sizeof(uintptr_t).
contents += gen_store("AtomicStore8Unsynchronized", "uint8_t", 8, False)
contents += gen_store("AtomicStore16Unsynchronized", "uint16_t", 16, False)
contents += gen_store("AtomicStore32Unsynchronized", "uint32_t", 32, False)
if is_64bit:
contents += gen_store("AtomicStore64Unsynchronized", "uint64_t", 64, False)
# `exchange` takes a cell address and a value. It stores it in the cell and
# returns the value previously in the cell.
contents += gen_exchange("AtomicExchange8SeqCst", "uint8_t", 8)
contents += gen_exchange("AtomicExchange16SeqCst", "uint16_t", 16)
contents += gen_exchange("AtomicExchange32SeqCst", "uint32_t", 32)
if is_64bit:
contents += gen_exchange("AtomicExchange64SeqCst", "uint64_t", 64)
# `cmpxchg` takes a cell address, an expected value and a replacement value.
# If the value in the cell equals the expected value then the replacement value
# is stored in the cell. It always returns the value previously in the cell.
contents += gen_cmpxchg("AtomicCmpXchg8SeqCst", "uint8_t", 8)
contents += gen_cmpxchg("AtomicCmpXchg16SeqCst", "uint16_t", 16)
contents += gen_cmpxchg("AtomicCmpXchg32SeqCst", "uint32_t", 32)
contents += gen_cmpxchg("AtomicCmpXchg64SeqCst", "uint64_t", 64)
# `add` adds a value atomically to the cell and returns the old value in the
# cell. (There is no `sub`; just add the negated value.)
contents += gen_fetchop("AtomicAdd8SeqCst", "uint8_t", 8, "add")
contents += gen_fetchop("AtomicAdd16SeqCst", "uint16_t", 16, "add")
contents += gen_fetchop("AtomicAdd32SeqCst", "uint32_t", 32, "add")
if is_64bit:
contents += gen_fetchop("AtomicAdd64SeqCst", "uint64_t", 64, "add")
# `and` bitwise-ands a value atomically into the cell and returns the old value
# in the cell.
contents += gen_fetchop("AtomicAnd8SeqCst", "uint8_t", 8, "and")
contents += gen_fetchop("AtomicAnd16SeqCst", "uint16_t", 16, "and")
contents += gen_fetchop("AtomicAnd32SeqCst", "uint32_t", 32, "and")
if is_64bit:
contents += gen_fetchop("AtomicAnd64SeqCst", "uint64_t", 64, "and")
# `or` bitwise-ors a value atomically into the cell and returns the old value
# in the cell.
contents += gen_fetchop("AtomicOr8SeqCst", "uint8_t", 8, "or")
contents += gen_fetchop("AtomicOr16SeqCst", "uint16_t", 16, "or")
contents += gen_fetchop("AtomicOr32SeqCst", "uint32_t", 32, "or")
if is_64bit:
contents += gen_fetchop("AtomicOr64SeqCst", "uint64_t", 64, "or")
# `xor` bitwise-xors a value atomically into the cell and returns the old value
# in the cell.
contents += gen_fetchop("AtomicXor8SeqCst", "uint8_t", 8, "xor")
contents += gen_fetchop("AtomicXor16SeqCst", "uint16_t", 16, "xor")
contents += gen_fetchop("AtomicXor32SeqCst", "uint32_t", 32, "xor")
if is_64bit:
contents += gen_fetchop("AtomicXor64SeqCst", "uint64_t", 64, "xor")
# Pause or yield instruction.
contents += gen_pause("AtomicPause")
# See comment in jit/AtomicOperations-shared-jit.cpp for an explanation.
wordsize = 8 if is_64bit else 4
words_in_block = 8
blocksize = words_in_block * wordsize
contents += gen_copy(
"AtomicCopyUnalignedBlockDownUnsynchronized",
"uint8_t",
1,
blocksize,
"down",
)
contents += gen_copy(
"AtomicCopyUnalignedBlockUpUnsynchronized", "uint8_t", 1, blocksize, "up"
)
contents += gen_copy(
"AtomicCopyUnalignedWordDownUnsynchronized", "uint8_t", 1, wordsize, "down"
)
contents += gen_copy(
"AtomicCopyUnalignedWordUpUnsynchronized", "uint8_t", 1, wordsize, "up"
)
contents += gen_copy(
"AtomicCopyBlockDownUnsynchronized",
"uintptr_t",
wordsize,
words_in_block,
"down",
)
contents += gen_copy(
"AtomicCopyBlockUpUnsynchronized",
"uintptr_t",
wordsize,
words_in_block,
"up",
)
contents += gen_copy(
"AtomicCopyWordUnsynchronized", "uintptr_t", wordsize, 1, "down"
)
contents += gen_copy("AtomicCopyByteUnsynchronized", "uint8_t", 1, 1, "down")
contents += "\n"
contents += (
"constexpr size_t JS_GENERATED_ATOMICS_BLOCKSIZE = "
+ str(blocksize)
+ ";\n"
)
contents += (
"constexpr size_t JS_GENERATED_ATOMICS_WORDSIZE = " + str(wordsize) + ";\n"
)
# Work around a GCC issue on 32-bit x86 by adding MOZ_NEVER_INLINE.
if is_gcc and cpu_arch == "x86":
contents = contents.replace("INLINE_ATTR", "MOZ_NEVER_INLINE inline")
else:
contents = contents.replace("INLINE_ATTR", "inline")
c_out.write(
HEADER_TEMPLATE
% {
"contents": contents,
}
)