summaryrefslogtreecommitdiffstats
path: root/js/src/jit/GenerateAtomicOperations.py
diff options
context:
space:
mode:
Diffstat (limited to 'js/src/jit/GenerateAtomicOperations.py')
-rw-r--r--js/src/jit/GenerateAtomicOperations.py873
1 files changed, 873 insertions, 0 deletions
diff --git a/js/src/jit/GenerateAtomicOperations.py b/js/src/jit/GenerateAtomicOperations.py
new file mode 100644
index 0000000000..24b5a191cf
--- /dev/null
+++ b/js/src/jit/GenerateAtomicOperations.py
@@ -0,0 +1,873 @@
+# 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
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# 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["CPU_ARCH"]
+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 barrier:
+ insns += fmt_insn("mfence")
+ 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]")
+ if barrier:
+ insns += fmt_insn("mfence")
+ 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 barrier:
+ insns += fmt_insn("dmb ish")
+ 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 barrier:
+ insns += fmt_insn("dmb sy")
+ 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 barrier:
+ insns += fmt_insn("mfence")
+ 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_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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#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")
+
+ # 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.
+ # See bug 1756347.
+ 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,
+ }
+ )