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// GREGS_OFFSET = 184
// REGISTER_SIZE = 8
// SIMD_REGISTER_SIZE = 16
std::arch::global_asm! {
".text",
".global crash_context_getcontext",
".hidden crash_context_getcontext",
".type crash_context_getcontext, #function",
".align 4",
".cfi_startproc",
"crash_context_getcontext:",
// The saved context will return to the getcontext() call point
// with a return value of 0
"str xzr, [x0, 184]", // GREGS_OFFSET
"stp x18, x19, [x0, 328]", // GREGS_OFFSET + 18 * REGISTER_SIZE
"stp x20, x21, [x0, 344]", // GREGS_OFFSET + 20 * REGISTER_SIZE
"stp x22, x23, [x0, 360]", // GREGS_OFFSET + 22 * REGISTER_SIZE
"stp x24, x25, [x0, 376]", // GREGS_OFFSET + 24 * REGISTER_SIZE
"stp x26, x27, [x0, 392]", // GREGS_OFFSET + 26 * REGISTER_SIZE
"stp x28, x29, [x0, 408]", // GREGS_OFFSET + 28 * REGISTER_SIZE
"str x30, [x0, 424]", // GREGS_OFFSET + 30 * REGISTER_SIZE
// Place LR into the saved PC, this will ensure that when switching to this
// saved context with setcontext() control will pass back to the caller of
// getcontext(), we have already arranged to return the appropriate return
// value in x0 above.
"str x30, [x0, 440]",
// Save the current SP
"mov x2, sp",
"str x2, [x0, 432]",
// Initialize the pstate.
"str xzr, [x0, 448]",
// Figure out where to place the first context extension block.
"add x2, x0, #464",
// Write the context extension fpsimd header.
// FPSIMD_MAGIC = 0x46508001
"mov w3, #(0x46508001 & 0xffff)",
"movk w3, #(0x46508001 >> 16), lsl #16",
"str w3, [x2, #0]", // FPSIMD_CONTEXT_MAGIC_OFFSET
"mov w3, #528", // FPSIMD_CONTEXT_SIZE
"str w3, [x2, #4]", // FPSIMD_CONTEXT_SIZE_OFFSET
// Fill in the FP SIMD context.
"add x3, x2, #144", // VREGS_OFFSET + 8 * SIMD_REGISTER_SIZE
"stp d8, d9, [x3], #32",
"stp d10, d11, [x3], #32",
"stp d12, d13, [x3], #32",
"stp d14, d15, [x3], #32",
"add x3, x2, 8", // FPSR_OFFSET
"mrs x4, fpsr",
"str w4, [x3]",
"mrs x4, fpcr",
"str w4, [x3, 4]", // FPCR_OFFSET - FPSR_OFFSET
// Write the termination context extension header.
"add x2, x2, #528", // FPSIMD_CONTEXT_SIZE
"str xzr, [x2, #0]", // FPSIMD_CONTEXT_MAGIC_OFFSET
"str xzr, [x2, #4]", // FPSIMD_CONTEXT_SIZE_OFFSET
// Grab the signal mask
// rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8)
"add x2, x0, #40", // UCONTEXT_SIGMASK_OFFSET
"mov x0, #0", // SIG_BLOCK
"mov x1, #0", // NULL
"mov x3, #(64 / 8)", // _NSIG / 8
"mov x8, #135", // __NR_rt_sigprocmask
"svc 0",
// Return x0 for success
"mov x0, 0",
"ret",
".cfi_endproc",
".size crash_context_getcontext, . - crash_context_getcontext",
}