authorgravatar for benjamin.feng@glassdoor.comBenjamin Feng <benjamin.feng@glassdoor.com> 2021-04-08 23:10:42-05:00
committergravatar for benjamin.feng@glassdoor.comBenjamin Feng <benjamin.feng@glassdoor.com> 2021-04-10 22:47:22-05:00
logb409accc9657ec1afcb6f38bbbcdc0e218244f13
tree48551febffa6f6702a84d50bd3babdfb52c6334a
parentdf910b33f4edd11e8cb15cd75e4f22e123417285

Copy over ppc clone from musl


1 files changed, 65 insertions(+), 0 deletions(-)

lib/std/special/c.zig+65
......@@ -491,6 +491,71 @@ fn clone() callconv(.Naked) void {
491491 \\ syscall
492492 );
493493 },
494 .powerpc => {
495 // __clone(func, stack, flags, arg, ptid, tls, ctid)
496 // 3, 4, 5, 6, 7, 8, 9
497
498 // syscall(SYS_clone, flags, stack, ptid, tls, ctid)
499 // 0 3, 4, 5, 6, 7
500 asm volatile (
501 \\# store non-volatile regs r30, r31 on stack in order to put our
502 \\# start func and its arg there
503 \\stwu 30, -16(1)
504 \\stw 31, 4(1)
505 \\
506 \\# save r3 (func) into r30, and r6(arg) into r31
507 \\mr 30, 3
508 \\mr 31, 6
509 \\
510 \\# create initial stack frame for new thread
511 \\clrrwi 4, 4, 4
512 \\li 0, 0
513 \\stwu 0, -16(4)
514 \\
515 \\#move c into first arg
516 \\mr 3, 5
517 \\#mr 4, 4
518 \\mr 5, 7
519 \\mr 6, 8
520 \\mr 7, 9
521 \\
522 \\# move syscall number into r0
523 \\li 0, 120
524 \\
525 \\sc
526 \\
527 \\# check for syscall error
528 \\bns+ 1f # jump to label 1 if no summary overflow.
529 \\#else
530 \\neg 3, 3 #negate the result (errno)
531 \\1:
532 \\# compare sc result with 0
533 \\cmpwi cr7, 3, 0
534 \\
535 \\# if not 0, jump to end
536 \\bne cr7, 2f
537 \\
538 \\#else: we're the child
539 \\#call funcptr: move arg (d) into r3
540 \\mr 3, 31
541 \\#move r30 (funcptr) into CTR reg
542 \\mtctr 30
543 \\# call CTR reg
544 \\bctrl
545 \\# mov SYS_exit into r0 (the exit param is already in r3)
546 \\li 0, 1
547 \\sc
548 \\
549 \\2:
550 \\
551 \\# restore stack
552 \\lwz 30, 0(1)
553 \\lwz 31, 4(1)
554 \\addi 1, 1, 16
555 \\
556 \\blr
557 );
558 },
494559 .powerpc64, .powerpc64le => {
495560 // __clone(func, stack, flags, arg, ptid, tls, ctid)
496561 // 3, 4, 5, 6, 7, 8, 9