summaryrefslogtreecommitdiff
path: root/arch/mips
AgeCommit message (Collapse)AuthorLines
2012-11-05fix numerous mips abi constant definition mismatchesRich Felker-89/+120
2012-10-18better support for reverse-endian variants of arm/mips/microblazeRich Felker-0/+4
these macros are supported by more compilers
2012-10-18floating point environment/exceptions support for mipsRich Felker-3/+13
2012-10-15add support for TLS variant I, presently needed for arm and mipsRich Felker-4/+19
despite documentation that makes it sound a lot different, the only ABI-constraint difference between TLS variants II and I seems to be that variant II stores the initial TLS segment immediately below the thread pointer (i.e. the thread pointer points to the end of it) and variant I stores the initial TLS segment above the thread pointer, requiring the thread descriptor to be stored below. the actual value stored in the thread pointer register also tends to have per-arch random offsets applied to it for silly micro-optimization purposes. with these changes applied, TLS should be basically working on all supported archs except microblaze. I'm still working on getting the necessary information and a working toolchain that can build TLS binaries for microblaze, but in theory, static-linked programs with TLS and dynamic-linked programs where only the main executable uses TLS should already work on microblaze. alignment constraints have not yet been heavily tested, so it's possible that this code does not always align TLS segments correctly on archs that need TLS variant I.
2012-10-04dynamic-linked TLS support for everything but dlopen'd libsRich Felker-1/+5
currently, only i386 is tested. x86_64 and arm should probably work. the necessary relocation types for mips and microblaze have not been added because I don't understand how they're supposed to work, and I'm not even sure if it's defined yet on microblaze. I may be able to reverse engineer the requirements out of gcc/binutils output.
2012-09-22fix broken semctl on systems that don't use IPC_64 flagRich Felker-0/+2
not tested on mips and arm; they may still be broken. x86_64 should be ok now.
2012-09-15add O_EXEC open modeRich Felker-0/+1
the linux O_PATH mode provides the necessary semantics for both the O_SEARCH and O_EXEC modes defined and required by POSIX 2008.
2012-09-15fix buggy constraints in mips inline syscall asmRich Felker-2/+2
if same register is used for input/output, the compiler must be told. otherwise is generates random junk code that clobbers the result. in pure syscall-wrapper functions, nothing went wrong, but in more complex functions where register allocation is non-trivial, things broke badly.
2012-09-13add O_PATH/O_SEARCH support to fcntl.hRich Felker-0/+2
I'm not 100% sure that Linux's O_PATH meets the POSIX requirements for O_SEARCH, but it seems very close if not perfect. and old kernels ignore it, so O_SEARCH will still work as desired as long as the caller has read permissions to the directory.
2012-09-11improve mips syscall asm constraints to use immediates, if possibleRich Felker-12/+21
by using the "ir" constraint (immediate or register) and the carefully constructed instruction addu $2,$0,%2 which can take either an immediate or a register for %2, the new inline asm admits maximal optimization with no register spillage to the stack when the compiler successfully performs constant propagration, but still works by allocating a register when the syscall number cannot be recognized as a constant. in the case of syscalls with 0-3 arguments it barely matters, but for 4-argument syscalls, using an immediate for the syscall number avoids creating a stack frame for the syscall wrapper function.
2012-09-10eliminate assumption that mips syscall restart preserves r25Rich Felker-23/+12
all past and current kernel versions have done so, but there seems to be no reason it's necessary and the sentiment from everyone I've asked has been that we should not rely on it. instead, use r7 (an argument register) which will necessarily be preserved upon syscall restart. however this only works for 0-3 argument syscalls, and we have to resort to the function call for 4-argument syscalls.
2012-09-09inline syscall support for mipsRich Felker-0/+57
this drastically reduces the size of some functions which are purely syscall wrappers. disabled for clang due to known bugs satisfying register constraints.
2012-09-08syscall organization overhaulRich Felker-87/+41
now public syscall.h only exposes __NR_* and SYS_* constants and the variadic syscall function. no macros or inline functions, no __syscall_ret or other internal details, no 16-/32-bit legacy syscall renaming, etc. this logic has all been moved to src/internal/syscall.h with the arch-specific parts in arch/$(ARCH)/syscall_arch.h, and the amount of arch-specific stuff has been reduced to a minimum. changes still need to be reviewed/double-checked. minimal testing on i386 and mips has already been performed.
2012-09-07add clang-compatible thread-pointer code for mipsRich Felker-0/+4
clang does not presently support the "v" constraint we want to use to get the result from $3, and trying to use register...__asm__("$3") to do the same invokes serious compiler bugs. so for now, i'm working around the issue with an extra temp register and putting $3 in the clobber list instead of using it as output. when the bugs in clang are fixed, this issue should be revisited to generate smaller/faster code like what gcc gets.
2012-09-02avoid "inline" in public headers for strict c89 compatibilityRich Felker-7/+7
while musl itself requires a c99 compiler, some applications insist on being compiled with c89 compilers, and use of "inline" in the headers was breaking them. much of this had been avoided already by just skipping the inline keyword in pre-c99 compilers or modes, but this new unified solution is cleaner and may/should result in better code generation in the default gcc configuration.
2012-08-11avoid need for -march=mips2 to compile mips atomic.h asmRich Felker-0/+8
linux guarantees ll/sc are always available. on mips1, they will be emulated by the kernel. thus they are part of the linux mips1 abi and safe to use.
2012-08-10fix incorrect ptrdiff_t type on mipsRich Felker-1/+1
2012-08-09add defines for number of sigset_t bytes syscalls expectRich Felker-0/+2
yet another gratuitous mips incompatibility...
2012-08-07further fixes for mips ioctl.h headerRich Felker-4/+4
untested; hopefully it's right now
2012-08-07fix another mips gratuitous-incompatibility bug: ioctl numbersRich Felker-2/+2
2012-08-05fix socket.h on mipsRich Felker-0/+3
why does mips have to be gratuitously incompatible in every possible imaginable way?
2012-08-05more stuff lost committing mips dynamic linkerRich Felker-2/+2
2012-08-05mips dynamic linker supportRich Felker-3/+53
not heavily tested, but the basics are working. the basic concept is that the dynamic linker entry point code invokes a pure-PIC (no global accesses) C function in reloc.h to perform the early GOT relocations needed to make the dynamic linker itself functional, then invokes __dynlink like on other archs. since mips uses some ugly arch-specific hacks to optimize relocating the GOT (rather than just using the normal DT_REL[A] tables like on other archs), the dynamic linker has been modified slightly to support calling arch-specific relocation code in reloc.h. most of the actual mips-specific behavior was developed by reading the output of readelf on libc.so and simple executable files. i could not find good reference information on which relocation types need to be supported or their semantics, so it's possible that some legitimate usage cases will not work yet.
2012-07-22add floating point register saving/restoring to mips setjmp/longjmpRich Felker-1/+1
also fix the alignment of jmp_buf to meet the abi. linux always emulates fpu on mips if it's not present, so enabling this code unconditionally is "safe" but may be slow. in the long term it may be preferable to find a way to disable it on soft float builds.
2012-07-12fix broken mips a_fetch_addRich Felker-7/+7
sc was overwriting the result
2012-07-12mipsel (little endian) supportRich Felker-1/+1
the fields in the mcontext_t are long long (for no good reason) even on 32-bit mips, so the offset of the instruction pointer (as a word) varies depending on endianness.
2012-07-12workaround another sendmsg kernel bug on 64-bit machinesRich Felker-0/+7
the kernel wrongly expects the cmsg length field to be size_t instead of socklen_t. in order to work around the issue, we have to impose a length limit and copy to a local buffer. the length limit should be more than sufficient for any real-world use; these headers are only used for passing file descriptors and permissions between processes over unix sockets.
2012-07-12fix redef of sigprocmask constants on mipsRich Felker-0/+3
this fix is easier than trying to reorder the header stuff
2012-07-12more mips bits-header fixesRich Felker-2/+6
signal handling was very broken because of this
2012-07-12fix mips syscalls with long long argsRich Felker-1/+1
like arm, mips requires 64-bit arguments to be "aligned" on an even register boundary.
2012-07-12fix mips mcontext_t structure sizeRich Felker-1/+5
otherwise offs in ucontext_t will be wrong, and break code that inspects or modifies the signal makes (including cancellation code).
2012-07-11fix MAP_ANONYMOUS value for mips, remove cruft copied from i386Rich Felker-2/+1
2012-07-11initial version of mips (o32) port, based on work by Richard Pennington (rdp)Rich Felker-0/+2037
basically, this version of the code was obtained by starting with rdp's work from his ellcc source tree, adapting it to musl's build system and coding style, auditing the bits headers for discrepencies with kernel definitions or glibc/LSB ABI or large file issues, fixing up incompatibility with the old binutils from aboriginal linux, and adding some new special cases to deal with the oddities of sigaction and pipe syscall interfaces on mips. at present, minimal test programs work, but some interfaces are broken or missing. threaded programs probably will not link.