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musl/arch/mips/pthread_arch.h

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initial version of mips (o32) port, based on work by Richard Pennington (rdp) 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.
2012-07-11 08:22:13 +00:00
static inline struct pthread *__pthread_self()
{
add clang-compatible thread-pointer code for mips 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.
2012-09-07 16:18:14 +00:00
#ifdef __clang__
add support for TLS variant I, presently needed for arm and mips 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.
2012-10-15 22:51:53 +00:00
char *tp;
__asm__ __volatile__ (".word 0x7c03e83b ; move %0, $3" : "=r" (tp) : : "$3" );
add clang-compatible thread-pointer code for mips 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.
2012-09-07 16:18:14 +00:00
#else
add support for TLS variant I, presently needed for arm and mips 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.
2012-10-15 22:51:53 +00:00
register char *tp __asm__("$3");
__asm__ __volatile__ (".word 0x7c03e83b" : "=r" (tp) );
add clang-compatible thread-pointer code for mips 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.
2012-09-07 16:18:14 +00:00
#endif
add support for TLS variant I, presently needed for arm and mips 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.
2012-10-15 22:51:53 +00:00
return (pthread_t)(tp - 0x7000 - sizeof(struct pthread));
initial version of mips (o32) port, based on work by Richard Pennington (rdp) 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.
2012-07-11 08:22:13 +00:00
}
add support for TLS variant I, presently needed for arm and mips 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.
2012-10-15 22:51:53 +00:00
#define TLS_ABOVE_TP
#define TP_ADJ(p) ((char *)(p) + sizeof(struct pthread) + 0x7000)
mipsel (little endian) support 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.
2012-07-13 01:49:30 +00:00
#define CANCEL_REG_IP (3-(union {int __i; char __b;}){1}.__b)