[MIPS] compiler-rt: Fix stat struct's size for O32 ABI

[raj.khem]

Summary

stat struct size differs on glibc based on ABI choices e.g. 64bit off_t
and/or 64bit time_t will make this size different. Therefore separate
out the O32 case out, makes it more readable.

[MaskRay]

Is mips o32 still worth spending efforts? For mips perhaps we should only care about newer ABIs. Sanitizers are optional features anyway...

[raj.khem]

In D140948#4026982, @MaskRay wrote:

Is mips o32 still worth spending efforts? For mips perhaps we should only care about newer ABIs. Sanitizers are optional features anyway...

o32 is most prevalent mips32 ABI out in the field today (considering 32bit even 64bit mips ), IMO its important to fix o32.

compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.h

 const unsigned struct_kernel_stat64_sz = 104;
 #elif defined(__powerpc__) && !defined(__powerpc64__)
 const unsigned struct_kernel_stat_sz = 72;
 const unsigned struct_kernel_stat64_sz = 104;
 #elif defined(__powerpc64__)
 const unsigned struct_kernel_stat_sz = 144;
 const unsigned struct_kernel_stat64_sz = 104;
 #elif defined(__mips__)
+#if defined(__mips_o32) // O32 ABI
+#if _TIME_BITS == 64
+const unsigned struct_kernel_stat_sz = 112;
+const unsigned struct_kernel_stat64_sz = 112;
+#elif _FILE_OFFSET_BITS == 64
+const unsigned struct_kernel_stat_sz = 160;
+const unsigned struct_kernel_stat64_sz = 160;
+#else
+const unsigned struct_kernel_stat_sz = 144;
+const unsigned struct_kernel_stat64_sz = 160;
+#endif
+#else // __mips_o32
 const unsigned struct_kernel_stat_sz =
     SANITIZER_ANDROID
         ? FIRST_32_SECOND_64(104, 128)
         : FIRST_32_SECOND_64((_MIPS_SIM == _ABIN32) ? 176 : 160, 216);
 const unsigned struct_kernel_stat64_sz = 104;
+#endif
 #elif defined(__s390__) && !defined(__s390x__)
 const unsigned struct_kernel_stat_sz = 64;
 const unsigned struct_kernel_stat64_sz = 104;
 #elif defined(__s390x__)
 const unsigned struct_kernel_stat_sz = 144;
 const unsigned struct_kernel_stat64_sz = 0;
 #elif defined(__sparc__) && defined(__arch64__)
 const unsigned struct___old_kernel_stat_sz = 0;