Add support for more Linux architectures (#904)

* Add support for alpha

* Add support for hppa

* Add support for ia64

* Add support for sh

Author: glaubitz

absl/base/internal/direct_mmap.h

@@ -74,7 +74,8 @@ namespace base_internal {
 inline void* DirectMmap(void* start, size_t length, int prot, int flags, int fd,
                         off64_t offset) noexcept {
 #if defined(__i386__) || defined(__ARM_ARCH_3__) || defined(__ARM_EABI__) || \
-    defined(__m68k__) ||                                                     \
+    defined(__m68k__) || defined(__sh__) ||                                  \
+    (defined(__hppa__) && !defined(__LP64__)) ||                             \
     (defined(__mips__) && _MIPS_SIM == _MIPS_SIM_ABI32) ||                   \
     (defined(__PPC__) && !defined(__PPC64__)) ||                             \
     (defined(__riscv) && __riscv_xlen == 32) ||                              \

absl/debugging/internal/examine_stack.cc

@@ -46,11 +46,17 @@ void* GetProgramCounter(void* vuc) {
     ucontext_t* context = reinterpret_cast<ucontext_t*>(vuc);
 #if defined(__aarch64__)
     return reinterpret_cast<void*>(context->uc_mcontext.pc);
+#elif defined(__alpha__)
+    return reinterpret_cast<void*>(context->uc_mcontext.sc_pc);
 #elif defined(__arm__)
     return reinterpret_cast<void*>(context->uc_mcontext.arm_pc);
+#elif defined(__hppa__)
+    return reinterpret_cast<void*>(context->uc_mcontext.sc_iaoq[0]);
 #elif defined(__i386__)
     if (14 < ABSL_ARRAYSIZE(context->uc_mcontext.gregs))
       return reinterpret_cast<void*>(context->uc_mcontext.gregs[14]);
+#elif defined(__ia64__)
+    return reinterpret_cast<void*>(context->uc_mcontext.sc_ip);
 #elif defined(__m68k__)
     return reinterpret_cast<void*>(context->uc_mcontext.gregs[16]);
 #elif defined(__mips__)
@@ -65,6 +71,8 @@ void* GetProgramCounter(void* vuc) {
     return reinterpret_cast<void*>(context->uc_mcontext.psw.addr & 0x7fffffff);
 #elif defined(__s390__) && defined(__s390x__)
     return reinterpret_cast<void*>(context->uc_mcontext.psw.addr);
+#elif defined(__sh__)
+    return reinterpret_cast<void*>(context->uc_mcontext.pc);
 #elif defined(__sparc__) && !defined(__arch64__)
     return reinterpret_cast<void*>(context->uc_mcontext.gregs[19]);
 #elif defined(__sparc__) && defined(__arch64__)