Re: [PATCH v4] libgo: Don't use pt_regs member in mcontext_t

[Ian Lance Taylor via Gcc-patches]

On Mon, Apr 11, 2022 at 11:28 AM Sören Tempel <soe...@soeren-tempel.net> wrote:
>
> Ian Lance Taylor <i...@golang.org> wrote:
> > What I was hoping from my earlier question was that you could tell me
> > the exact lines to write in the current sources that will compile on
> > MUSL. Don't include <asm/ptrace.h>, don't refer to earlier patches as
> > that is what I tried to do earlier but failed, don't add new #define
> > macros, just add #ifdef and appropriate lines.  Thanks.  If the new
> > lines also work on glibc using register indexes rather than names,
> > that would be a bonus.
>
> Sorry, may bad. Here you go:

Thanks!  I tested a version of that code with glibc, and it works
there too, so I've committed this patch after testing on
powerpc-linux-gnu and x86_64-linux-gnu.  Please let me know about any
problems.

Ian

5c66a1182acceebf9fbcf02039d85a53c9c18bf1
diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index f93eaf48e28..75ee2e3aaca 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-45108f37070afb696b069768700e39a269f1fecb
+323ab0e6fab89978bdbd83dca9c2ad9c5dcd690f
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
diff --git a/libgo/runtime/go-signal.c b/libgo/runtime/go-signal.c
index 9c919e1568a..2caddd068d6 100644
--- a/libgo/runtime/go-signal.c
+++ b/libgo/runtime/go-signal.c
@@ -230,15 +230,10 @@ getSiginfo(siginfo_t *info, void *context 
__attribute__((unused)))
        ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.gregs[REG_EIP];
 #elif defined(__alpha__) && defined(__linux__)
        ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.sc_pc;
+#elif defined(__PPC64__) && defined(__linux__)
+       ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.gp_regs[32];
 #elif defined(__PPC__) && defined(__linux__)
-       // For some reason different libc implementations use
-       // different names.
-#if defined(__PPC64__) || defined(__GLIBC__)
-       ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.regs->nip;
-#else
-       // Assumed to be ppc32 musl.
        ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.gregs[32];
-#endif
 #elif defined(__PPC__) && defined(_AIX)
        ret.sigpc = ((ucontext_t*)(context))->uc_mcontext.jmp_context.iar;
 #elif defined(__aarch64__) && defined(__linux__)
@@ -354,15 +349,15 @@ dumpregs(siginfo_t *info __attribute__((unused)), void 
*context __attribute__((u
                mcontext_t *m = &((ucontext_t*)(context))->uc_mcontext;
                int i;
 
-#if defined(__PPC64__) || defined(__GLIBC__)
+#if defined(__PPC64__)
                for (i = 0; i < 32; i++)
-                       runtime_printf("r%d %X\n", i, m->regs->gpr[i]);
-               runtime_printf("pc  %X\n", m->regs->nip);
-               runtime_printf("msr %X\n", m->regs->msr);
-               runtime_printf("cr  %X\n", m->regs->ccr);
-               runtime_printf("lr  %X\n", m->regs->link);
-               runtime_printf("ctr %X\n", m->regs->ctr);
-               runtime_printf("xer %X\n", m->regs->xer);
+                       runtime_printf("r%d %X\n", i, m->gp_regs[i]);
+               runtime_printf("pc  %X\n", m->gp_regs[32]);
+               runtime_printf("msr %X\n", m->gp_regs[33]);
+               runtime_printf("cr  %X\n", m->gp_regs[38]);
+               runtime_printf("lr  %X\n", m->gp_regs[36]);
+               runtime_printf("ctr %X\n", m->gp_regs[35]);
+               runtime_printf("xer %X\n", m->gp_regs[37]);
 #else
                for (i = 0; i < 32; i++)
                        runtime_printf("r%d %X\n", i, m->gregs[i]);