aboutsummaryrefslogtreecommitdiff
path: root/gcc/config/rs6000/linux-unwind.h
diff options
context:
space:
mode:
Diffstat (limited to 'gcc/config/rs6000/linux-unwind.h')
-rw-r--r--gcc/config/rs6000/linux-unwind.h324
1 files changed, 324 insertions, 0 deletions
diff --git a/gcc/config/rs6000/linux-unwind.h b/gcc/config/rs6000/linux-unwind.h
new file mode 100644
index 00000000000..1acf738123e
--- /dev/null
+++ b/gcc/config/rs6000/linux-unwind.h
@@ -0,0 +1,324 @@
+/* DWARF2 EH unwinding support for PowerPC and PowerPC64 Linux.
+ Copyright (C) 2004, 2005 Free Software Foundation, Inc.
+
+ This file is part of GCC.
+
+ GCC is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 2, or (at your
+ option) any later version.
+
+ In addition to the permissions in the GNU General Public License,
+ the Free Software Foundation gives you unlimited permission to link
+ the compiled version of this file with other programs, and to
+ distribute those programs without any restriction coming from the
+ use of this file. (The General Public License restrictions do
+ apply in other respects; for example, they cover modification of
+ the file, and distribution when not linked into another program.)
+
+ GCC is distributed in the hope that it will be useful, but WITHOUT
+ ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+ License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GCC; see the file COPYING. If not, write to the
+ Free Software Foundation, 59 Temple Place - Suite 330, Boston,
+ MA 02111-1307, USA. */
+
+/* This file defines our own versions of various kernel and user
+ structs, so that system headers are not needed, which otherwise
+ can make bootstrapping a new toolchain difficult. Do not use
+ these structs elsewhere; Many fields are missing, particularly
+ from the end of the structures. */
+
+struct gcc_vregs
+{
+ __attribute__ ((vector_size (16))) int vr[32];
+#ifdef __powerpc64__
+ unsigned int pad1[3];
+ unsigned int vscr;
+ unsigned int vsave;
+ unsigned int pad2[3];
+#else
+ unsigned int vsave;
+ unsigned int pad[2];
+ unsigned int vscr;
+#endif
+};
+
+struct gcc_regs
+{
+ unsigned long gpr[32];
+ unsigned long nip;
+ unsigned long msr;
+ unsigned long orig_gpr3;
+ unsigned long ctr;
+ unsigned long link;
+ unsigned long xer;
+ unsigned long ccr;
+ unsigned long softe;
+ unsigned long trap;
+ unsigned long dar;
+ unsigned long dsisr;
+ unsigned long result;
+ unsigned long pad1[4];
+ double fpr[32];
+ unsigned int pad2;
+ unsigned int fpscr;
+#ifdef __powerpc64__
+ struct gcc_vregs *vp;
+#else
+ unsigned int pad3[2];
+#endif
+ struct gcc_vregs vregs;
+};
+
+struct gcc_ucontext
+{
+#ifdef __powerpc64__
+ unsigned long pad[28];
+#else
+ unsigned long pad[12];
+#endif
+ struct gcc_regs *regs;
+ struct gcc_regs rsave;
+};
+
+#ifdef __powerpc64__
+
+enum { SIGNAL_FRAMESIZE = 128 };
+
+/* If the current unwind info (FS) does not contain explicit info
+ saving R2, then we have to do a minor amount of code reading to
+ figure out if it was saved. The big problem here is that the
+ code that does the save/restore is generated by the linker, so
+ we have no good way to determine at compile time what to do. */
+
+#define MD_FROB_UPDATE_CONTEXT frob_update_context
+
+static void
+frob_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
+{
+ if (fs->regs.reg[2].how == REG_UNSAVED)
+ {
+ unsigned int *insn
+ = (unsigned int *) _Unwind_GetGR (context, LINK_REGISTER_REGNUM);
+ if (*insn == 0xE8410028)
+ _Unwind_SetGRPtr (context, 2, context->cfa + 40);
+ }
+}
+
+/* If PC is at a sigreturn trampoline, return a pointer to the
+ regs. Otherwise return NULL. */
+
+static struct gcc_regs *
+get_regs (struct _Unwind_Context *context)
+{
+ const unsigned char *pc = context->ra;
+
+ /* addi r1, r1, 128; li r0, 0x0077; sc (sigreturn) */
+ /* addi r1, r1, 128; li r0, 0x00AC; sc (rt_sigreturn) */
+ if (*(unsigned int *) (pc + 0) != 0x38210000 + SIGNAL_FRAMESIZE
+ || *(unsigned int *) (pc + 8) != 0x44000002)
+ return NULL;
+ if (*(unsigned int *) (pc + 4) == 0x38000077)
+ {
+ struct sigframe {
+ char gap[SIGNAL_FRAMESIZE];
+ unsigned long pad[7];
+ struct gcc_regs *regs;
+ } *frame = (struct sigframe *) context->cfa;
+ return frame->regs;
+ }
+ else if (*(unsigned int *) (pc + 4) == 0x380000AC)
+ {
+ /* This works for 2.4 kernels, but not for 2.6 kernels with vdso
+ because pc isn't pointing into the stack. Can be removed when
+ no one is running 2.4.19 or 2.4.20, the first two ppc64
+ kernels released. */
+ struct rt_sigframe_24 {
+ int tramp[6];
+ void *pinfo;
+ struct gcc_ucontext *puc;
+ } *frame24 = (struct rt_sigframe_24 *) pc;
+
+ /* Test for magic value in *puc of vdso. */
+ if ((long) frame24->puc != -21 * 8)
+ return frame24->puc->regs;
+ else
+ {
+ /* This works for 2.4.21 and later kernels. */
+ struct rt_sigframe {
+ char gap[SIGNAL_FRAMESIZE];
+ struct gcc_ucontext uc;
+ unsigned long pad[2];
+ int tramp[6];
+ void *pinfo;
+ struct gcc_ucontext *puc;
+ } *frame = (struct rt_sigframe *) context->cfa;
+ return frame->uc.regs;
+ }
+ }
+ return NULL;
+}
+
+#else /* !__powerpc64__ */
+
+enum { SIGNAL_FRAMESIZE = 64 };
+
+static struct gcc_regs *
+get_regs (struct _Unwind_Context *context)
+{
+ const unsigned char *pc = context->ra;
+
+ /* li r0, 0x7777; sc (sigreturn old) */
+ /* li r0, 0x0077; sc (sigreturn new) */
+ /* li r0, 0x6666; sc (rt_sigreturn old) */
+ /* li r0, 0x00AC; sc (rt_sigreturn new) */
+ if (*(unsigned int *) (pc + 4) != 0x44000002)
+ return NULL;
+ if (*(unsigned int *) (pc + 0) == 0x38007777
+ || *(unsigned int *) (pc + 0) == 0x38000077)
+ {
+ struct sigframe {
+ char gap[SIGNAL_FRAMESIZE];
+ unsigned long pad[7];
+ struct gcc_regs *regs;
+ } *frame = (struct sigframe *) context->cfa;
+ return frame->regs;
+ }
+ else if (*(unsigned int *) (pc + 0) == 0x38006666
+ || *(unsigned int *) (pc + 0) == 0x380000AC)
+ {
+ struct rt_sigframe {
+ char gap[SIGNAL_FRAMESIZE + 16];
+ char siginfo[128];
+ struct gcc_ucontext uc;
+ } *frame = (struct rt_sigframe *) context->cfa;
+ return frame->uc.regs;
+ }
+ return NULL;
+}
+#endif
+
+/* Find an entry in the process auxiliary vector. The canonical way to
+ test for VMX is to look at AT_HWCAP. */
+
+static long
+ppc_linux_aux_vector (long which)
+{
+ /* __libc_stack_end holds the original stack passed to a process. */
+ extern long *__libc_stack_end;
+ long argc;
+ char **argv;
+ char **envp;
+ struct auxv
+ {
+ long a_type;
+ long a_val;
+ } *auxp;
+
+ /* The Linux kernel puts argc first on the stack. */
+ argc = __libc_stack_end[0];
+ /* Followed by argv, NULL terminated. */
+ argv = (char **) __libc_stack_end + 1;
+ /* Followed by environment string pointers, NULL terminated. */
+ envp = argv + argc + 1;
+ while (*envp++)
+ continue;
+ /* Followed by the aux vector, zero terminated. */
+ for (auxp = (struct auxv *) envp; auxp->a_type != 0; ++auxp)
+ if (auxp->a_type == which)
+ return auxp->a_val;
+ return 0;
+}
+
+/* Do code reading to identify a signal frame, and set the frame
+ state data appropriately. See unwind-dw2.c for the structs. */
+
+#define MD_FALLBACK_FRAME_STATE_FOR ppc_fallback_frame_state
+
+static _Unwind_Reason_Code
+ppc_fallback_frame_state (struct _Unwind_Context *context,
+ _Unwind_FrameState *fs)
+{
+ static long hwcap = 0;
+ struct gcc_regs *regs = get_regs (context);
+ long new_cfa;
+ int i;
+
+ if (regs == NULL)
+ return _URC_END_OF_STACK;
+
+ new_cfa = regs->gpr[STACK_POINTER_REGNUM];
+ fs->cfa_how = CFA_REG_OFFSET;
+ fs->cfa_reg = STACK_POINTER_REGNUM;
+ fs->cfa_offset = new_cfa - (long) context->cfa;
+
+ for (i = 0; i < 32; i++)
+ if (i != STACK_POINTER_REGNUM)
+ {
+ fs->regs.reg[i].how = REG_SAVED_OFFSET;
+ fs->regs.reg[i].loc.offset = (long) &regs->gpr[i] - new_cfa;
+ }
+
+ fs->regs.reg[CR2_REGNO].how = REG_SAVED_OFFSET;
+ fs->regs.reg[CR2_REGNO].loc.offset = (long) &regs->ccr - new_cfa;
+
+ fs->regs.reg[LINK_REGISTER_REGNUM].how = REG_SAVED_OFFSET;
+ fs->regs.reg[LINK_REGISTER_REGNUM].loc.offset = (long) &regs->link - new_cfa;
+
+ fs->regs.reg[ARG_POINTER_REGNUM].how = REG_SAVED_OFFSET;
+ fs->regs.reg[ARG_POINTER_REGNUM].loc.offset = (long) &regs->nip - new_cfa;
+ fs->retaddr_column = ARG_POINTER_REGNUM;
+
+ if (hwcap == 0)
+ {
+ hwcap = ppc_linux_aux_vector (16);
+ /* These will already be set if we found AT_HWCAP. A non-zero
+ value stops us looking again if for some reason we couldn't
+ find AT_HWCAP. */
+#ifdef __powerpc64__
+ hwcap |= 0xc0000000;
+#else
+ hwcap |= 0x80000000;
+#endif
+ }
+
+ /* If we have a FPU... */
+ if (hwcap & 0x08000000)
+ for (i = 0; i < 32; i++)
+ {
+ fs->regs.reg[i + 32].how = REG_SAVED_OFFSET;
+ fs->regs.reg[i + 32].loc.offset = (long) &regs->fpr[i] - new_cfa;
+ }
+
+ /* If we have a VMX unit... */
+ if (hwcap & 0x10000000)
+ {
+ struct gcc_vregs *vregs;
+#ifdef __powerpc64__
+ vregs = regs->vp;
+#else
+ vregs = &regs->vregs;
+#endif
+ if (regs->msr & (1 << 25))
+ {
+ for (i = 0; i < 32; i++)
+ {
+ fs->regs.reg[i + FIRST_ALTIVEC_REGNO].how = REG_SAVED_OFFSET;
+ fs->regs.reg[i + FIRST_ALTIVEC_REGNO].loc.offset
+ = (long) &vregs[i] - new_cfa;
+ }
+
+ fs->regs.reg[VSCR_REGNO].how = REG_SAVED_OFFSET;
+ fs->regs.reg[VSCR_REGNO].loc.offset = (long) &vregs->vscr - new_cfa;
+ }
+
+ fs->regs.reg[VRSAVE_REGNO].how = REG_SAVED_OFFSET;
+ fs->regs.reg[VRSAVE_REGNO].loc.offset = (long) &vregs->vsave - new_cfa;
+ }
+
+ return _URC_NO_REASON;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-19 11:46:08 +0000