libgcc/config/pa/hpux-unwind.h - gcc - Git at Google

 /* DWARF2 EH unwinding support for PA HP-UX.
    Copyright (C) 2005-2021 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 3, or (at your option)
 any later version.

 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.

 Under Section 7 of GPL version 3, you are granted additional
 permissions described in the GCC Runtime Library Exception, version
 3.1, as published by the Free Software Foundation.

 You should have received a copy of the GNU General Public License and
 a copy of the GCC Runtime Library Exception along with this program;
 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 <http://www.gnu.org/licenses/>.  */

 /* Do code reading to identify a signal frame, and set the frame
    state data appropriately.  See unwind-dw2.c for the structs.  */

 /* Don't use this if inhibit_libc is set.
    The build for this target will fail trying to include missing headers. */
 #ifndef inhibit_libc
 #include <signal.h>
 #include <sys/ucontext.h>
 #include <unistd.h>

 /* FIXME: We currently ignore the high halves of general, space and
    control registers on PA 2.0 machines for applications using the
    32-bit runtime.  We don't restore space registers or the floating
    point status registers.  */

 #define MD_FALLBACK_FRAME_STATE_FOR pa_fallback_frame_state

 /* HP-UX 10.X doesn't define GetSSReg.  */
 #ifndef GetSSReg
 #define GetSSReg(ssp, ss_reg) \
   ((UseWideRegs (ssp))							\
    ? (ssp)->ss_wide.ss_32.ss_reg ## _lo					\
    : (ssp)->ss_narrow.ss_reg)
 #endif

 #if TARGET_64BIT
 #define GetSSRegAddr(ssp, ss_reg) ((long) &((ssp)->ss_wide.ss_64.ss_reg))
 #else
 #define GetSSRegAddr(ssp, ss_reg) \
   ((UseWideRegs (ssp))							\
    ? (long) &((ssp)->ss_wide.ss_32.ss_reg ## _lo)			\
    : (long) &((ssp)->ss_narrow.ss_reg))
 #endif

 #define UPDATE_FS_FOR_SAR(FS, N) \
   (FS)->regs.reg[N].how = REG_SAVED_OFFSET;				\
   (FS)->regs.reg[N].loc.offset = GetSSRegAddr (mc, ss_cr11) - new_cfa

 #define UPDATE_FS_FOR_GR(FS, GRN, N) \
   (FS)->regs.reg[N].how = REG_SAVED_OFFSET;				\
   (FS)->regs.reg[N].loc.offset = GetSSRegAddr (mc, ss_gr##GRN) - new_cfa

 #define UPDATE_FS_FOR_FR(FS, FRN, N) \
   (FS)->regs.reg[N].how = REG_SAVED_OFFSET;				\
   (FS)->regs.reg[N].loc.offset = (long) &(mc->ss_fr##FRN) - new_cfa;

 #define UPDATE_FS_FOR_PC(FS, N) \
   (FS)->regs.reg[N].how = REG_SAVED_OFFSET;				\
   (FS)->regs.reg[N].loc.offset = GetSSRegAddr (mc, ss_pcoq_head) - new_cfa

 /* Extract bit field from word using HP's numbering (MSB = 0).  */
 #define GET_FIELD(X, FROM, TO) \
   ((X) >> (31 - (TO)) & ((1 << ((TO) - (FROM) + 1)) - 1))

 static inline int
 sign_extend (int x, int len)
 {
   int signbit = (1 << (len - 1));
   int mask = (signbit << 1) - 1;
   return ((x & mask) ^ signbit) - signbit;
 }

 /* Extract a 17-bit signed constant from branch instructions.  */
 static inline int
 extract_17 (unsigned word)
 {
   return sign_extend (GET_FIELD (word, 19, 28)
 		      | GET_FIELD (word, 29, 29) << 10
 		      | GET_FIELD (word, 11, 15) << 11
 		      | (word & 0x1) << 16, 17);
 }

 /* Extract a 22-bit signed constant from branch instructions.  */
 static inline int
 extract_22 (unsigned word)
 {
   return sign_extend (GET_FIELD (word, 19, 28)
 		      | GET_FIELD (word, 29, 29) << 10
 		      | GET_FIELD (word, 11, 15) << 11
 		      | GET_FIELD (word, 6, 10) << 16
 		      | (word & 0x1) << 21, 22);
 }

 static _Unwind_Reason_Code
 pa_fallback_frame_state (struct _Unwind_Context *context,
 			 _Unwind_FrameState *fs)
 {
   static long cpu;
   unsigned int *pc = (unsigned int *) context->ra;

   if (pc == 0)
     return _URC_END_OF_STACK;

   /* Check for relocation of the return value.  */
   if (!TARGET_64BIT
       && *(pc + 0) == 0x2fd01224		/* fstd,ma fr4,8(sp) */
       && *(pc + 1) == 0x0fd9109d		/* ldw -4(sp),ret1 */
       && *(pc + 2) == 0x0fd130bc)		/* ldw,mb -8(sp),ret0 */
     pc += 3;
   else if (!TARGET_64BIT
 	   && *(pc + 0) == 0x27d01224		/* fstw,ma fr4,8(sp) */
 	   && *(pc + 1) == 0x0fd130bc)		/* ldw,mb -8(sp),ret0 */
     pc += 2;
   else if (!TARGET_64BIT
 	   && *(pc + 0) == 0x0fdc12b0		/* stw,ma ret0,8(sp) */
 	   && *(pc + 1) == 0x0fdd1299		/* stw ret1,-4(sp) */
 	   && *(pc + 2) == 0x2fd13024)		/* fldd,mb -8(sp),fr4 */
     pc += 3;
   else if (!TARGET_64BIT
 	   && *(pc + 0) == 0x0fdc12b0		/* stw,ma ret0,8(sp) */
 	   && *(pc + 1) == 0x27d13024)		/* fldw,mb -8(sp),fr4 */
     pc += 2;

   /* Check if the return address points to an export stub (PA 1.1 or 2.0).  */
   if ((!TARGET_64BIT
        && *(pc + 0) == 0x4bc23fd1		/* ldw -18(sp),rp */
        && *(pc + 1) == 0x004010a1		/* ldsid (rp),r1 */
        && *(pc + 2) == 0x00011820		/* mtsp r1,sr0 */
        && *(pc + 3) == 0xe0400002)		/* be,n 0(sr0,rp) */
       ||
       (!TARGET_64BIT
        && *(pc + 0) == 0x4bc23fd1		/* ldw -18(sp),rp */
        && *(pc + 1) == 0xe840d002))		/* bve,n (rp) */
     {
       fs->regs.cfa_how    = CFA_REG_OFFSET;
       fs->regs.cfa_reg    = 30;
       fs->regs.cfa_offset = 0;

       fs->retaddr_column = 0;
       fs->regs.reg[0].how = REG_SAVED_OFFSET;
       fs->regs.reg[0].loc.offset = -24;

       /* Update context to describe the stub frame.  */
       uw_update_context (context, fs);

       /* Set up fs to describe the FDE for the caller of this stub.  */
       return uw_frame_state_for (context, fs);
     }
   /* Check if the return address points to a relocation stub.  */
   else if (!TARGET_64BIT
 	   && *(pc + 0) == 0x0fd11082		/* ldw -8(sp),rp */
 	   && (*(pc + 1) == 0xe840c002		/* bv,n r0(rp) */
 	       || *(pc + 1) == 0xe840d002))	/* bve,n (rp) */
     {
       fs->regs.cfa_how    = CFA_REG_OFFSET;
       fs->regs.cfa_reg    = 30;
       fs->regs.cfa_offset = 0;

       fs->retaddr_column = 0;
       fs->regs.reg[0].how = REG_SAVED_OFFSET;
       fs->regs.reg[0].loc.offset = -8;

       /* Update context to describe the stub frame.  */
       uw_update_context (context, fs);

       /* Set up fs to describe the FDE for the caller of this stub.  */
       return uw_frame_state_for (context, fs);
     }

   /* Check if the return address is an export stub as signal handlers
      may return via an export stub.  */
   if (!TARGET_64BIT
       && (*pc & 0xffe0e002) == 0xe8400000	/* bl x,r2 */
       && *(pc + 1) == 0x08000240		/* nop */
       && *(pc + 2) == 0x4bc23fd1		/* ldw -18(sp),rp */
       && *(pc + 3) == 0x004010a1		/* ldsid (rp),r1 */
       && *(pc + 4) == 0x00011820		/* mtsp r1,sr0 */
       && *(pc + 5) == 0xe0400002)		/* be,n 0(sr0,rp) */
     /* Extract target address from PA 1.x 17-bit branch.  */
     pc += extract_17 (*pc) + 2;
   else if (!TARGET_64BIT
 	   && (*pc & 0xfc00e002) == 0xe800a000	/* b,l x,r2 */
 	   && *(pc + 1) == 0x08000240		/* nop */
 	   && *(pc + 2) == 0x4bc23fd1		/* ldw -18(sp),rp */
 	   && *(pc + 3) == 0xe840d002)		/* bve,n (rp) */
     /* Extract target address from PA 2.0 22-bit branch.  */
     pc += extract_22 (*pc) + 2;

   /* Now check if the return address is one of the signal handler
      returns, _sigreturn or _sigsetreturn.  */
   if ((TARGET_64BIT
        && *(pc + 0)  == 0x53db3f51		/* ldd -58(sp),dp */
        && *(pc + 8)  == 0x34160116		/* ldi 8b,r22 */
        && *(pc + 9)  == 0x08360ac1		/* shladd,l r22,3,r1,r1 */
        && *(pc + 10) == 0x0c2010c1		/* ldd 0(r1),r1 */
        && *(pc + 11) == 0xe4202000)		/* be,l 0(sr4,r1) */
       ||
       (TARGET_64BIT
        && *(pc + 0)  == 0x36dc0000		/* ldo 0(r22),ret0 */
        && *(pc + 6)  == 0x341601c0		/* ldi e0,r22 */
        && *(pc + 7)  == 0x08360ac1		/* shladd,l r22,3,r1,r1 */
        && *(pc + 8)  == 0x0c2010c1		/* ldd 0(r1),r1 */
        && *(pc + 9)  == 0xe4202000)		/* be,l 0(sr4,r1) */
       ||
       (!TARGET_64BIT
        && *(pc + 0)  == 0x379a0000		/* ldo 0(ret0),r26 */
        && *(pc + 1)  == 0x6bd33fc9		/* stw r19,-1c(sp) */
        && *(pc + 2)  == 0x20200801		/* ldil L%-40000000,r1 */
        && *(pc + 3)  == 0xe420e008		/* be,l 4(sr7,r1) */
        && *(pc + 4)  == 0x34160116)		/* ldi 8b,r22 */
       ||
       (!TARGET_64BIT
        && *(pc + 0)  == 0x6bd33fc9		/* stw r19,-1c(sp) */
        && *(pc + 1)  == 0x20200801		/* ldil L%-40000000,r1 */
        && *(pc + 2)  == 0xe420e008		/* be,l 4(sr7,r1) */
        && *(pc + 3)  == 0x341601c0))		/* ldi e0,r22 */
     {
       /* The previous stack pointer is saved at (long *)SP - 1.  The
 	 ucontext structure is offset from the start of the previous
 	 frame by the siglocal_misc structure.  */
       struct siglocalx *sl = (struct siglocalx *)
 	(*((long *) context->cfa - 1));
       mcontext_t *mc = &(sl->sl_uc.uc_mcontext);

       long new_cfa = GetSSReg (mc, ss_sp);

       fs->regs.cfa_how = CFA_REG_OFFSET;
       fs->regs.cfa_reg = 30;
       fs->regs.cfa_offset = new_cfa - (long) context->cfa;

       UPDATE_FS_FOR_GR (fs, 1, 1);
       UPDATE_FS_FOR_GR (fs, 2, 2);
       UPDATE_FS_FOR_GR (fs, 3, 3);
       UPDATE_FS_FOR_GR (fs, 4, 4);
       UPDATE_FS_FOR_GR (fs, 5, 5);
       UPDATE_FS_FOR_GR (fs, 6, 6);
       UPDATE_FS_FOR_GR (fs, 7, 7);
       UPDATE_FS_FOR_GR (fs, 8, 8);
       UPDATE_FS_FOR_GR (fs, 9, 9);
       UPDATE_FS_FOR_GR (fs, 10, 10);
       UPDATE_FS_FOR_GR (fs, 11, 11);
       UPDATE_FS_FOR_GR (fs, 12, 12);
       UPDATE_FS_FOR_GR (fs, 13, 13);
       UPDATE_FS_FOR_GR (fs, 14, 14);
       UPDATE_FS_FOR_GR (fs, 15, 15);
       UPDATE_FS_FOR_GR (fs, 16, 16);
       UPDATE_FS_FOR_GR (fs, 17, 17);
       UPDATE_FS_FOR_GR (fs, 18, 18);
       UPDATE_FS_FOR_GR (fs, 19, 19);
       UPDATE_FS_FOR_GR (fs, 20, 20);
       UPDATE_FS_FOR_GR (fs, 21, 21);
       UPDATE_FS_FOR_GR (fs, 22, 22);
       UPDATE_FS_FOR_GR (fs, 23, 23);
       UPDATE_FS_FOR_GR (fs, 24, 24);
       UPDATE_FS_FOR_GR (fs, 25, 25);
       UPDATE_FS_FOR_GR (fs, 26, 26);
       UPDATE_FS_FOR_GR (fs, 27, 27);
       UPDATE_FS_FOR_GR (fs, 28, 28);
       UPDATE_FS_FOR_GR (fs, 29, 29);
       UPDATE_FS_FOR_GR (fs, 30, 30);
       UPDATE_FS_FOR_GR (fs, 31, 31);

       if (TARGET_64BIT)
 	{
 	  UPDATE_FS_FOR_FR (fs, 4, 32);
 	  UPDATE_FS_FOR_FR (fs, 5, 33);
 	  UPDATE_FS_FOR_FR (fs, 6, 34);
 	  UPDATE_FS_FOR_FR (fs, 7, 35);
 	  UPDATE_FS_FOR_FR (fs, 8, 36);
 	  UPDATE_FS_FOR_FR (fs, 9, 37);
 	  UPDATE_FS_FOR_FR (fs, 10, 38);
 	  UPDATE_FS_FOR_FR (fs, 11, 39);
 	  UPDATE_FS_FOR_FR (fs, 12, 40);
 	  UPDATE_FS_FOR_FR (fs, 13, 41);
 	  UPDATE_FS_FOR_FR (fs, 14, 42);
 	  UPDATE_FS_FOR_FR (fs, 15, 43);
 	  UPDATE_FS_FOR_FR (fs, 16, 44);
 	  UPDATE_FS_FOR_FR (fs, 17, 45);
 	  UPDATE_FS_FOR_FR (fs, 18, 46);
 	  UPDATE_FS_FOR_FR (fs, 19, 47);
 	  UPDATE_FS_FOR_FR (fs, 20, 48);
 	  UPDATE_FS_FOR_FR (fs, 21, 49);
 	  UPDATE_FS_FOR_FR (fs, 22, 50);
 	  UPDATE_FS_FOR_FR (fs, 23, 51);
 	  UPDATE_FS_FOR_FR (fs, 24, 52);
 	  UPDATE_FS_FOR_FR (fs, 25, 53);
 	  UPDATE_FS_FOR_FR (fs, 26, 54);
 	  UPDATE_FS_FOR_FR (fs, 27, 55);
 	  UPDATE_FS_FOR_FR (fs, 28, 56);
 	  UPDATE_FS_FOR_FR (fs, 29, 57);
 	  UPDATE_FS_FOR_FR (fs, 30, 58);
 	  UPDATE_FS_FOR_FR (fs, 31, 59);

 	  UPDATE_FS_FOR_SAR (fs, 60);
 	}
       else
 	{
 	  UPDATE_FS_FOR_FR (fs, 4, 32);
 	  UPDATE_FS_FOR_FR (fs, 5, 34);
 	  UPDATE_FS_FOR_FR (fs, 6, 36);
 	  UPDATE_FS_FOR_FR (fs, 7, 38);
 	  UPDATE_FS_FOR_FR (fs, 8, 40);
 	  UPDATE_FS_FOR_FR (fs, 9, 44);
 	  UPDATE_FS_FOR_FR (fs, 10, 44);
 	  UPDATE_FS_FOR_FR (fs, 11, 46);
 	  UPDATE_FS_FOR_FR (fs, 12, 48);
 	  UPDATE_FS_FOR_FR (fs, 13, 50);
 	  UPDATE_FS_FOR_FR (fs, 14, 52);
 	  UPDATE_FS_FOR_FR (fs, 15, 54);

 	  if (!cpu)
 	    cpu = sysconf (_SC_CPU_VERSION);

 	  /* PA-RISC 1.0 only has 16 floating point registers.  */
 	  if (cpu != CPU_PA_RISC1_0)
 	    {
 	      UPDATE_FS_FOR_FR (fs, 16, 56);
 	      UPDATE_FS_FOR_FR (fs, 17, 58);
 	      UPDATE_FS_FOR_FR (fs, 18, 60);
 	      UPDATE_FS_FOR_FR (fs, 19, 62);
 	      UPDATE_FS_FOR_FR (fs, 20, 64);
 	      UPDATE_FS_FOR_FR (fs, 21, 66);
 	      UPDATE_FS_FOR_FR (fs, 22, 68);
 	      UPDATE_FS_FOR_FR (fs, 23, 70);
 	      UPDATE_FS_FOR_FR (fs, 24, 72);
 	      UPDATE_FS_FOR_FR (fs, 25, 74);
 	      UPDATE_FS_FOR_FR (fs, 26, 76);
 	      UPDATE_FS_FOR_FR (fs, 27, 78);
 	      UPDATE_FS_FOR_FR (fs, 28, 80);
 	      UPDATE_FS_FOR_FR (fs, 29, 82);
 	      UPDATE_FS_FOR_FR (fs, 30, 84);
 	      UPDATE_FS_FOR_FR (fs, 31, 86);
 	    }

 	  UPDATE_FS_FOR_SAR (fs, 88);
 	}

       fs->retaddr_column = __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__;
       UPDATE_FS_FOR_PC (fs, __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__);
       fs->signal_frame = 1;

       return _URC_NO_REASON;
     }

   return _URC_END_OF_STACK;
 }
 #endif /* inhibit_libc */
	/* DWARF2 EH unwinding support for PA HP-UX.
	Copyright (C) 2005-2021 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 3, or (at your option)
	any later version.

	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.

	Under Section 7 of GPL version 3, you are granted additional
	permissions described in the GCC Runtime Library Exception, version
	3.1, as published by the Free Software Foundation.

	You should have received a copy of the GNU General Public License and
	a copy of the GCC Runtime Library Exception along with this program;
	see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
	<http://www.gnu.org/licenses/>. */

	/* Do code reading to identify a signal frame, and set the frame
	state data appropriately. See unwind-dw2.c for the structs. */

	/* Don't use this if inhibit_libc is set.
	The build for this target will fail trying to include missing headers. */
	#ifndef inhibit_libc
	#include <signal.h>
	#include <sys/ucontext.h>
	#include <unistd.h>

	/* FIXME: We currently ignore the high halves of general, space and
	control registers on PA 2.0 machines for applications using the
	32-bit runtime. We don't restore space registers or the floating
	point status registers. */

	#define MD_FALLBACK_FRAME_STATE_FOR pa_fallback_frame_state

	/* HP-UX 10.X doesn't define GetSSReg. */
	#ifndef GetSSReg
	#define GetSSReg(ssp, ss_reg) \
	((UseWideRegs (ssp)) \
	? (ssp)->ss_wide.ss_32.ss_reg ## _lo \
	: (ssp)->ss_narrow.ss_reg)
	#endif

	#if TARGET_64BIT
	#define GetSSRegAddr(ssp, ss_reg) ((long) &((ssp)->ss_wide.ss_64.ss_reg))
	#else
	#define GetSSRegAddr(ssp, ss_reg) \
	((UseWideRegs (ssp)) \
	? (long) &((ssp)->ss_wide.ss_32.ss_reg ## _lo) \
	: (long) &((ssp)->ss_narrow.ss_reg))
	#endif

	#define UPDATE_FS_FOR_SAR(FS, N) \
	(FS)->regs.reg[N].how = REG_SAVED_OFFSET; \
	(FS)->regs.reg[N].loc.offset = GetSSRegAddr (mc, ss_cr11) - new_cfa

	#define UPDATE_FS_FOR_GR(FS, GRN, N) \
	(FS)->regs.reg[N].how = REG_SAVED_OFFSET; \
	(FS)->regs.reg[N].loc.offset = GetSSRegAddr (mc, ss_gr##GRN) - new_cfa

	#define UPDATE_FS_FOR_FR(FS, FRN, N) \
	(FS)->regs.reg[N].how = REG_SAVED_OFFSET; \
	(FS)->regs.reg[N].loc.offset = (long) &(mc->ss_fr##FRN) - new_cfa;

	#define UPDATE_FS_FOR_PC(FS, N) \
	(FS)->regs.reg[N].how = REG_SAVED_OFFSET; \
	(FS)->regs.reg[N].loc.offset = GetSSRegAddr (mc, ss_pcoq_head) - new_cfa

	/* Extract bit field from word using HP's numbering (MSB = 0). */
	#define GET_FIELD(X, FROM, TO) \
	((X) >> (31 - (TO)) & ((1 << ((TO) - (FROM) + 1)) - 1))

	static inline int
	sign_extend (int x, int len)
	{
	int signbit = (1 << (len - 1));
	int mask = (signbit << 1) - 1;
	return ((x & mask) ^ signbit) - signbit;
	}

	/* Extract a 17-bit signed constant from branch instructions. */
	static inline int
	extract_17 (unsigned word)
	{
	return sign_extend (GET_FIELD (word, 19, 28)
	\| GET_FIELD (word, 29, 29) << 10
	\| GET_FIELD (word, 11, 15) << 11
	\| (word & 0x1) << 16, 17);
	}

	/* Extract a 22-bit signed constant from branch instructions. */
	static inline int
	extract_22 (unsigned word)
	{
	return sign_extend (GET_FIELD (word, 19, 28)
	\| GET_FIELD (word, 29, 29) << 10
	\| GET_FIELD (word, 11, 15) << 11
	\| GET_FIELD (word, 6, 10) << 16
	\| (word & 0x1) << 21, 22);
	}

	static _Unwind_Reason_Code
	pa_fallback_frame_state (struct _Unwind_Context *context,
	_Unwind_FrameState *fs)
	{
	static long cpu;
	unsigned int pc = (unsigned int ) context->ra;

	if (pc == 0)
	return _URC_END_OF_STACK;

	/* Check for relocation of the return value. */
	if (!TARGET_64BIT
	&& (pc + 0) == 0x2fd01224 / fstd,ma fr4,8(sp) */
	&& (pc + 1) == 0x0fd9109d / ldw -4(sp),ret1 */
	&& (pc + 2) == 0x0fd130bc) / ldw,mb -8(sp),ret0 */
	pc += 3;
	else if (!TARGET_64BIT
	&& (pc + 0) == 0x27d01224 / fstw,ma fr4,8(sp) */
	&& (pc + 1) == 0x0fd130bc) / ldw,mb -8(sp),ret0 */
	pc += 2;
	else if (!TARGET_64BIT
	&& (pc + 0) == 0x0fdc12b0 / stw,ma ret0,8(sp) */
	&& (pc + 1) == 0x0fdd1299 / stw ret1,-4(sp) */
	&& (pc + 2) == 0x2fd13024) / fldd,mb -8(sp),fr4 */
	pc += 3;
	else if (!TARGET_64BIT
	&& (pc + 0) == 0x0fdc12b0 / stw,ma ret0,8(sp) */
	&& (pc + 1) == 0x27d13024) / fldw,mb -8(sp),fr4 */
	pc += 2;

	/* Check if the return address points to an export stub (PA 1.1 or 2.0). */
	if ((!TARGET_64BIT
	&& (pc + 0) == 0x4bc23fd1 / ldw -18(sp),rp */
	&& (pc + 1) == 0x004010a1 / ldsid (rp),r1 */
	&& (pc + 2) == 0x00011820 / mtsp r1,sr0 */
	&& (pc + 3) == 0xe0400002) / be,n 0(sr0,rp) */
	\|\|
	(!TARGET_64BIT
	&& (pc + 0) == 0x4bc23fd1 / ldw -18(sp),rp */
	&& (pc + 1) == 0xe840d002)) / bve,n (rp) */
	{
	fs->regs.cfa_how = CFA_REG_OFFSET;
	fs->regs.cfa_reg = 30;
	fs->regs.cfa_offset = 0;

	fs->retaddr_column = 0;
	fs->regs.reg[0].how = REG_SAVED_OFFSET;
	fs->regs.reg[0].loc.offset = -24;

	/* Update context to describe the stub frame. */
	uw_update_context (context, fs);

	/* Set up fs to describe the FDE for the caller of this stub. */
	return uw_frame_state_for (context, fs);
	}
	/* Check if the return address points to a relocation stub. */
	else if (!TARGET_64BIT
	&& (pc + 0) == 0x0fd11082 / ldw -8(sp),rp */
	&& ((pc + 1) == 0xe840c002 / bv,n r0(rp) */
	\|\| (pc + 1) == 0xe840d002)) / bve,n (rp) */
	{
	fs->regs.cfa_how = CFA_REG_OFFSET;
	fs->regs.cfa_reg = 30;
	fs->regs.cfa_offset = 0;

	fs->retaddr_column = 0;
	fs->regs.reg[0].how = REG_SAVED_OFFSET;
	fs->regs.reg[0].loc.offset = -8;

	/* Update context to describe the stub frame. */
	uw_update_context (context, fs);

	/* Set up fs to describe the FDE for the caller of this stub. */
	return uw_frame_state_for (context, fs);
	}

	/* Check if the return address is an export stub as signal handlers
	may return via an export stub. */
	if (!TARGET_64BIT
	&& (pc & 0xffe0e002) == 0xe8400000 / bl x,r2 */
	&& (pc + 1) == 0x08000240 / nop */
	&& (pc + 2) == 0x4bc23fd1 / ldw -18(sp),rp */
	&& (pc + 3) == 0x004010a1 / ldsid (rp),r1 */
	&& (pc + 4) == 0x00011820 / mtsp r1,sr0 */
	&& (pc + 5) == 0xe0400002) / be,n 0(sr0,rp) */
	/* Extract target address from PA 1.x 17-bit branch. */
	pc += extract_17 (*pc) + 2;
	else if (!TARGET_64BIT
	&& (pc & 0xfc00e002) == 0xe800a000 / b,l x,r2 */
	&& (pc + 1) == 0x08000240 / nop */
	&& (pc + 2) == 0x4bc23fd1 / ldw -18(sp),rp */
	&& (pc + 3) == 0xe840d002) / bve,n (rp) */
	/* Extract target address from PA 2.0 22-bit branch. */
	pc += extract_22 (*pc) + 2;

	/* Now check if the return address is one of the signal handler
	returns, _sigreturn or _sigsetreturn. */
	if ((TARGET_64BIT
	&& (pc + 0) == 0x53db3f51 / ldd -58(sp),dp */
	&& (pc + 8) == 0x34160116 / ldi 8b,r22 */
	&& (pc + 9) == 0x08360ac1 / shladd,l r22,3,r1,r1 */
	&& (pc + 10) == 0x0c2010c1 / ldd 0(r1),r1 */
	&& (pc + 11) == 0xe4202000) / be,l 0(sr4,r1) */
	\|\|
	(TARGET_64BIT
	&& (pc + 0) == 0x36dc0000 / ldo 0(r22),ret0 */
	&& (pc + 6) == 0x341601c0 / ldi e0,r22 */
	&& (pc + 7) == 0x08360ac1 / shladd,l r22,3,r1,r1 */
	&& (pc + 8) == 0x0c2010c1 / ldd 0(r1),r1 */
	&& (pc + 9) == 0xe4202000) / be,l 0(sr4,r1) */
	\|\|
	(!TARGET_64BIT
	&& (pc + 0) == 0x379a0000 / ldo 0(ret0),r26 */
	&& (pc + 1) == 0x6bd33fc9 / stw r19,-1c(sp) */
	&& (pc + 2) == 0x20200801 / ldil L%-40000000,r1 */
	&& (pc + 3) == 0xe420e008 / be,l 4(sr7,r1) */
	&& (pc + 4) == 0x34160116) / ldi 8b,r22 */
	\|\|
	(!TARGET_64BIT
	&& (pc + 0) == 0x6bd33fc9 / stw r19,-1c(sp) */
	&& (pc + 1) == 0x20200801 / ldil L%-40000000,r1 */
	&& (pc + 2) == 0xe420e008 / be,l 4(sr7,r1) */
	&& (pc + 3) == 0x341601c0)) / ldi e0,r22 */
	{
	/* The previous stack pointer is saved at (long *)SP - 1. The
	ucontext structure is offset from the start of the previous
	frame by the siglocal_misc structure. */
	struct siglocalx sl = (struct siglocalx )
	(((long ) context->cfa - 1));
	mcontext_t *mc = &(sl->sl_uc.uc_mcontext);

	long new_cfa = GetSSReg (mc, ss_sp);

	fs->regs.cfa_how = CFA_REG_OFFSET;
	fs->regs.cfa_reg = 30;
	fs->regs.cfa_offset = new_cfa - (long) context->cfa;

	UPDATE_FS_FOR_GR (fs, 1, 1);
	UPDATE_FS_FOR_GR (fs, 2, 2);
	UPDATE_FS_FOR_GR (fs, 3, 3);
	UPDATE_FS_FOR_GR (fs, 4, 4);
	UPDATE_FS_FOR_GR (fs, 5, 5);
	UPDATE_FS_FOR_GR (fs, 6, 6);
	UPDATE_FS_FOR_GR (fs, 7, 7);
	UPDATE_FS_FOR_GR (fs, 8, 8);
	UPDATE_FS_FOR_GR (fs, 9, 9);
	UPDATE_FS_FOR_GR (fs, 10, 10);
	UPDATE_FS_FOR_GR (fs, 11, 11);
	UPDATE_FS_FOR_GR (fs, 12, 12);
	UPDATE_FS_FOR_GR (fs, 13, 13);
	UPDATE_FS_FOR_GR (fs, 14, 14);
	UPDATE_FS_FOR_GR (fs, 15, 15);
	UPDATE_FS_FOR_GR (fs, 16, 16);
	UPDATE_FS_FOR_GR (fs, 17, 17);
	UPDATE_FS_FOR_GR (fs, 18, 18);
	UPDATE_FS_FOR_GR (fs, 19, 19);
	UPDATE_FS_FOR_GR (fs, 20, 20);
	UPDATE_FS_FOR_GR (fs, 21, 21);
	UPDATE_FS_FOR_GR (fs, 22, 22);
	UPDATE_FS_FOR_GR (fs, 23, 23);
	UPDATE_FS_FOR_GR (fs, 24, 24);
	UPDATE_FS_FOR_GR (fs, 25, 25);
	UPDATE_FS_FOR_GR (fs, 26, 26);
	UPDATE_FS_FOR_GR (fs, 27, 27);
	UPDATE_FS_FOR_GR (fs, 28, 28);
	UPDATE_FS_FOR_GR (fs, 29, 29);
	UPDATE_FS_FOR_GR (fs, 30, 30);
	UPDATE_FS_FOR_GR (fs, 31, 31);

	if (TARGET_64BIT)
	{
	UPDATE_FS_FOR_FR (fs, 4, 32);
	UPDATE_FS_FOR_FR (fs, 5, 33);
	UPDATE_FS_FOR_FR (fs, 6, 34);
	UPDATE_FS_FOR_FR (fs, 7, 35);
	UPDATE_FS_FOR_FR (fs, 8, 36);
	UPDATE_FS_FOR_FR (fs, 9, 37);
	UPDATE_FS_FOR_FR (fs, 10, 38);
	UPDATE_FS_FOR_FR (fs, 11, 39);
	UPDATE_FS_FOR_FR (fs, 12, 40);
	UPDATE_FS_FOR_FR (fs, 13, 41);
	UPDATE_FS_FOR_FR (fs, 14, 42);
	UPDATE_FS_FOR_FR (fs, 15, 43);
	UPDATE_FS_FOR_FR (fs, 16, 44);
	UPDATE_FS_FOR_FR (fs, 17, 45);
	UPDATE_FS_FOR_FR (fs, 18, 46);
	UPDATE_FS_FOR_FR (fs, 19, 47);
	UPDATE_FS_FOR_FR (fs, 20, 48);
	UPDATE_FS_FOR_FR (fs, 21, 49);
	UPDATE_FS_FOR_FR (fs, 22, 50);
	UPDATE_FS_FOR_FR (fs, 23, 51);
	UPDATE_FS_FOR_FR (fs, 24, 52);
	UPDATE_FS_FOR_FR (fs, 25, 53);
	UPDATE_FS_FOR_FR (fs, 26, 54);
	UPDATE_FS_FOR_FR (fs, 27, 55);
	UPDATE_FS_FOR_FR (fs, 28, 56);
	UPDATE_FS_FOR_FR (fs, 29, 57);
	UPDATE_FS_FOR_FR (fs, 30, 58);
	UPDATE_FS_FOR_FR (fs, 31, 59);

	UPDATE_FS_FOR_SAR (fs, 60);
	}
	else
	{
	UPDATE_FS_FOR_FR (fs, 4, 32);
	UPDATE_FS_FOR_FR (fs, 5, 34);
	UPDATE_FS_FOR_FR (fs, 6, 36);
	UPDATE_FS_FOR_FR (fs, 7, 38);
	UPDATE_FS_FOR_FR (fs, 8, 40);
	UPDATE_FS_FOR_FR (fs, 9, 44);
	UPDATE_FS_FOR_FR (fs, 10, 44);
	UPDATE_FS_FOR_FR (fs, 11, 46);
	UPDATE_FS_FOR_FR (fs, 12, 48);
	UPDATE_FS_FOR_FR (fs, 13, 50);
	UPDATE_FS_FOR_FR (fs, 14, 52);
	UPDATE_FS_FOR_FR (fs, 15, 54);

	if (!cpu)
	cpu = sysconf (_SC_CPU_VERSION);

	/* PA-RISC 1.0 only has 16 floating point registers. */
	if (cpu != CPU_PA_RISC1_0)
	{
	UPDATE_FS_FOR_FR (fs, 16, 56);
	UPDATE_FS_FOR_FR (fs, 17, 58);
	UPDATE_FS_FOR_FR (fs, 18, 60);
	UPDATE_FS_FOR_FR (fs, 19, 62);
	UPDATE_FS_FOR_FR (fs, 20, 64);
	UPDATE_FS_FOR_FR (fs, 21, 66);
	UPDATE_FS_FOR_FR (fs, 22, 68);
	UPDATE_FS_FOR_FR (fs, 23, 70);
	UPDATE_FS_FOR_FR (fs, 24, 72);
	UPDATE_FS_FOR_FR (fs, 25, 74);
	UPDATE_FS_FOR_FR (fs, 26, 76);
	UPDATE_FS_FOR_FR (fs, 27, 78);
	UPDATE_FS_FOR_FR (fs, 28, 80);
	UPDATE_FS_FOR_FR (fs, 29, 82);
	UPDATE_FS_FOR_FR (fs, 30, 84);
	UPDATE_FS_FOR_FR (fs, 31, 86);
	}

	UPDATE_FS_FOR_SAR (fs, 88);
	}

	fs->retaddr_column = __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__;
	UPDATE_FS_FOR_PC (fs, __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__);
	fs->signal_frame = 1;

	return _URC_NO_REASON;
	}

	return _URC_END_OF_STACK;
	}
	#endif /* inhibit_libc */