re PR java/6748 (Array_3 testcase failing on powerpc-linux-gnu)

2003-01-23  Franz Sirl  <Franz.Sirl-kernel@lauterbach.com>

	PR java/6748
	* config/rs6000/linux.h (MD_FALLBACK_FRAME_STATE_FOR): Don't destroy
	regs->nip. Fix rt_sigreturn frame layout. Add support for newer
	kernels.

From-SVN: r61675

gcc/ChangeLog

+2003-01-23  Franz Sirl  <Franz.Sirl-kernel@lauterbach.com>
+
+	PR java/6748
+	* config/rs6000/linux.h (MD_FALLBACK_FRAME_STATE_FOR): Don't destroy
+	regs->nip. Fix rt_sigreturn frame layout. Add support for newer
+	kernels.
+
 2003-01-23  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
 
 	* cpplex.c (cpp_interpret_charconst): Squelch warning with cast.

gcc/config/rs6000/linux.h

 /* Definitions of target machine for GNU compiler,
    for PowerPC machines running Linux.
-   Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, 
-   Inc.
+   Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
+   Free Software Foundation, Inc.
    Contributed by Michael Meissner (meissner@cygnus.com).
 
 This file is part of GNU CC.
@@ -96,12 +96,34 @@ enum { SIGNAL_FRAMESIZE = 64 };
     long new_cfa_;							\
     int i_;								\
 									\
-    /* li r0, 0x7777; sc  (rt_sigreturn)  */				\
-    /* li r0, 0x6666; sc  (sigreturn)  */				\
-    if (((*(unsigned int *) (pc_+0) == 0x38007777)			\
-	 || (*(unsigned int *) (pc_+0) == 0x38006666))			\
-	&& (*(unsigned int *) (pc_+4)  == 0x44000002))			\
-	sc_ = (CONTEXT)->cfa + SIGNAL_FRAMESIZE;			\
+    /* 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)			\
+      break;								\
+    if (*(unsigned int *) (pc_+0) == 0x38007777				\
+	|| *(unsigned int *) (pc_+0) == 0x38000077)			\
+      {									\
+	struct sigframe {						\
+	  char gap[SIGNAL_FRAMESIZE];					\
+	  struct sigcontext sigctx;					\
+	} *rt_ = (CONTEXT)->cfa;					\
+	sc_ = &rt_->sigctx;						\
+      }									\
+    else if (*(unsigned int *) (pc_+0) == 0x38006666			\
+	     || *(unsigned int *) (pc_+0) == 0x380000AC)		\
+      {									\
+	struct rt_sigframe {						\
+	  char gap[SIGNAL_FRAMESIZE];					\
+	  unsigned long _unused[2];					\
+	  struct siginfo *pinfo;					\
+	  void *puc;							\
+	  struct siginfo info;						\
+	  struct ucontext uc;						\
+	} *rt_ = (CONTEXT)->cfa;					\
+	sc_ = &rt_->uc.uc_mcontext;					\
+      }									\
     else								\
       break;								\
     									\
@@ -124,11 +146,13 @@ enum { SIGNAL_FRAMESIZE = 64 };
 									\
     /* The unwinder expects the IP to point to the following insn,	\
        whereas the kernel returns the address of the actual		\
-       faulting insn.  */						\
-    sc_->regs->nip += 4;  						\
+       faulting insn. We store NIP+4 in an unused register slot to	\
+       get the same result for multiple evaluation of the same signal	\
+       frame.  */							\
+    sc_->regs->gpr[47] = sc_->regs->nip + 4;  				\
     (FS)->regs.reg[CR0_REGNO].how = REG_SAVED_OFFSET;			\
     (FS)->regs.reg[CR0_REGNO].loc.offset 				\
-      = (long)&(sc_->regs->nip) - new_cfa_;				\
+      = (long)&(sc_->regs->gpr[47]) - new_cfa_;				\
     (FS)->retaddr_column = CR0_REGNO;					\
     goto SUCCESS;							\
   } while (0)