===================================================================
@@ -354,20 +354,22 @@ frob_update_context (struct _Unwind_Cont
/* We are in a plt call stub or r2 adjusting long branch stub,
before r2 has been saved. Keep REG_UNSAVED. */
}
- else if (pc[0] == 0x4E800421
- && pc[1] == 0xE8410028)
- {
- /* We are at the bctrl instruction in a call via function
- pointer. gcc always emits the load of the new r2 just
- before the bctrl. */
- _Unwind_SetGRPtr (context, 2, context->cfa + 40);
- }
else
{
unsigned int *insn
= (unsigned int *) _Unwind_GetGR (context, R_LR);
if (insn && *insn == 0xE8410028)
_Unwind_SetGRPtr (context, 2, context->cfa + 40);
+ else if (pc[0] == 0x4E800421
+ && pc[1] == 0xE8410028)
+ {
+ /* We are at the bctrl instruction in a call via function
+ pointer. gcc always emits the load of the new R2 just
+ before the bctrl so this is the first and only place
+ we need to use the stored R2. */
+ _Unwind_Word sp = _Unwind_GetGR (context, 1);
+ _Unwind_SetGRPtr (context, 2, sp + 40);
+ }
}
}
#endif
===================================================================
@@ -172,8 +172,6 @@ extern void rs6000_emit_epilogue (int);
extern void rs6000_emit_eh_reg_restore (rtx, rtx);
extern const char * output_isel (rtx *);
extern void rs6000_call_indirect_aix (rtx, rtx, rtx);
-extern bool rs6000_save_toc_in_prologue_p (void);
-
extern void rs6000_aix_asm_output_dwarf_table_ref (char *);
/* Declare functions in rs6000-c.c */
===================================================================
@@ -1178,6 +1178,7 @@ static void rs6000_conditional_register_
static void rs6000_trampoline_init (rtx, tree, rtx);
static bool rs6000_cannot_force_const_mem (enum machine_mode, rtx);
static bool rs6000_legitimate_constant_p (enum machine_mode, rtx);
+static bool rs6000_save_toc_in_prologue_p (void);
/* Hash table stuff for keeping track of TOC entries. */
@@ -20478,14 +20504,12 @@ rs6000_emit_prologue (void)
insn = emit_insn (generate_set_vrsave (reg, info, 0));
}
- if (TARGET_SINGLE_PIC_BASE)
- return; /* Do not set PIC register */
-
/* If we are using RS6000_PIC_OFFSET_TABLE_REGNUM, we need to set it up. */
- if ((TARGET_TOC && TARGET_MINIMAL_TOC && get_pool_size () != 0)
- || (DEFAULT_ABI == ABI_V4
- && (flag_pic == 1 || (flag_pic && TARGET_SECURE_PLT))
- && df_regs_ever_live_p (RS6000_PIC_OFFSET_TABLE_REGNUM)))
+ if (!TARGET_SINGLE_PIC_BASE
+ && ((TARGET_TOC && TARGET_MINIMAL_TOC && get_pool_size () != 0)
+ || (DEFAULT_ABI == ABI_V4
+ && (flag_pic == 1 || (flag_pic && TARGET_SECURE_PLT))
+ && df_regs_ever_live_p (RS6000_PIC_OFFSET_TABLE_REGNUM))))
{
/* If emit_load_toc_table will use the link register, we need to save
it. We use R12 for this purpose because emit_load_toc_table
@@ -20513,7 +20537,8 @@ rs6000_emit_prologue (void)
}
#if TARGET_MACHO
- if (DEFAULT_ABI == ABI_DARWIN
+ if (!TARGET_SINGLE_PIC_BASE
+ && DEFAULT_ABI == ABI_DARWIN
&& flag_pic && crtl->uses_pic_offset_table)
{
rtx lr = gen_rtx_REG (Pmode, LR_REGNO);
@@ -20534,10 +20559,26 @@ rs6000_emit_prologue (void)
}
#endif
- /* If we need to, save the TOC register after doing the stack setup. */
+ /* If we need to, save the TOC register after doing the stack setup.
+ Do not emit eh frame info for this save. We don't attempt to
+ write accurate DWARF EH frame info for R2 because code emitted by
+ gcc for a (non-pointer) function call doesn't save and restore
+ R2. Instead, R2 is managed out-of-line by a linker generated plt
+ call stub when the function resides in a shared library. This
+ behaviour is costly to describe in DWARF, both in terms of the
+ size of DWARF info and the time taken in the unwinder to
+ interpret it. R2 changes, apart from the calls_eh_return case
+ earlier in this function, are handled by linux-unwind.h
+ frob_update_context. Even in frob_update_context we don't try to
+ keep the unwinder's copy of R2 accurate on an instruction by
+ instruction basis, as we only need it set to the correct TOC
+ pointer for the current frame. */
if (rs6000_save_toc_in_prologue_p ())
- emit_frame_save (sp_reg_rtx, sp_reg_rtx, reg_mode, TOC_REGNUM,
- 5 * reg_size, info->total_size);
+ {
+ rtx addr = gen_rtx_PLUS (Pmode, sp_reg_rtx, GEN_INT (5 * reg_size));
+ rtx mem = gen_frame_mem (reg_mode, addr);
+ emit_move_insn (mem, gen_rtx_REG (reg_mode, TOC_REGNUM));
+ }
}
/* Write function prologue. */
@@ -27795,10 +27838,7 @@ rs6000_call_indirect_aix (rtx value, rtx
/* Can we optimize saving the TOC in the prologue or do we need to do it at
every call? */
- if (TARGET_SAVE_TOC_INDIRECT && !cfun->calls_alloca
- && !cfun->calls_setjmp && !cfun->has_nonlocal_label
- && !cfun->can_throw_non_call_exceptions
- && ((flags_from_decl_or_type (cfun->decl) & ECF_NOTHROW) == ECF_NOTHROW))
+ if (TARGET_SAVE_TOC_INDIRECT && !cfun->calls_alloca)
cfun->machine->save_toc_in_prologue = true;
else
@@ -27834,13 +27874,12 @@ rs6000_call_indirect_aix (rtx value, rtx
insn = call_func (func_addr, flag, func_toc_mem, stack_toc_mem);
emit_call_insn (insn);
- return;
}
/* Return whether we need to always update the saved TOC pointer when we update
the stack pointer. */
-bool
+static bool
rs6000_save_toc_in_prologue_p (void)
{
return (cfun && cfun->machine && cfun->machine->save_toc_in_prologue);