From: Richard Sandiford Date: Wed, 20 Dec 2017 12:54:44 +0000 (+0000) Subject: poly_int: DWARF CFA offsets X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=21810de45dcfec0ac4141dfa6a59e0f0859aed3e;p=gcc.git poly_int: DWARF CFA offsets This patch makes the DWARF code use poly_int64 rather than HOST_WIDE_INT for CFA offsets. The main changes are: - to make reg_save use a DW_CFA_expression representation when the offset isn't constant and - to record the CFA information alongside a def_cfa_expression if either offset is polynomial, since it's quite difficult to reconstruct the CFA information otherwise. 2017-12-20 Richard Sandiford Alan Hayward David Sherwood gcc/ * gengtype.c (main): Handle poly_int64_pod. * dwarf2out.h (dw_cfi_oprnd_cfa_loc): New dw_cfi_oprnd_type. (dw_cfi_oprnd::dw_cfi_cfa_loc): New field. (dw_cfa_location::offset, dw_cfa_location::base_offset): Change from HOST_WIDE_INT to poly_int64_pod. * dwarf2cfi.c (queued_reg_save::cfa_offset): Likewise. (copy_cfa): New function. (lookup_cfa_1): Use the cached dw_cfi_cfa_loc, if it exists. (cfi_oprnd_equal_p): Handle dw_cfi_oprnd_cfa_loc. (cfa_equal_p, dwarf2out_frame_debug_adjust_cfa) (dwarf2out_frame_debug_cfa_offset, dwarf2out_frame_debug_expr) (initial_return_save): Treat offsets as poly_ints. (def_cfa_0): Likewise. Cache the CFA in dw_cfi_cfa_loc if either offset is nonconstant. (reg_save): Take the offset as a poly_int64. Fall back to DW_CFA_expression for nonconstant offsets. (queue_reg_save): Take the offset as a poly_int64. * dwarf2out.c (dw_cfi_oprnd2_desc): Handle DW_CFA_def_cfa_expression. Co-Authored-By: Alan Hayward Co-Authored-By: David Sherwood From-SVN: r255884 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index fa0a3ce3dec..7bb3f5d5371 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,26 @@ +2017-12-20 Richard Sandiford + Alan Hayward + David Sherwood + + * gengtype.c (main): Handle poly_int64_pod. + * dwarf2out.h (dw_cfi_oprnd_cfa_loc): New dw_cfi_oprnd_type. + (dw_cfi_oprnd::dw_cfi_cfa_loc): New field. + (dw_cfa_location::offset, dw_cfa_location::base_offset): Change + from HOST_WIDE_INT to poly_int64_pod. + * dwarf2cfi.c (queued_reg_save::cfa_offset): Likewise. + (copy_cfa): New function. + (lookup_cfa_1): Use the cached dw_cfi_cfa_loc, if it exists. + (cfi_oprnd_equal_p): Handle dw_cfi_oprnd_cfa_loc. + (cfa_equal_p, dwarf2out_frame_debug_adjust_cfa) + (dwarf2out_frame_debug_cfa_offset, dwarf2out_frame_debug_expr) + (initial_return_save): Treat offsets as poly_ints. + (def_cfa_0): Likewise. Cache the CFA in dw_cfi_cfa_loc if either + offset is nonconstant. + (reg_save): Take the offset as a poly_int64. Fall back to + DW_CFA_expression for nonconstant offsets. + (queue_reg_save): Take the offset as a poly_int64. + * dwarf2out.c (dw_cfi_oprnd2_desc): Handle DW_CFA_def_cfa_expression. + 2017-12-20 Richard Sandiford Alan Hayward David Sherwood diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c index 62117e7c850..8d08d86df12 100644 --- a/gcc/dwarf2cfi.c +++ b/gcc/dwarf2cfi.c @@ -206,7 +206,7 @@ static dw_cfa_location *cur_cfa; struct queued_reg_save { rtx reg; rtx saved_reg; - HOST_WIDE_INT cfa_offset; + poly_int64_pod cfa_offset; }; @@ -434,6 +434,16 @@ copy_cfi_row (dw_cfi_row *src) return dst; } +/* Return a copy of an existing CFA location. */ + +static dw_cfa_location * +copy_cfa (dw_cfa_location *src) +{ + dw_cfa_location *dst = ggc_alloc (); + *dst = *src; + return dst; +} + /* Generate a new label for the CFI info to refer to. */ static char * @@ -629,7 +639,10 @@ lookup_cfa_1 (dw_cfi_ref cfi, dw_cfa_location *loc, dw_cfa_location *remember) loc->offset = cfi->dw_cfi_oprnd2.dw_cfi_offset; break; case DW_CFA_def_cfa_expression: - get_cfa_from_loc_descr (loc, cfi->dw_cfi_oprnd1.dw_cfi_loc); + if (cfi->dw_cfi_oprnd2.dw_cfi_cfa_loc) + *loc = *cfi->dw_cfi_oprnd2.dw_cfi_cfa_loc; + else + get_cfa_from_loc_descr (loc, cfi->dw_cfi_oprnd1.dw_cfi_loc); break; case DW_CFA_remember_state: @@ -654,10 +667,10 @@ bool cfa_equal_p (const dw_cfa_location *loc1, const dw_cfa_location *loc2) { return (loc1->reg == loc2->reg - && loc1->offset == loc2->offset + && known_eq (loc1->offset, loc2->offset) && loc1->indirect == loc2->indirect && (loc1->indirect == 0 - || loc1->base_offset == loc2->base_offset)); + || known_eq (loc1->base_offset, loc2->base_offset))); } /* Determine if two CFI operands are identical. */ @@ -678,6 +691,8 @@ cfi_oprnd_equal_p (enum dw_cfi_oprnd_type t, dw_cfi_oprnd *a, dw_cfi_oprnd *b) || strcmp (a->dw_cfi_addr, b->dw_cfi_addr) == 0); case dw_cfi_oprnd_loc: return loc_descr_equal_p (a->dw_cfi_loc, b->dw_cfi_loc); + case dw_cfi_oprnd_cfa_loc: + return cfa_equal_p (a->dw_cfi_cfa_loc, b->dw_cfi_cfa_loc); } gcc_unreachable (); } @@ -758,42 +773,50 @@ def_cfa_0 (dw_cfa_location *old_cfa, dw_cfa_location *new_cfa) cfi = new_cfi (); - if (new_cfa->reg == old_cfa->reg && !new_cfa->indirect && !old_cfa->indirect) + HOST_WIDE_INT const_offset; + if (new_cfa->reg == old_cfa->reg + && !new_cfa->indirect + && !old_cfa->indirect + && new_cfa->offset.is_constant (&const_offset)) { /* Construct a "DW_CFA_def_cfa_offset " instruction, indicating the CFA register did not change but the offset did. The data factoring for DW_CFA_def_cfa_offset_sf happens in output_cfi, or in the assembler via the .cfi_def_cfa_offset directive. */ - if (new_cfa->offset < 0) + if (const_offset < 0) cfi->dw_cfi_opc = DW_CFA_def_cfa_offset_sf; else cfi->dw_cfi_opc = DW_CFA_def_cfa_offset; - cfi->dw_cfi_oprnd1.dw_cfi_offset = new_cfa->offset; + cfi->dw_cfi_oprnd1.dw_cfi_offset = const_offset; } - else if (new_cfa->offset == old_cfa->offset + else if (new_cfa->offset.is_constant () + && known_eq (new_cfa->offset, old_cfa->offset) && old_cfa->reg != INVALID_REGNUM && !new_cfa->indirect && !old_cfa->indirect) { /* Construct a "DW_CFA_def_cfa_register " instruction, indicating the CFA register has changed to but the - offset has not changed. */ + offset has not changed. This requires the old CFA to have + been set as a register plus offset rather than a general + DW_CFA_def_cfa_expression. */ cfi->dw_cfi_opc = DW_CFA_def_cfa_register; cfi->dw_cfi_oprnd1.dw_cfi_reg_num = new_cfa->reg; } - else if (new_cfa->indirect == 0) + else if (new_cfa->indirect == 0 + && new_cfa->offset.is_constant (&const_offset)) { /* Construct a "DW_CFA_def_cfa " instruction, indicating the CFA register has changed to with the specified offset. The data factoring for DW_CFA_def_cfa_sf happens in output_cfi, or in the assembler via the .cfi_def_cfa directive. */ - if (new_cfa->offset < 0) + if (const_offset < 0) cfi->dw_cfi_opc = DW_CFA_def_cfa_sf; else cfi->dw_cfi_opc = DW_CFA_def_cfa; cfi->dw_cfi_oprnd1.dw_cfi_reg_num = new_cfa->reg; - cfi->dw_cfi_oprnd2.dw_cfi_offset = new_cfa->offset; + cfi->dw_cfi_oprnd2.dw_cfi_offset = const_offset; } else { @@ -805,6 +828,13 @@ def_cfa_0 (dw_cfa_location *old_cfa, dw_cfa_location *new_cfa) cfi->dw_cfi_opc = DW_CFA_def_cfa_expression; loc_list = build_cfa_loc (new_cfa, 0); cfi->dw_cfi_oprnd1.dw_cfi_loc = loc_list; + if (!new_cfa->offset.is_constant () + || !new_cfa->base_offset.is_constant ()) + /* It's hard to reconstruct the CFA location for a polynomial + expression, so just cache it instead. */ + cfi->dw_cfi_oprnd2.dw_cfi_cfa_loc = copy_cfa (new_cfa); + else + cfi->dw_cfi_oprnd2.dw_cfi_cfa_loc = NULL; } return cfi; @@ -836,33 +866,42 @@ def_cfa_1 (dw_cfa_location *new_cfa) otherwise it is saved in SREG. */ static void -reg_save (unsigned int reg, unsigned int sreg, HOST_WIDE_INT offset) +reg_save (unsigned int reg, unsigned int sreg, poly_int64 offset) { dw_fde_ref fde = cfun ? cfun->fde : NULL; dw_cfi_ref cfi = new_cfi (); cfi->dw_cfi_oprnd1.dw_cfi_reg_num = reg; - /* When stack is aligned, store REG using DW_CFA_expression with FP. */ - if (fde - && fde->stack_realign - && sreg == INVALID_REGNUM) - { - cfi->dw_cfi_opc = DW_CFA_expression; - cfi->dw_cfi_oprnd1.dw_cfi_reg_num = reg; - cfi->dw_cfi_oprnd2.dw_cfi_loc - = build_cfa_aligned_loc (&cur_row->cfa, offset, - fde->stack_realignment); - } - else if (sreg == INVALID_REGNUM) + if (sreg == INVALID_REGNUM) { - if (need_data_align_sf_opcode (offset)) - cfi->dw_cfi_opc = DW_CFA_offset_extended_sf; - else if (reg & ~0x3f) - cfi->dw_cfi_opc = DW_CFA_offset_extended; + HOST_WIDE_INT const_offset; + /* When stack is aligned, store REG using DW_CFA_expression with FP. */ + if (fde && fde->stack_realign) + { + cfi->dw_cfi_opc = DW_CFA_expression; + cfi->dw_cfi_oprnd1.dw_cfi_reg_num = reg; + cfi->dw_cfi_oprnd2.dw_cfi_loc + = build_cfa_aligned_loc (&cur_row->cfa, offset, + fde->stack_realignment); + } + else if (offset.is_constant (&const_offset)) + { + if (need_data_align_sf_opcode (const_offset)) + cfi->dw_cfi_opc = DW_CFA_offset_extended_sf; + else if (reg & ~0x3f) + cfi->dw_cfi_opc = DW_CFA_offset_extended; + else + cfi->dw_cfi_opc = DW_CFA_offset; + cfi->dw_cfi_oprnd2.dw_cfi_offset = const_offset; + } else - cfi->dw_cfi_opc = DW_CFA_offset; - cfi->dw_cfi_oprnd2.dw_cfi_offset = offset; + { + cfi->dw_cfi_opc = DW_CFA_expression; + cfi->dw_cfi_oprnd1.dw_cfi_reg_num = reg; + cfi->dw_cfi_oprnd2.dw_cfi_loc + = build_cfa_loc (&cur_row->cfa, offset); + } } else if (sreg == reg) { @@ -995,7 +1034,7 @@ record_reg_saved_in_reg (rtx dest, rtx src) SREG, or if SREG is NULL then it is saved at OFFSET to the CFA. */ static void -queue_reg_save (rtx reg, rtx sreg, HOST_WIDE_INT offset) +queue_reg_save (rtx reg, rtx sreg, poly_int64 offset) { queued_reg_save *q; queued_reg_save e = {reg, sreg, offset}; @@ -1097,20 +1136,11 @@ dwarf2out_frame_debug_def_cfa (rtx pat) { memset (cur_cfa, 0, sizeof (*cur_cfa)); - if (GET_CODE (pat) == PLUS) - { - cur_cfa->offset = INTVAL (XEXP (pat, 1)); - pat = XEXP (pat, 0); - } + pat = strip_offset (pat, &cur_cfa->offset); if (MEM_P (pat)) { cur_cfa->indirect = 1; - pat = XEXP (pat, 0); - if (GET_CODE (pat) == PLUS) - { - cur_cfa->base_offset = INTVAL (XEXP (pat, 1)); - pat = XEXP (pat, 0); - } + pat = strip_offset (XEXP (pat, 0), &cur_cfa->base_offset); } /* ??? If this fails, we could be calling into the _loc functions to define a full expression. So far no port does that. */ @@ -1133,7 +1163,7 @@ dwarf2out_frame_debug_adjust_cfa (rtx pat) { case PLUS: gcc_assert (dwf_regno (XEXP (src, 0)) == cur_cfa->reg); - cur_cfa->offset -= INTVAL (XEXP (src, 1)); + cur_cfa->offset -= rtx_to_poly_int64 (XEXP (src, 1)); break; case REG: @@ -1152,7 +1182,7 @@ dwarf2out_frame_debug_adjust_cfa (rtx pat) static void dwarf2out_frame_debug_cfa_offset (rtx set) { - HOST_WIDE_INT offset; + poly_int64 offset; rtx src, addr, span; unsigned int sregno; @@ -1170,7 +1200,7 @@ dwarf2out_frame_debug_cfa_offset (rtx set) break; case PLUS: gcc_assert (dwf_regno (XEXP (addr, 0)) == cur_cfa->reg); - offset = INTVAL (XEXP (addr, 1)) - cur_cfa->offset; + offset = rtx_to_poly_int64 (XEXP (addr, 1)) - cur_cfa->offset; break; default: gcc_unreachable (); @@ -1195,7 +1225,7 @@ dwarf2out_frame_debug_cfa_offset (rtx set) { /* We have a PARALLEL describing where the contents of SRC live. Adjust the offset for each piece of the PARALLEL. */ - HOST_WIDE_INT span_offset = offset; + poly_int64 span_offset = offset; gcc_assert (GET_CODE (span) == PARALLEL); @@ -1535,7 +1565,7 @@ static void dwarf2out_frame_debug_expr (rtx expr) { rtx src, dest, span; - HOST_WIDE_INT offset; + poly_int64 offset; dw_fde_ref fde; /* If RTX_FRAME_RELATED_P is set on a PARALLEL, process each member of @@ -1639,19 +1669,14 @@ dwarf2out_frame_debug_expr (rtx expr) { /* Rule 2 */ /* Adjusting SP. */ - switch (GET_CODE (XEXP (src, 1))) + if (REG_P (XEXP (src, 1))) { - case CONST_INT: - offset = INTVAL (XEXP (src, 1)); - break; - case REG: gcc_assert (dwf_regno (XEXP (src, 1)) == cur_trace->cfa_temp.reg); offset = cur_trace->cfa_temp.offset; - break; - default: - gcc_unreachable (); } + else if (!poly_int_rtx_p (XEXP (src, 1), &offset)) + gcc_unreachable (); if (XEXP (src, 0) == hard_frame_pointer_rtx) { @@ -1680,9 +1705,8 @@ dwarf2out_frame_debug_expr (rtx expr) gcc_assert (frame_pointer_needed); gcc_assert (REG_P (XEXP (src, 0)) - && dwf_regno (XEXP (src, 0)) == cur_cfa->reg - && CONST_INT_P (XEXP (src, 1))); - offset = INTVAL (XEXP (src, 1)); + && dwf_regno (XEXP (src, 0)) == cur_cfa->reg); + offset = rtx_to_poly_int64 (XEXP (src, 1)); if (GET_CODE (src) != MINUS) offset = -offset; cur_cfa->offset += offset; @@ -1695,11 +1719,11 @@ dwarf2out_frame_debug_expr (rtx expr) /* Rule 4 */ if (REG_P (XEXP (src, 0)) && dwf_regno (XEXP (src, 0)) == cur_cfa->reg - && CONST_INT_P (XEXP (src, 1))) + && poly_int_rtx_p (XEXP (src, 1), &offset)) { /* Setting a temporary CFA register that will be copied into the FP later on. */ - offset = - INTVAL (XEXP (src, 1)); + offset = -offset; cur_cfa->offset += offset; cur_cfa->reg = dwf_regno (dest); /* Or used to save regs to the stack. */ @@ -1722,11 +1746,9 @@ dwarf2out_frame_debug_expr (rtx expr) /* Rule 9 */ else if (GET_CODE (src) == LO_SUM - && CONST_INT_P (XEXP (src, 1))) - { - cur_trace->cfa_temp.reg = dwf_regno (dest); - cur_trace->cfa_temp.offset = INTVAL (XEXP (src, 1)); - } + && poly_int_rtx_p (XEXP (src, 1), + &cur_trace->cfa_temp.offset)) + cur_trace->cfa_temp.reg = dwf_regno (dest); else gcc_unreachable (); } @@ -1734,8 +1756,9 @@ dwarf2out_frame_debug_expr (rtx expr) /* Rule 6 */ case CONST_INT: + case POLY_INT_CST: cur_trace->cfa_temp.reg = dwf_regno (dest); - cur_trace->cfa_temp.offset = INTVAL (src); + cur_trace->cfa_temp.offset = rtx_to_poly_int64 (src); break; /* Rule 7 */ @@ -1745,7 +1768,11 @@ dwarf2out_frame_debug_expr (rtx expr) && CONST_INT_P (XEXP (src, 1))); cur_trace->cfa_temp.reg = dwf_regno (dest); - cur_trace->cfa_temp.offset |= INTVAL (XEXP (src, 1)); + if (!can_ior_p (cur_trace->cfa_temp.offset, INTVAL (XEXP (src, 1)), + &cur_trace->cfa_temp.offset)) + /* The target shouldn't generate this kind of CFI note if we + can't represent it. */ + gcc_unreachable (); break; /* Skip over HIGH, assuming it will be followed by a LO_SUM, @@ -1800,9 +1827,7 @@ dwarf2out_frame_debug_expr (rtx expr) case PRE_MODIFY: case POST_MODIFY: /* We can't handle variable size modifications. */ - gcc_assert (GET_CODE (XEXP (XEXP (XEXP (dest, 0), 1), 1)) - == CONST_INT); - offset = -INTVAL (XEXP (XEXP (XEXP (dest, 0), 1), 1)); + offset = -rtx_to_poly_int64 (XEXP (XEXP (XEXP (dest, 0), 1), 1)); gcc_assert (REGNO (XEXP (XEXP (dest, 0), 0)) == STACK_POINTER_REGNUM && cur_trace->cfa_store.reg == dw_stack_pointer_regnum); @@ -1860,9 +1885,8 @@ dwarf2out_frame_debug_expr (rtx expr) { unsigned int regno; - gcc_assert (CONST_INT_P (XEXP (XEXP (dest, 0), 1)) - && REG_P (XEXP (XEXP (dest, 0), 0))); - offset = INTVAL (XEXP (XEXP (dest, 0), 1)); + gcc_assert (REG_P (XEXP (XEXP (dest, 0), 0))); + offset = rtx_to_poly_int64 (XEXP (XEXP (dest, 0), 1)); if (GET_CODE (XEXP (dest, 0)) == MINUS) offset = -offset; @@ -1923,7 +1947,7 @@ dwarf2out_frame_debug_expr (rtx expr) { /* We're storing the current CFA reg into the stack. */ - if (cur_cfa->offset == 0) + if (known_eq (cur_cfa->offset, 0)) { /* Rule 19 */ /* If stack is aligned, putting CFA reg into stack means @@ -1981,7 +2005,7 @@ dwarf2out_frame_debug_expr (rtx expr) { /* We have a PARALLEL describing where the contents of SRC live. Queue register saves for each piece of the PARALLEL. */ - HOST_WIDE_INT span_offset = offset; + poly_int64 span_offset = offset; gcc_assert (GET_CODE (span) == PARALLEL); @@ -2884,7 +2908,7 @@ static void initial_return_save (rtx rtl) { unsigned int reg = INVALID_REGNUM; - HOST_WIDE_INT offset = 0; + poly_int64 offset = 0; switch (GET_CODE (rtl)) { @@ -2905,12 +2929,12 @@ initial_return_save (rtx rtl) case PLUS: gcc_assert (REGNO (XEXP (rtl, 0)) == STACK_POINTER_REGNUM); - offset = INTVAL (XEXP (rtl, 1)); + offset = rtx_to_poly_int64 (XEXP (rtl, 1)); break; case MINUS: gcc_assert (REGNO (XEXP (rtl, 0)) == STACK_POINTER_REGNUM); - offset = -INTVAL (XEXP (rtl, 1)); + offset = -rtx_to_poly_int64 (XEXP (rtl, 1)); break; default: diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c index 88c947f14e7..63efe647053 100644 --- a/gcc/dwarf2out.c +++ b/gcc/dwarf2out.c @@ -573,6 +573,9 @@ dw_cfi_oprnd2_desc (enum dwarf_call_frame_info cfi) case DW_CFA_val_expression: return dw_cfi_oprnd_loc; + case DW_CFA_def_cfa_expression: + return dw_cfi_oprnd_cfa_loc; + default: return dw_cfi_oprnd_unused; } diff --git a/gcc/dwarf2out.h b/gcc/dwarf2out.h index 140724c8e8c..abaa9d03e11 100644 --- a/gcc/dwarf2out.h +++ b/gcc/dwarf2out.h @@ -43,7 +43,8 @@ enum dw_cfi_oprnd_type { dw_cfi_oprnd_reg_num, dw_cfi_oprnd_offset, dw_cfi_oprnd_addr, - dw_cfi_oprnd_loc + dw_cfi_oprnd_loc, + dw_cfi_oprnd_cfa_loc }; typedef union GTY(()) { @@ -51,6 +52,8 @@ typedef union GTY(()) { HOST_WIDE_INT GTY ((tag ("dw_cfi_oprnd_offset"))) dw_cfi_offset; const char * GTY ((tag ("dw_cfi_oprnd_addr"))) dw_cfi_addr; struct dw_loc_descr_node * GTY ((tag ("dw_cfi_oprnd_loc"))) dw_cfi_loc; + struct dw_cfa_location * GTY ((tag ("dw_cfi_oprnd_cfa_loc"))) + dw_cfi_cfa_loc; } dw_cfi_oprnd; struct GTY(()) dw_cfi_node { @@ -114,8 +117,8 @@ struct GTY(()) dw_fde_node { Instead of passing around REG and OFFSET, we pass a copy of this structure. */ struct GTY(()) dw_cfa_location { - HOST_WIDE_INT offset; - HOST_WIDE_INT base_offset; + poly_int64_pod offset; + poly_int64_pod base_offset; /* REG is in DWARF_FRAME_REGNUM space, *not* normal REGNO space. */ unsigned int reg; BOOL_BITFIELD indirect : 1; /* 1 if CFA is accessed via a dereference. */ diff --git a/gcc/gengtype.c b/gcc/gengtype.c index 64190ed69e0..e76d1fedef2 100644 --- a/gcc/gengtype.c +++ b/gcc/gengtype.c @@ -5192,6 +5192,7 @@ main (int argc, char **argv) POS_HERE (do_scalar_typedef ("REAL_VALUE_TYPE", &pos)); POS_HERE (do_scalar_typedef ("FIXED_VALUE_TYPE", &pos)); POS_HERE (do_scalar_typedef ("double_int", &pos)); + POS_HERE (do_scalar_typedef ("poly_int64_pod", &pos)); POS_HERE (do_scalar_typedef ("offset_int", &pos)); POS_HERE (do_scalar_typedef ("widest_int", &pos)); POS_HERE (do_scalar_typedef ("int64_t", &pos));