X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fdwarf2expr.c;h=5e27d381f492b182d480ab05c879e8537ae31f21;hb=93c26624a73822b9e864c84e0d3ce93a2e79e5cf;hp=ab2b109dfa620898655ee98435be3b2f2f34b4b6;hpb=17a912b6825ef7feaad6d9b4f5419f045fe3c8d0;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/dwarf2expr.c b/gdb/dwarf2expr.c index ab2b109dfa..5e27d381f4 100644 --- a/gdb/dwarf2expr.c +++ b/gdb/dwarf2expr.c @@ -1,6 +1,7 @@ /* DWARF 2 Expression Evaluator. - Copyright (C) 2001, 2002, 2003, 2005, 2007 Free Software Foundation, Inc. + Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010 + Free Software Foundation, Inc. Contributed by Daniel Berlin (dan@dberlin.org) @@ -8,7 +9,7 @@ This program 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 of the License, or + the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, @@ -17,23 +18,22 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 51 Franklin Street, Fifth Floor, - Boston, MA 02110-1301, USA. */ + along with this program. If not, see . */ #include "defs.h" #include "symtab.h" #include "gdbtypes.h" #include "value.h" #include "gdbcore.h" -#include "elf/dwarf2.h" +#include "dwarf2.h" #include "dwarf2expr.h" +#include "gdb_assert.h" /* Local prototypes. */ static void execute_stack_op (struct dwarf_expr_context *, gdb_byte *, gdb_byte *); -static struct type *unsigned_address_type (void); +static struct type *unsigned_address_type (struct gdbarch *, int); /* Create a new context for the expression evaluator. */ @@ -47,6 +47,7 @@ new_dwarf_expr_context (void) retval->stack = xmalloc (retval->stack_allocated * sizeof (CORE_ADDR)); retval->num_pieces = 0; retval->pieces = 0; + retval->max_recursion_depth = 0x100; return retval; } @@ -60,6 +61,22 @@ free_dwarf_expr_context (struct dwarf_expr_context *ctx) xfree (ctx); } +/* Helper for make_cleanup_free_dwarf_expr_context. */ + +static void +free_dwarf_expr_context_cleanup (void *arg) +{ + free_dwarf_expr_context (arg); +} + +/* Return a cleanup that calls free_dwarf_expr_context. */ + +struct cleanup * +make_cleanup_free_dwarf_expr_context (struct dwarf_expr_context *ctx) +{ + return make_cleanup (free_dwarf_expr_context_cleanup, ctx); +} + /* Expand the memory allocated to CTX's stack to contain at least NEED more elements than are currently used. */ @@ -70,7 +87,7 @@ dwarf_expr_grow_stack (struct dwarf_expr_context *ctx, size_t need) { size_t newlen = ctx->stack_len + need + 10; ctx->stack = xrealloc (ctx->stack, - newlen * sizeof (CORE_ADDR)); + newlen * sizeof (struct dwarf_stack_value)); ctx->stack_allocated = newlen; } } @@ -78,10 +95,15 @@ dwarf_expr_grow_stack (struct dwarf_expr_context *ctx, size_t need) /* Push VALUE onto CTX's stack. */ void -dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value) +dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value, + int in_stack_memory) { + struct dwarf_stack_value *v; + dwarf_expr_grow_stack (ctx, 1); - ctx->stack[ctx->stack_len++] = value; + v = &ctx->stack[ctx->stack_len++]; + v->value = value; + v->in_stack_memory = in_stack_memory; } /* Pop the top item off of CTX's stack. */ @@ -102,14 +124,25 @@ dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n) if (ctx->stack_len <= n) error (_("Asked for position %d of stack, stack only has %d elements on it."), n, ctx->stack_len); - return ctx->stack[ctx->stack_len - (1 + n)]; + return ctx->stack[ctx->stack_len - (1 + n)].value; + +} + +/* Retrieve the in_stack_memory flag of the N'th item on CTX's stack. */ + +int +dwarf_expr_fetch_in_stack_memory (struct dwarf_expr_context *ctx, int n) +{ + if (ctx->stack_len <= n) + error (_("Asked for position %d of stack, stack only has %d elements on it."), + n, ctx->stack_len); + return ctx->stack[ctx->stack_len - (1 + n)].in_stack_memory; } /* Add a new piece to CTX's piece list. */ static void -add_piece (struct dwarf_expr_context *ctx, - int in_reg, CORE_ADDR value, ULONGEST size) +add_piece (struct dwarf_expr_context *ctx, ULONGEST size) { struct dwarf_expr_piece *p; @@ -124,9 +157,18 @@ add_piece (struct dwarf_expr_context *ctx, * sizeof (struct dwarf_expr_piece)); p = &ctx->pieces[ctx->num_pieces - 1]; - p->in_reg = in_reg; - p->value = value; + p->location = ctx->location; p->size = size; + if (p->location == DWARF_VALUE_LITERAL) + { + p->v.literal.data = ctx->data; + p->v.literal.length = ctx->len; + } + else + { + p->v.expr.value = dwarf_expr_fetch (ctx, 0); + p->v.expr.in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0); + } } /* Evaluate the expression at ADDR (LEN bytes long) using the context @@ -135,7 +177,13 @@ add_piece (struct dwarf_expr_context *ctx, void dwarf_expr_eval (struct dwarf_expr_context *ctx, gdb_byte *addr, size_t len) { + int old_recursion_depth = ctx->recursion_depth; + execute_stack_op (ctx, addr, addr + len); + + /* CTX RECURSION_DEPTH becomes invalid if an exception was thrown here. */ + + gdb_assert (ctx->recursion_depth == old_recursion_depth); } /* Decode the unsigned LEB128 constant at BUF into the variable pointed to @@ -193,90 +241,94 @@ read_sleb128 (gdb_byte *buf, gdb_byte *buf_end, LONGEST * r) return buf; } -/* Read an address from BUF, and verify that it doesn't extend past - BUF_END. The address is returned, and *BYTES_READ is set to the - number of bytes read from BUF. */ +/* Read an address of size ADDR_SIZE from BUF, and verify that it + doesn't extend past BUF_END. */ CORE_ADDR -dwarf2_read_address (gdb_byte *buf, gdb_byte *buf_end, int *bytes_read) +dwarf2_read_address (struct gdbarch *gdbarch, gdb_byte *buf, + gdb_byte *buf_end, int addr_size) { + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); CORE_ADDR result; - if (buf_end - buf < gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT) + if (buf_end - buf < addr_size) error (_("dwarf2_read_address: Corrupted DWARF expression.")); - *bytes_read = gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT; - /* For most architectures, calling extract_unsigned_integer() alone is sufficient for extracting an address. However, some architectures (e.g. MIPS) use signed addresses and using extract_unsigned_integer() will not produce a correct - result. Turning the unsigned integer into a value and then - decomposing that value as an address will cause - gdbarch_integer_to_address() to be invoked for those - architectures which require it. Thus, using value_as_address() - will produce the correct result for both types of architectures. - - One concern regarding the use of values for this purpose is - efficiency. Obviously, these extra calls will take more time to - execute and creating a value takes more space, space which will - have to be garbage collected at a later time. If constructing - and then decomposing a value for this purpose proves to be too - inefficient, then gdbarch_integer_to_address() can be called - directly. + result. Make sure we invoke gdbarch_integer_to_address() + for those architectures which require it. The use of `unsigned_address_type' in the code below refers to the type of buf and has no bearing on the signedness of the address being returned. */ - result = value_as_address (value_from_longest - (unsigned_address_type (), - extract_unsigned_integer - (buf, - gdbarch_addr_bit (current_gdbarch) - / TARGET_CHAR_BIT))); + if (gdbarch_integer_to_address_p (gdbarch)) + return gdbarch_integer_to_address + (gdbarch, unsigned_address_type (gdbarch, addr_size), buf); - return result; + return extract_unsigned_integer (buf, addr_size, byte_order); } -/* Return the type of an address, for unsigned arithmetic. */ +/* Return the type of an address of size ADDR_SIZE, + for unsigned arithmetic. */ static struct type * -unsigned_address_type (void) +unsigned_address_type (struct gdbarch *gdbarch, int addr_size) { - switch (gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT) + switch (addr_size) { case 2: - return builtin_type_uint16; + return builtin_type (gdbarch)->builtin_uint16; case 4: - return builtin_type_uint32; + return builtin_type (gdbarch)->builtin_uint32; case 8: - return builtin_type_uint64; + return builtin_type (gdbarch)->builtin_uint64; default: internal_error (__FILE__, __LINE__, _("Unsupported address size.\n")); } } -/* Return the type of an address, for signed arithmetic. */ +/* Return the type of an address of size ADDR_SIZE, + for signed arithmetic. */ static struct type * -signed_address_type (void) +signed_address_type (struct gdbarch *gdbarch, int addr_size) { - switch (gdbarch_addr_bit (current_gdbarch) / TARGET_CHAR_BIT) + switch (addr_size) { case 2: - return builtin_type_int16; + return builtin_type (gdbarch)->builtin_int16; case 4: - return builtin_type_int32; + return builtin_type (gdbarch)->builtin_int32; case 8: - return builtin_type_int64; + return builtin_type (gdbarch)->builtin_int64; default: internal_error (__FILE__, __LINE__, _("Unsupported address size.\n")); } } + +/* Check that the current operator is either at the end of an + expression, or that it is followed by a composition operator. */ + +static void +require_composition (gdb_byte *op_ptr, gdb_byte *op_end, const char *op_name) +{ + /* It seems like DW_OP_GNU_uninit should be handled here. However, + it doesn't seem to make sense for DW_OP_*_value, and it was not + checked at the other place that this function is called. */ + if (op_ptr != op_end && *op_ptr != DW_OP_piece && *op_ptr != DW_OP_bit_piece) + error (_("DWARF-2 expression error: `%s' operations must be " + "used either alone or in conjuction with DW_OP_piece " + "or DW_OP_bit_piece."), + op_name); +} + /* The engine for the expression evaluator. Using the context in CTX, evaluate the expression between OP_PTR and OP_END. */ @@ -284,16 +336,28 @@ static void execute_stack_op (struct dwarf_expr_context *ctx, gdb_byte *op_ptr, gdb_byte *op_end) { - ctx->in_reg = 0; + enum bfd_endian byte_order = gdbarch_byte_order (ctx->gdbarch); + ctx->location = DWARF_VALUE_MEMORY; ctx->initialized = 1; /* Default is initialized. */ + if (ctx->recursion_depth > ctx->max_recursion_depth) + error (_("DWARF-2 expression error: Loop detected (%d)."), + ctx->recursion_depth); + ctx->recursion_depth++; + while (op_ptr < op_end) { enum dwarf_location_atom op = *op_ptr++; CORE_ADDR result; + /* Assume the value is not in stack memory. + Code that knows otherwise sets this to 1. + Some arithmetic on stack addresses can probably be assumed to still + be a stack address, but we skip this complication for now. + This is just an optimization, so it's always ok to punt + and leave this as 0. */ + int in_stack_memory = 0; ULONGEST uoffset, reg; LONGEST offset; - int bytes_read; switch (op) { @@ -333,40 +397,41 @@ execute_stack_op (struct dwarf_expr_context *ctx, break; case DW_OP_addr: - result = dwarf2_read_address (op_ptr, op_end, &bytes_read); - op_ptr += bytes_read; + result = dwarf2_read_address (ctx->gdbarch, + op_ptr, op_end, ctx->addr_size); + op_ptr += ctx->addr_size; break; case DW_OP_const1u: - result = extract_unsigned_integer (op_ptr, 1); + result = extract_unsigned_integer (op_ptr, 1, byte_order); op_ptr += 1; break; case DW_OP_const1s: - result = extract_signed_integer (op_ptr, 1); + result = extract_signed_integer (op_ptr, 1, byte_order); op_ptr += 1; break; case DW_OP_const2u: - result = extract_unsigned_integer (op_ptr, 2); + result = extract_unsigned_integer (op_ptr, 2, byte_order); op_ptr += 2; break; case DW_OP_const2s: - result = extract_signed_integer (op_ptr, 2); + result = extract_signed_integer (op_ptr, 2, byte_order); op_ptr += 2; break; case DW_OP_const4u: - result = extract_unsigned_integer (op_ptr, 4); + result = extract_unsigned_integer (op_ptr, 4, byte_order); op_ptr += 4; break; case DW_OP_const4s: - result = extract_signed_integer (op_ptr, 4); + result = extract_signed_integer (op_ptr, 4, byte_order); op_ptr += 4; break; case DW_OP_const8u: - result = extract_unsigned_integer (op_ptr, 8); + result = extract_unsigned_integer (op_ptr, 8, byte_order); op_ptr += 8; break; case DW_OP_const8s: - result = extract_signed_integer (op_ptr, 8); + result = extract_signed_integer (op_ptr, 8, byte_order); op_ptr += 8; break; case DW_OP_constu: @@ -419,20 +484,36 @@ execute_stack_op (struct dwarf_expr_context *ctx, "used either alone or in conjuction with DW_OP_piece.")); result = op - DW_OP_reg0; - ctx->in_reg = 1; - + ctx->location = DWARF_VALUE_REGISTER; break; case DW_OP_regx: op_ptr = read_uleb128 (op_ptr, op_end, ®); - if (op_ptr != op_end && *op_ptr != DW_OP_piece) - error (_("DWARF-2 expression error: DW_OP_reg operations must be " - "used either alone or in conjuction with DW_OP_piece.")); + require_composition (op_ptr, op_end, "DW_OP_regx"); result = reg; - ctx->in_reg = 1; + ctx->location = DWARF_VALUE_REGISTER; break; + case DW_OP_implicit_value: + { + ULONGEST len; + op_ptr = read_uleb128 (op_ptr, op_end, &len); + if (op_ptr + len > op_end) + error (_("DW_OP_implicit_value: too few bytes available.")); + ctx->len = len; + ctx->data = op_ptr; + ctx->location = DWARF_VALUE_LITERAL; + op_ptr += len; + require_composition (op_ptr, op_end, "DW_OP_implicit_value"); + } + goto no_push; + + case DW_OP_stack_value: + ctx->location = DWARF_VALUE_STACK; + require_composition (op_ptr, op_end, "DW_OP_stack_value"); + goto no_push; + case DW_OP_breg0: case DW_OP_breg1: case DW_OP_breg2: @@ -496,16 +577,22 @@ execute_stack_op (struct dwarf_expr_context *ctx, specific this_base method. */ (ctx->get_frame_base) (ctx->baton, &datastart, &datalen); dwarf_expr_eval (ctx, datastart, datalen); + if (ctx->location == DWARF_VALUE_LITERAL + || ctx->location == DWARF_VALUE_STACK) + error (_("Not implemented: computing frame base using explicit value operator")); result = dwarf_expr_fetch (ctx, 0); - if (ctx->in_reg) + if (ctx->location == DWARF_VALUE_REGISTER) result = (ctx->read_reg) (ctx->baton, result); result = result + offset; + in_stack_memory = 1; ctx->stack_len = before_stack_len; - ctx->in_reg = 0; + ctx->location = DWARF_VALUE_MEMORY; } break; + case DW_OP_dup: result = dwarf_expr_fetch (ctx, 0); + in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0); break; case DW_OP_drop: @@ -515,15 +602,31 @@ execute_stack_op (struct dwarf_expr_context *ctx, case DW_OP_pick: offset = *op_ptr++; result = dwarf_expr_fetch (ctx, offset); + in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, offset); break; + + case DW_OP_swap: + { + struct dwarf_stack_value t1, t2; + + if (ctx->stack_len < 2) + error (_("Not enough elements for DW_OP_swap. Need 2, have %d."), + ctx->stack_len); + t1 = ctx->stack[ctx->stack_len - 1]; + t2 = ctx->stack[ctx->stack_len - 2]; + ctx->stack[ctx->stack_len - 1] = t2; + ctx->stack[ctx->stack_len - 2] = t1; + goto no_push; + } case DW_OP_over: result = dwarf_expr_fetch (ctx, 1); + in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 1); break; case DW_OP_rot: { - CORE_ADDR t1, t2, t3; + struct dwarf_stack_value t1, t2, t3; if (ctx->stack_len < 3) error (_("Not enough elements for DW_OP_rot. Need 3, have %d."), @@ -551,34 +654,22 @@ execute_stack_op (struct dwarf_expr_context *ctx, { case DW_OP_deref: { - gdb_byte *buf = alloca (gdbarch_addr_bit (current_gdbarch) - / TARGET_CHAR_BIT); - int bytes_read; - - (ctx->read_mem) (ctx->baton, buf, result, - gdbarch_addr_bit (current_gdbarch) - / TARGET_CHAR_BIT); - result = dwarf2_read_address (buf, - buf + (gdbarch_addr_bit - (current_gdbarch) - / TARGET_CHAR_BIT), - &bytes_read); + gdb_byte *buf = alloca (ctx->addr_size); + (ctx->read_mem) (ctx->baton, buf, result, ctx->addr_size); + result = dwarf2_read_address (ctx->gdbarch, + buf, buf + ctx->addr_size, + ctx->addr_size); } break; case DW_OP_deref_size: { - gdb_byte *buf - = alloca (gdbarch_addr_bit (current_gdbarch) - / TARGET_CHAR_BIT); - int bytes_read; - - (ctx->read_mem) (ctx->baton, buf, result, *op_ptr++); - result = dwarf2_read_address (buf, - buf + (gdbarch_addr_bit - (current_gdbarch) - / TARGET_CHAR_BIT), - &bytes_read); + int addr_size = *op_ptr++; + gdb_byte *buf = alloca (addr_size); + (ctx->read_mem) (ctx->baton, buf, result, addr_size); + result = dwarf2_read_address (ctx->gdbarch, + buf, buf + addr_size, + addr_size); } break; @@ -622,6 +713,7 @@ execute_stack_op (struct dwarf_expr_context *ctx, CORE_ADDR first, second; enum exp_opcode binop; struct value *val1, *val2; + struct type *stype, *utype; second = dwarf_expr_fetch (ctx, 0); dwarf_expr_pop (ctx); @@ -629,8 +721,10 @@ execute_stack_op (struct dwarf_expr_context *ctx, first = dwarf_expr_fetch (ctx, 0); dwarf_expr_pop (ctx); - val1 = value_from_longest (unsigned_address_type (), first); - val2 = value_from_longest (unsigned_address_type (), second); + utype = unsigned_address_type (ctx->gdbarch, ctx->addr_size); + stype = signed_address_type (ctx->gdbarch, ctx->addr_size); + val1 = value_from_longest (utype, first); + val2 = value_from_longest (utype, second); switch (op) { @@ -663,7 +757,7 @@ execute_stack_op (struct dwarf_expr_context *ctx, break; case DW_OP_shra: binop = BINOP_RSH; - val1 = value_from_longest (signed_address_type (), first); + val1 = value_from_longest (stype, first); break; case DW_OP_xor: binop = BINOP_BITWISE_XOR; @@ -694,6 +788,11 @@ execute_stack_op (struct dwarf_expr_context *ctx, } break; + case DW_OP_call_frame_cfa: + result = (ctx->get_frame_cfa) (ctx->baton); + in_stack_memory = 1; + break; + case DW_OP_GNU_push_tls_address: /* Variable is at a constant offset in the thread-local storage block into the objfile for the current thread and @@ -709,13 +808,13 @@ execute_stack_op (struct dwarf_expr_context *ctx, break; case DW_OP_skip: - offset = extract_signed_integer (op_ptr, 2); + offset = extract_signed_integer (op_ptr, 2, byte_order); op_ptr += 2; op_ptr += offset; goto no_push; case DW_OP_bra: - offset = extract_signed_integer (op_ptr, 2); + offset = extract_signed_integer (op_ptr, 2, byte_order); op_ptr += 2; if (dwarf_expr_fetch (ctx, 0) != 0) op_ptr += offset; @@ -728,22 +827,22 @@ execute_stack_op (struct dwarf_expr_context *ctx, case DW_OP_piece: { ULONGEST size; - CORE_ADDR addr_or_regnum; /* Record the piece. */ op_ptr = read_uleb128 (op_ptr, op_end, &size); - addr_or_regnum = dwarf_expr_fetch (ctx, 0); - add_piece (ctx, ctx->in_reg, addr_or_regnum, size); + add_piece (ctx, size); - /* Pop off the address/regnum, and clear the in_reg flag. */ - dwarf_expr_pop (ctx); - ctx->in_reg = 0; + /* Pop off the address/regnum, and reset the location + type. */ + if (ctx->location != DWARF_VALUE_LITERAL) + dwarf_expr_pop (ctx); + ctx->location = DWARF_VALUE_MEMORY; } goto no_push; case DW_OP_GNU_uninit: if (op_ptr != op_end) - error (_("DWARF-2 expression error: DW_OP_GNU_unint must always " + error (_("DWARF-2 expression error: DW_OP_GNU_uninit must always " "be the very last op.")); ctx->initialized = 0; @@ -754,7 +853,10 @@ execute_stack_op (struct dwarf_expr_context *ctx, } /* Most things push a result value. */ - dwarf_expr_push (ctx, result); + dwarf_expr_push (ctx, result, in_stack_memory); no_push:; } + + ctx->recursion_depth--; + gdb_assert (ctx->recursion_depth >= 0); }