diff options
Diffstat (limited to 'gdb/symtab.c')
| -rw-r--r-- | gdb/symtab.c | 94 |
1 files changed, 59 insertions, 35 deletions
diff --git a/gdb/symtab.c b/gdb/symtab.c index 7f8877f..84e01a6 100644 --- a/gdb/symtab.c +++ b/gdb/symtab.c @@ -2441,12 +2441,13 @@ skip_prologue_sal (struct symtab_and_line *sal) struct symbol *sym; struct symtab_and_line start_sal; struct cleanup *old_chain; - CORE_ADDR pc; + CORE_ADDR pc, saved_pc; struct obj_section *section; const char *name; struct objfile *objfile; struct gdbarch *gdbarch; struct block *b, *function_block; + int force_skip, skip; /* Do not change the SAL is PC was specified explicitly. */ if (sal->explicit_pc) @@ -2484,46 +2485,69 @@ skip_prologue_sal (struct symtab_and_line *sal) gdbarch = get_objfile_arch (objfile); - /* If the function is in an unmapped overlay, use its unmapped LMA address, - so that gdbarch_skip_prologue has something unique to work on. */ - if (section_is_overlay (section) && !section_is_mapped (section)) - pc = overlay_unmapped_address (pc, section); + /* Process the prologue in two passes. In the first pass try to skip the + prologue (SKIP is true) and verify there is a real need for it (indicated + by FORCE_SKIP). If no such reason was found run a second pass where the + prologue is not skipped (SKIP is false). */ - /* Skip "first line" of function (which is actually its prologue). */ - pc += gdbarch_deprecated_function_start_offset (gdbarch); - pc = gdbarch_skip_prologue (gdbarch, pc); + skip = 1; + force_skip = 1; - /* For overlays, map pc back into its mapped VMA range. */ - pc = overlay_mapped_address (pc, section); + /* Be conservative - allow direct PC (without skipping prologue) only if we + have proven the CU (Compilation Unit) supports it. sal->SYMTAB does not + have to be set by the caller so we use SYM instead. */ + if (sym && SYMBOL_SYMTAB (sym)->locations_valid) + force_skip = 0; - /* Calculate line number. */ - start_sal = find_pc_sect_line (pc, section, 0); - - /* Check if gdbarch_skip_prologue left us in mid-line, and the next - line is still part of the same function. */ - if (start_sal.pc != pc - && (sym? (BLOCK_START (SYMBOL_BLOCK_VALUE (sym)) <= start_sal.end - && start_sal.end < BLOCK_END (SYMBOL_BLOCK_VALUE (sym))) - : (lookup_minimal_symbol_by_pc_section (start_sal.end, section) - == lookup_minimal_symbol_by_pc_section (pc, section)))) + saved_pc = pc; + do { - /* First pc of next line */ - pc = start_sal.end; - /* Recalculate the line number (might not be N+1). */ - start_sal = find_pc_sect_line (pc, section, 0); - } + pc = saved_pc; - /* On targets with executable formats that don't have a concept of - constructors (ELF with .init has, PE doesn't), gcc emits a call - to `__main' in `main' between the prologue and before user - code. */ - if (gdbarch_skip_main_prologue_p (gdbarch) - && name && strcmp (name, "main") == 0) - { - pc = gdbarch_skip_main_prologue (gdbarch, pc); - /* Recalculate the line number (might not be N+1). */ + /* If the function is in an unmapped overlay, use its unmapped LMA address, + so that gdbarch_skip_prologue has something unique to work on. */ + if (section_is_overlay (section) && !section_is_mapped (section)) + pc = overlay_unmapped_address (pc, section); + + /* Skip "first line" of function (which is actually its prologue). */ + pc += gdbarch_deprecated_function_start_offset (gdbarch); + if (skip) + pc = gdbarch_skip_prologue (gdbarch, pc); + + /* For overlays, map pc back into its mapped VMA range. */ + pc = overlay_mapped_address (pc, section); + + /* Calculate line number. */ start_sal = find_pc_sect_line (pc, section, 0); + + /* Check if gdbarch_skip_prologue left us in mid-line, and the next + line is still part of the same function. */ + if (skip && start_sal.pc != pc + && (sym? (BLOCK_START (SYMBOL_BLOCK_VALUE (sym)) <= start_sal.end + && start_sal.end < BLOCK_END (SYMBOL_BLOCK_VALUE (sym))) + : (lookup_minimal_symbol_by_pc_section (start_sal.end, section) + == lookup_minimal_symbol_by_pc_section (pc, section)))) + { + /* First pc of next line */ + pc = start_sal.end; + /* Recalculate the line number (might not be N+1). */ + start_sal = find_pc_sect_line (pc, section, 0); + } + + /* On targets with executable formats that don't have a concept of + constructors (ELF with .init has, PE doesn't), gcc emits a call + to `__main' in `main' between the prologue and before user + code. */ + if (gdbarch_skip_main_prologue_p (gdbarch) + && name && strcmp (name, "main") == 0) + { + pc = gdbarch_skip_main_prologue (gdbarch, pc); + /* Recalculate the line number (might not be N+1). */ + start_sal = find_pc_sect_line (pc, section, 0); + force_skip = 1; + } } + while (!force_skip && skip--); /* If we still don't have a valid source line, try to find the first PC in the lineinfo table that belongs to the same function. This @@ -2533,7 +2557,7 @@ skip_prologue_sal (struct symtab_and_line *sal) the case with the DJGPP target using "gcc -gcoff" when the compiler inserted code after the prologue to make sure the stack is aligned. */ - if (sym && start_sal.symtab == NULL) + if (!force_skip && sym && start_sal.symtab == NULL) { pc = skip_prologue_using_lineinfo (pc, SYMBOL_SYMTAB (sym)); /* Recalculate the line number. */ |