From 3b85b0f1a51c4badaf2c1603864294bd1d5c29f7 Mon Sep 17 00:00:00 2001 From: "Theodore A. Roth" Date: Wed, 16 Jul 2003 23:20:51 +0000 Subject: [PATCH] * avr-tdep.c (avr_skip_prologue): Return PC unchanged if no prologue found. (avr_frame_unwind_cache): Don't unwind FP for main. Update a comment. Save the computed prev_sp. (avr_saved_regs_unwinder): Remove function. (avr_frame_prev_register): Use PC unwind logic from avr_saved_regs_unwinder, otherwise use trad_frame_prev_register. --- gdb/ChangeLog | 11 +++++ gdb/avr-tdep.c | 134 +++++++++++++++++++++++++-------------------------------- 2 files changed, 69 insertions(+), 76 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 2d74ba2..35dab2e 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2003-07-16 Theodore A. Roth + + * avr-tdep.c (avr_skip_prologue): Return PC unchanged if no prologue + found. + (avr_frame_unwind_cache): Don't unwind FP for main. + Update a comment. + Save the computed prev_sp. + (avr_saved_regs_unwinder): Remove function. + (avr_frame_prev_register): Use PC unwind logic from + avr_saved_regs_unwinder(), otherwise use trad_frame_prev_register(). + 2003-07-16 Andrew Cagney * frame-base.h (frame_base_p_ftype): Delete definition. diff --git a/gdb/avr-tdep.c b/gdb/avr-tdep.c index 3e3d264..477aa82 100644 --- a/gdb/avr-tdep.c +++ b/gdb/avr-tdep.c @@ -796,7 +796,9 @@ avr_skip_prologue (CORE_ADDR pc) prologue_end = avr_scan_prologue (pc, &info); - if (info.prologue_type != AVR_PROLOGUE_NONE) + if (info.prologue_type == AVR_PROLOGUE_NONE) + return pc; + else { sal = find_pc_line (func_addr, 0); @@ -856,76 +858,6 @@ avr_extract_return_value (struct type *type, struct regcache *regcache, } } -static void -avr_saved_regs_unwinder (struct frame_info *next_frame, - struct trad_frame_saved_reg *this_saved_regs, - int regnum, int *optimizedp, - enum lval_type *lvalp, CORE_ADDR *addrp, - int *realnump, void *bufferp) -{ - if (this_saved_regs[regnum].addr != 0) - { - *optimizedp = 0; - *lvalp = lval_memory; - *addrp = this_saved_regs[regnum].addr; - *realnump = -1; - if (bufferp != NULL) - { - /* Read the value in from memory. */ - - if (regnum == AVR_PC_REGNUM) - { - /* Reading the return PC from the PC register is slightly - abnormal. register_size(AVR_PC_REGNUM) says it is 4 bytes, - but in reality, only two bytes (3 in upcoming mega256) are - stored on the stack. - - Also, note that the value on the stack is an addr to a word - not a byte, so we will need to multiply it by two at some - point. - - And to confuse matters even more, the return address stored - on the stack is in big endian byte order, even though most - everything else about the avr is little endian. Ick! */ - - /* FIXME: number of bytes read here will need updated for the - mega256 when it is available. */ - - ULONGEST pc; - unsigned char tmp; - unsigned char buf[2]; - - read_memory (this_saved_regs[regnum].addr, buf, 2); - - /* Convert the PC read from memory as a big-endian to - little-endian order. */ - tmp = buf[0]; - buf[0] = buf[1]; - buf[1] = tmp; - - pc = (extract_unsigned_integer (buf, 2) * 2); - store_unsigned_integer (bufferp, - register_size (current_gdbarch, regnum), - pc); - } - else - { - read_memory (this_saved_regs[regnum].addr, bufferp, - register_size (current_gdbarch, regnum)); - } - } - - return; - } - - /* No luck, assume this and the next frame have the same register - value. If a value is needed, pass the request on down the chain; - otherwise just return an indication that the value is in the same - register as the next frame. */ - frame_register_unwind (next_frame, regnum, optimizedp, lvalp, addrp, - realnump, bufferp); -} - /* Put here the code to store, into fi->saved_regs, the addresses of the saved registers of frame described by FRAME_INFO. This includes special registers such as pc and fp saved in special ways @@ -957,7 +889,8 @@ avr_frame_unwind_cache (struct frame_info *next_frame, if ((pc > 0) && (pc < frame_pc_unwind (next_frame))) avr_scan_prologue (pc, info); - if (info->prologue_type != AVR_PROLOGUE_NONE) + if ((info->prologue_type != AVR_PROLOGUE_NONE) + && (info->prologue_type != AVR_PROLOGUE_MAIN)) { ULONGEST high_base; /* High byte of FP */ @@ -987,8 +920,7 @@ avr_frame_unwind_cache (struct frame_info *next_frame, info->base = avr_make_saddr (this_base); /* Adjust all the saved registers so that they contain addresses and not - offsets. We need to add one to the addresses since push ops are post - decrement on the avr. */ + offsets. */ for (i = 0; i < NUM_REGS - 1; i++) if (info->saved_regs[i].addr) { @@ -1003,6 +935,10 @@ avr_frame_unwind_cache (struct frame_info *next_frame, info->saved_regs[AVR_PC_REGNUM].addr = info->prev_sp; } + /* The previous frame's SP needed to be computed. Save the computed + value. */ + trad_frame_set_value (info->saved_regs, AVR_SP_REGNUM, info->prev_sp+1); + return info; } @@ -1069,8 +1005,54 @@ avr_frame_prev_register (struct frame_info *next_frame, struct avr_unwind_cache *info = avr_frame_unwind_cache (next_frame, this_prologue_cache); - avr_saved_regs_unwinder (next_frame, info->saved_regs, regnum, optimizedp, - lvalp, addrp, realnump, bufferp); + if (regnum == AVR_PC_REGNUM) + { + if (trad_frame_addr_p (info->saved_regs, regnum)) + { + *optimizedp = 0; + *lvalp = lval_memory; + *addrp = info->saved_regs[regnum].addr; + *realnump = -1; + if (bufferp != NULL) + { + /* Reading the return PC from the PC register is slightly + abnormal. register_size(AVR_PC_REGNUM) says it is 4 bytes, + but in reality, only two bytes (3 in upcoming mega256) are + stored on the stack. + + Also, note that the value on the stack is an addr to a word + not a byte, so we will need to multiply it by two at some + point. + + And to confuse matters even more, the return address stored + on the stack is in big endian byte order, even though most + everything else about the avr is little endian. Ick! */ + + /* FIXME: number of bytes read here will need updated for the + mega256 when it is available. */ + + ULONGEST pc; + unsigned char tmp; + unsigned char buf[2]; + + read_memory (info->saved_regs[regnum].addr, buf, 2); + + /* Convert the PC read from memory as a big-endian to + little-endian order. */ + tmp = buf[0]; + buf[0] = buf[1]; + buf[1] = tmp; + + pc = (extract_unsigned_integer (buf, 2) * 2); + store_unsigned_integer (bufferp, + register_size (current_gdbarch, regnum), + pc); + } + } + } + else + trad_frame_prev_register (next_frame, info->saved_regs, regnum, + optimizedp, lvalp, addrp, realnump, bufferp); } static const struct frame_unwind avr_frame_unwind = { -- 2.7.4