From f622ea96de49d77646f52501ef00d03132fcb2df Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Fri, 13 Jan 2017 12:21:22 +0000 Subject: [PATCH] Remove magic numbers in m68k-dis.c:print_insn_arg When I inspect the return values of disassmblers, I happen to see various -1/-2/-3 magic numbers are used in m68k-dis.c. This patch is to replace them with enum. -1 and -2 is "clearly documented" in print_ins_arg's comments, but -3 isn't. In fact, -3 is returned when FETCH_DATA returns false, which means memory error (because fetch_data return 0 on memory error). So I name enum PRINT_INSN_ARG_MEMORY_ERROR for -3. This patch is a refactor patch, doesn't affect any functionality. opcodes: 2017-01-13 Yao Qi * m68k-dis.c (enum print_insn_arg_error): New. (NEXTBYTE): Replace -3 with PRINT_INSN_ARG_MEMORY_ERROR. (NEXTULONG): Likewise. (NEXTSINGLE): Likewise. (NEXTDOUBLE): Likewise. (NEXTDOUBLE): Likewise. (NEXTPACKED): Likewise. (FETCH_ARG): Likewise. (FETCH_DATA): Update comments. (print_insn_arg): Update comments. Replace magic numbers with enum. (match_insn_m68k): Likewise. --- opcodes/ChangeLog | 16 +++++++++ opcodes/m68k-dis.c | 97 +++++++++++++++++++++++++++++++----------------------- 2 files changed, 72 insertions(+), 41 deletions(-) diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog index 000948e..0adbdf1 100644 --- a/opcodes/ChangeLog +++ b/opcodes/ChangeLog @@ -1,3 +1,19 @@ +2017-01-13 Yao Qi + + * m68k-dis.c (enum print_insn_arg_error): New. + (NEXTBYTE): Replace -3 with + PRINT_INSN_ARG_MEMORY_ERROR. + (NEXTULONG): Likewise. + (NEXTSINGLE): Likewise. + (NEXTDOUBLE): Likewise. + (NEXTDOUBLE): Likewise. + (NEXTPACKED): Likewise. + (FETCH_ARG): Likewise. + (FETCH_DATA): Update comments. + (print_insn_arg): Update comments. Replace magic numbers with + enum. + (match_insn_m68k): Likewise. + 2017-01-12 Igor Tsimbalist * i386-dis.c (enum): Add PREFIX_EVEX_0F3855, EVEX_W_0F3855_P_2. diff --git a/opcodes/m68k-dis.c b/opcodes/m68k-dis.c index de88f23..a14db9a 100644 --- a/opcodes/m68k-dis.c +++ b/opcodes/m68k-dis.c @@ -57,13 +57,27 @@ static char *const reg_half_names[] = #define COERCE_SIGNED_CHAR(ch) ((int) (((ch) ^ 0x80) & 0xFF) - 128) #endif +/* Error code of print_insn_arg's return value. */ + +enum print_insn_arg_error + { + /* An invalid operand is found. */ + PRINT_INSN_ARG_INVALID_OPERAND = -1, + + /* An opcode table error. */ + PRINT_INSN_ARG_INVALID_OP_TABLE = -2, + + /* A memory error. */ + PRINT_INSN_ARG_MEMORY_ERROR = -3, + }; + /* Get a 1 byte signed integer. */ #define NEXTBYTE(p, val) \ do \ { \ p += 2; \ if (!FETCH_DATA (info, p)) \ - return -3; \ + return PRINT_INSN_ARG_MEMORY_ERROR; \ val = COERCE_SIGNED_CHAR (p[-1]); \ } \ while (0) @@ -100,7 +114,7 @@ static char *const reg_half_names[] = { \ p += 4; \ if (!FETCH_DATA (info, p)) \ - return -3; \ + return PRINT_INSN_ARG_MEMORY_ERROR; \ val = (unsigned int) ((((((p[-4] << 8) + p[-3]) << 8) + p[-2]) << 8) + p[-1]); \ } \ while (0) @@ -111,7 +125,7 @@ static char *const reg_half_names[] = { \ p += 4; \ if (!FETCH_DATA (info, p)) \ - return -3; \ + return PRINT_INSN_ARG_MEMORY_ERROR; \ floatformat_to_double (& floatformat_ieee_single_big, \ (char *) p - 4, & val); \ } \ @@ -123,7 +137,7 @@ static char *const reg_half_names[] = { \ p += 8; \ if (!FETCH_DATA (info, p)) \ - return -3; \ + return PRINT_INSN_ARG_MEMORY_ERROR; \ floatformat_to_double (& floatformat_ieee_double_big, \ (char *) p - 8, & val); \ } \ @@ -135,7 +149,7 @@ static char *const reg_half_names[] = { \ p += 12; \ if (!FETCH_DATA (info, p)) \ - return -3; \ + return PRINT_INSN_ARG_MEMORY_ERROR; \ floatformat_to_double (& floatformat_m68881_ext, \ (char *) p - 12, & val); \ } \ @@ -150,7 +164,7 @@ static char *const reg_half_names[] = { \ p += 12; \ if (!FETCH_DATA (info, p)) \ - return -3; \ + return PRINT_INSN_ARG_MEMORY_ERROR; \ val = 0.0; \ } \ while (0) @@ -168,7 +182,8 @@ struct private }; /* Make sure that bytes from INFO->PRIVATE_DATA->BUFFER (inclusive) - to ADDR (exclusive) are valid. Returns 1 for success, 0 on error. */ + to ADDR (exclusive) are valid. Returns 1 for success, 0 on memory + error. */ #define FETCH_DATA(info, addr) \ ((addr) <= ((struct private *) (info->private_data))->max_fetched \ ? 1 : fetch_data ((info), (addr))) @@ -617,14 +632,13 @@ print_indexed (int basereg, { \ val = fetch_arg (buffer, place, size, info); \ if (val < 0) \ - return -3; \ + return PRINT_INSN_ARG_MEMORY_ERROR; \ } \ while (0) /* Returns number of bytes "eaten" by the operand, or - return -1 if an invalid operand was found, or -2 if - an opcode tabe error was found or -3 to simply abort. - ADDR is the pc for this arg to be relative to. */ + return enum print_insn_arg_error. ADDR is the pc for this arg to be + relative to. */ static int print_insn_arg (const char *d, @@ -864,7 +878,7 @@ print_insn_arg (const char *d, (*info->fprintf_func) (info->stream, "{#%d}", val); } else - return -1; + return PRINT_INSN_ARG_INVALID_OPERAND; break; case '#': @@ -881,11 +895,11 @@ print_insn_arg (const char *d, else if (place == 'b') NEXTBYTE (p1, val); else if (place == 'w' || place == 'W') - NEXTWORD (p1, val, -3); + NEXTWORD (p1, val, PRINT_INSN_ARG_MEMORY_ERROR); else if (place == 'l') - NEXTLONG (p1, val, -3); + NEXTLONG (p1, val, PRINT_INSN_ARG_MEMORY_ERROR); else - return -2; + return PRINT_INSN_ARG_INVALID_OP_TABLE; (*info->fprintf_func) (info->stream, "#%d", val); break; @@ -896,26 +910,26 @@ print_insn_arg (const char *d, else if (place == 'B') disp = COERCE_SIGNED_CHAR (buffer[1]); else if (place == 'w' || place == 'W') - NEXTWORD (p, disp, -3); + NEXTWORD (p, disp, PRINT_INSN_ARG_MEMORY_ERROR); else if (place == 'l' || place == 'L' || place == 'C') - NEXTLONG (p, disp, -3); + NEXTLONG (p, disp, PRINT_INSN_ARG_MEMORY_ERROR); else if (place == 'g') { NEXTBYTE (buffer, disp); if (disp == 0) - NEXTWORD (p, disp, -3); + NEXTWORD (p, disp, PRINT_INSN_ARG_MEMORY_ERROR); else if (disp == -1) - NEXTLONG (p, disp, -3); + NEXTLONG (p, disp, PRINT_INSN_ARG_MEMORY_ERROR); } else if (place == 'c') { if (buffer[1] & 0x40) /* If bit six is one, long offset. */ - NEXTLONG (p, disp, -3); + NEXTLONG (p, disp, PRINT_INSN_ARG_MEMORY_ERROR); else - NEXTWORD (p, disp, -3); + NEXTWORD (p, disp, PRINT_INSN_ARG_MEMORY_ERROR); } else - return -2; + return PRINT_INSN_ARG_INVALID_OP_TABLE; (*info->print_address_func) (addr + disp, info); break; @@ -924,7 +938,7 @@ print_insn_arg (const char *d, { int val1; - NEXTWORD (p, val, -3); + NEXTWORD (p, val, PRINT_INSN_ARG_MEMORY_ERROR); FETCH_ARG (3, val1); (*info->fprintf_func) (info->stream, "%s@(%d)", reg_names[val1 + 8], val); break; @@ -952,14 +966,14 @@ print_insn_arg (const char *d, else if (val == 3) (*info->fprintf_func) (info->stream, ">>"); else - return -1; + return PRINT_INSN_ARG_INVALID_OPERAND; break; case 'I': /* Get coprocessor ID... */ val = fetch_arg (buffer, 'd', 3, info); if (val < 0) - return -3; + return PRINT_INSN_ARG_MEMORY_ERROR; if (val != 1) /* Unusual coprocessor ID? */ (*info->fprintf_func) (info->stream, "(cpid=%d) ", val); break; @@ -992,19 +1006,19 @@ print_insn_arg (const char *d, { val = fetch_arg (buffer, 'x', 6, info); if (val < 0) - return -3; + return PRINT_INSN_ARG_MEMORY_ERROR; val = ((val & 7) << 3) + ((val >> 3) & 7); } else { val = fetch_arg (buffer, 's', 6, info); if (val < 0) - return -3; + return PRINT_INSN_ARG_MEMORY_ERROR; } /* If the is invalid for *d, then reject this match. */ if (!m68k_valid_ea (*d, val)) - return -1; + return PRINT_INSN_ARG_INVALID_OPERAND; /* Get register number assuming address register. */ regno = (val & 7) + 8; @@ -1032,21 +1046,21 @@ print_insn_arg (const char *d, break; case 5: - NEXTWORD (p, val, -3); + NEXTWORD (p, val, PRINT_INSN_ARG_MEMORY_ERROR); (*info->fprintf_func) (info->stream, "%s@(%d)", regname, val); break; case 6: p = print_indexed (regno, p, addr, info); if (p == NULL) - return -3; + return PRINT_INSN_ARG_MEMORY_ERROR; break; case 7: switch (val & 7) { case 0: - NEXTWORD (p, val, -3); + NEXTWORD (p, val, PRINT_INSN_ARG_MEMORY_ERROR); (*info->print_address_func) (val, info); break; @@ -1056,7 +1070,7 @@ print_insn_arg (const char *d, break; case 2: - NEXTWORD (p, val, -3); + NEXTWORD (p, val, PRINT_INSN_ARG_MEMORY_ERROR); (*info->fprintf_func) (info->stream, "%%pc@("); (*info->print_address_func) (addr + val, info); (*info->fprintf_func) (info->stream, ")"); @@ -1065,7 +1079,7 @@ print_insn_arg (const char *d, case 3: p = print_indexed (-1, p, addr, info); if (p == NULL) - return -3; + return PRINT_INSN_ARG_MEMORY_ERROR; break; case 4: @@ -1078,12 +1092,12 @@ print_insn_arg (const char *d, break; case 'w': - NEXTWORD (p, val, -3); + NEXTWORD (p, val, PRINT_INSN_ARG_MEMORY_ERROR); flt_p = 0; break; case 'l': - NEXTLONG (p, val, -3); + NEXTLONG (p, val, PRINT_INSN_ARG_MEMORY_ERROR); flt_p = 0; break; @@ -1104,7 +1118,7 @@ print_insn_arg (const char *d, break; default: - return -1; + return PRINT_INSN_ARG_INVALID_OPERAND; } if (flt_p) /* Print a float? */ (*info->fprintf_func) (info->stream, "#0e%g", flval); @@ -1113,7 +1127,7 @@ print_insn_arg (const char *d, break; default: - return -1; + return PRINT_INSN_ARG_INVALID_OPERAND; } } @@ -1134,7 +1148,7 @@ print_insn_arg (const char *d, { char doneany; p1 = buffer + 2; - NEXTWORD (p1, val, -3); + NEXTWORD (p1, val, PRINT_INSN_ARG_MEMORY_ERROR); /* Move the pointer ahead if this point is farther ahead than the last. */ p = p1 > p ? p1 : p; @@ -1215,7 +1229,7 @@ print_insn_arg (const char *d, (*info->fprintf_func) (info->stream, "%s", fpcr_names[val]); } else - return -2; + return PRINT_INSN_ARG_INVALID_OP_TABLE; break; case 'X': @@ -1310,7 +1324,7 @@ print_insn_arg (const char *d, break; default: - return -2; + return PRINT_INSN_ARG_INVALID_OP_TABLE; } return p - p0; @@ -1420,7 +1434,8 @@ match_insn_m68k (bfd_vma memaddr, if (eaten >= 0) p += eaten; - else if (eaten == -1 || eaten == -3) + else if (eaten == PRINT_INSN_ARG_INVALID_OPERAND + || eaten == PRINT_INSN_ARG_MEMORY_ERROR) { info->fprintf_func = save_printer; info->print_address_func = save_print_address; -- 2.7.4