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author | Maciej W. Rozycki <macro@linux-mips.org> | 2012-03-01 22:37:51 +0000 |
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committer | Maciej W. Rozycki <macro@linux-mips.org> | 2012-03-01 22:37:51 +0000 |
commit | a385295e2c80123b85dab47754e049e418925484 (patch) | |
tree | c21e950769ad0845c2fdbb1990a1f6783685a6fe /gdb/mips-tdep.c | |
parent | 1faeff088bbbd037d7769d214378b4faf805fa2e (diff) | |
download | gdb-a385295e2c80123b85dab47754e049e418925484.zip gdb-a385295e2c80123b85dab47754e049e418925484.tar.gz gdb-a385295e2c80123b85dab47754e049e418925484.tar.bz2 |
* mips-tdep.c (mips32_bc1_pc): New function.
(mips32_next_pc): Handle BC1ANY2F, BC1ANY2T, BC1ANY4F, BC1ANY4T,
BPOSGE32 and BPOSGE64 instructions.
(deal_with_atomic_sequence): Likewise.
(mips32_instruction_has_delay_slot): Likewise.
Diffstat (limited to 'gdb/mips-tdep.c')
-rw-r--r-- | gdb/mips-tdep.c | 105 |
1 files changed, 85 insertions, 20 deletions
diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c index 3e09d5c..bf396f9 100644 --- a/gdb/mips-tdep.c +++ b/gdb/mips-tdep.c @@ -1132,6 +1132,36 @@ mips32_relative_offset (ULONGEST inst) return ((itype_immediate (inst) ^ 0x8000) - 0x8000) << 2; } +/* Determine the address of the next instruction executed after the INST + floating condition branch instruction at PC. COUNT specifies the + number of the floating condition bits tested by the branch. */ + +static CORE_ADDR +mips32_bc1_pc (struct gdbarch *gdbarch, struct frame_info *frame, + ULONGEST inst, CORE_ADDR pc, int count) +{ + int fcsr = mips_regnum (gdbarch)->fp_control_status; + int cnum = (itype_rt (inst) >> 2) & (count - 1); + int tf = itype_rt (inst) & 1; + int mask = (1 << count) - 1; + ULONGEST fcs; + int cond; + + if (fcsr == -1) + /* No way to handle; it'll most likely trap anyway. */ + return pc; + + fcs = get_frame_register_unsigned (frame, fcsr); + cond = ((fcs >> 24) & 0xfe) | ((fcs >> 23) & 0x01); + + if (((cond >> cnum) & mask) != mask * !tf) + pc += mips32_relative_offset (inst); + else + pc += 4; + + return pc; +} + /* Determine where to set a single step breakpoint while considering branch prediction. */ static CORE_ADDR @@ -1164,20 +1194,15 @@ mips32_next_pc (struct frame_info *frame, CORE_ADDR pc) } else if (itype_op (inst) == 17 && itype_rs (inst) == 8) /* BC1F, BC1FL, BC1T, BC1TL: 010001 01000 */ - { - int tf = itype_rt (inst) & 0x01; - int cnum = itype_rt (inst) >> 2; - int fcrcs = - get_frame_register_signed (frame, - mips_regnum (get_frame_arch (frame))-> - fp_control_status); - int cond = ((fcrcs >> 24) & 0xfe) | ((fcrcs >> 23) & 0x01); - - if (((cond >> cnum) & 0x01) == tf) - pc += mips32_relative_offset (inst) + 4; - else - pc += 8; - } + pc = mips32_bc1_pc (gdbarch, frame, inst, pc + 4, 1); + else if (itype_op (inst) == 17 && itype_rs (inst) == 9 + && (itype_rt (inst) & 2) == 0) + /* BC1ANY2F, BC1ANY2T: 010001 01001 xxx0x */ + pc = mips32_bc1_pc (gdbarch, frame, inst, pc + 4, 2); + else if (itype_op (inst) == 17 && itype_rs (inst) == 10 + && (itype_rt (inst) & 2) == 0) + /* BC1ANY4F, BC1ANY4T: 010001 01010 xxx0x */ + pc = mips32_bc1_pc (gdbarch, frame, inst, pc + 4, 4); else pc += 4; /* Not a branch, next instruction is easy. */ } @@ -1236,6 +1261,25 @@ mips32_next_pc (struct frame_info *frame, CORE_ADDR pc) else pc += 8; /* after the delay slot */ break; + case 0x1c: /* BPOSGE32 */ + case 0x1e: /* BPOSGE64 */ + pc += 4; + if (itype_rs (inst) == 0) + { + unsigned int pos = (op & 2) ? 64 : 32; + int dspctl = mips_regnum (gdbarch)->dspctl; + + if (dspctl == -1) + /* No way to handle; it'll most likely trap anyway. */ + break; + + if ((get_frame_register_unsigned (frame, + dspctl) & 0x7f) >= pos) + pc += mips32_relative_offset (inst); + else + pc += 4; + } + break; /* All of the other instructions in the REGIMM category */ default: pc += 4; @@ -2618,7 +2662,9 @@ deal_with_atomic_sequence (struct gdbarch *gdbarch, return 0; /* fallback to the standard single-step code. */ break; case 1: /* REGIMM */ - is_branch = ((itype_rt (insn) & 0xc) == 0); /* B{LT,GE}Z* */ + is_branch = ((itype_rt (insn) & 0xc) == 0 /* B{LT,GE}Z* */ + || ((itype_rt (insn) & 0x1e) == 0 + && itype_rs (insn) == 0)); /* BPOSGE* */ break; case 2: /* J */ case 3: /* JAL */ @@ -2634,6 +2680,11 @@ deal_with_atomic_sequence (struct gdbarch *gdbarch, is_branch = 1; break; case 17: /* COP1 */ + is_branch = ((itype_rs (insn) == 9 || itype_rs (insn) == 10) + && (itype_rt (insn) & 0x2) == 0); + if (is_branch) /* BC1ANY2F, BC1ANY2T, BC1ANY4F, BC1ANY4T */ + break; + /* Fall through. */ case 18: /* COP2 */ case 19: /* COP3 */ is_branch = (itype_rs (insn) == 8); /* BCzF, BCzFL, BCzT, BCzTL */ @@ -5333,6 +5384,8 @@ mips32_instruction_has_delay_slot (struct gdbarch *gdbarch, CORE_ADDR addr) unsigned long inst; int status; int op; + int rs; + int rt; status = target_read_memory (addr, buf, MIPS_INSN32_SIZE); if (status) @@ -5341,10 +5394,19 @@ mips32_instruction_has_delay_slot (struct gdbarch *gdbarch, CORE_ADDR addr) inst = mips_fetch_instruction (gdbarch, addr); op = itype_op (inst); if ((inst & 0xe0000000) != 0) - return (op >> 2 == 5 /* BEQL, BNEL, BLEZL, BGTZL: bits 0101xx */ - || op == 29 /* JALX: bits 011101 */ - || (op == 17 && itype_rs (inst) == 8)); + { + rs = itype_rs (inst); + rt = itype_rt (inst); + return (op >> 2 == 5 /* BEQL, BNEL, BLEZL, BGTZL: bits 0101xx */ + || op == 29 /* JALX: bits 011101 */ + || (op == 17 + && (rs == 8 /* BC1F, BC1FL, BC1T, BC1TL: 010001 01000 */ + || (rs == 9 && (rt & 0x2) == 0) + /* BC1ANY2F, BC1ANY2T: bits 010001 01001 */ + || (rs == 10 && (rt & 0x2) == 0)))); + /* BC1ANY4F, BC1ANY4T: bits 010001 01010 */ + } else switch (op & 0x07) /* extract bits 28,27,26 */ { @@ -5354,10 +5416,13 @@ mips32_instruction_has_delay_slot (struct gdbarch *gdbarch, CORE_ADDR addr) || op == 9); /* JALR */ break; /* end SPECIAL */ case 1: /* REGIMM */ - op = itype_rt (inst); /* branch condition */ - return (op & 0xc) == 0; + rs = itype_rs (inst); + rt = itype_rt (inst); /* branch condition */ + return ((rt & 0xc) == 0 /* BLTZ, BLTZL, BGEZ, BGEZL: bits 000xx */ /* BLTZAL, BLTZALL, BGEZAL, BGEZALL: 100xx */ + || ((rt & 0x1e) == 0x1c && rs == 0)); + /* BPOSGE32, BPOSGE64: bits 1110x */ break; /* end REGIMM */ default: /* J, JAL, BEQ, BNE, BLEZ, BGTZ */ return 1; |