X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Faarch64-linux-tdep.c;h=b854dcdd58cb357981ca8b226e85429c209f8642;hb=aa1f7fb133a5a4f95af8286f58b689d6ae131488;hp=93b6d416a3e43300c1eaa2e1e807b60160e232c9;hpb=00431a78b28f913a9d5c912c49680e39cfd20847;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/aarch64-linux-tdep.c b/gdb/aarch64-linux-tdep.c index 93b6d416a3..b854dcdd58 100644 --- a/gdb/aarch64-linux-tdep.c +++ b/gdb/aarch64-linux-tdep.c @@ -1,6 +1,6 @@ /* Target-dependent code for GNU/Linux AArch64. - Copyright (C) 2009-2018 Free Software Foundation, Inc. + Copyright (C) 2009-2020 Free Software Foundation, Inc. Contributed by ARM Ltd. This file is part of GDB. @@ -21,7 +21,6 @@ #include "defs.h" #include "gdbarch.h" -#include "arch-utils.h" #include "glibc-tdep.h" #include "linux-tdep.h" #include "aarch64-tdep.h" @@ -31,12 +30,11 @@ #include "symtab.h" #include "tramp-frame.h" #include "trad-frame.h" +#include "target/target.h" -#include "inferior.h" #include "regcache.h" #include "regset.h" -#include "cli/cli-utils.h" #include "stap-probe.h" #include "parser-defs.h" #include "user-regs.h" @@ -45,8 +43,6 @@ #include "record-full.h" #include "linux-record.h" -#include "auxv.h" -#include "elf/common.h" /* Signal frame handling. @@ -85,11 +81,6 @@ struct ucontext uc; }; - typedef struct - { - ... 128 bytes - } siginfo_t; - The ucontext has the following form: struct ucontext { @@ -100,13 +91,6 @@ struct sigcontext uc_mcontext; }; - typedef struct sigaltstack - { - void *ss_sp; - int ss_flags; - size_t ss_size; - } stack_t; - struct sigcontext { unsigned long fault_address; @@ -117,6 +101,17 @@ __u8 __reserved[4096] }; + The reserved space in sigcontext contains additional structures, each starting + with a aarch64_ctx, which specifies a unique identifier and the total size of + the structure. The final structure in reserved will start will a null + aarch64_ctx. The penultimate entry in reserved may be a extra_context which + then points to a further block of reserved space. + + struct aarch64_ctx { + u32 magic; + u32 size; + }; + The restorer stub will always have the form: d28015a8 movz x8, #0xad @@ -136,6 +131,54 @@ #define AARCH64_RT_SIGFRAME_UCONTEXT_OFFSET 128 #define AARCH64_UCONTEXT_SIGCONTEXT_OFFSET 176 #define AARCH64_SIGCONTEXT_XO_OFFSET 8 +#define AARCH64_SIGCONTEXT_RESERVED_OFFSET 288 + +#define AARCH64_SIGCONTEXT_RESERVED_SIZE 4096 + +/* Unique identifiers that may be used for aarch64_ctx.magic. */ +#define AARCH64_EXTRA_MAGIC 0x45585401 +#define AARCH64_FPSIMD_MAGIC 0x46508001 +#define AARCH64_SVE_MAGIC 0x53564501 + +/* Defines for the extra_context that follows an AARCH64_EXTRA_MAGIC. */ +#define AARCH64_EXTRA_DATAP_OFFSET 8 + +/* Defines for the fpsimd that follows an AARCH64_FPSIMD_MAGIC. */ +#define AARCH64_FPSIMD_FPSR_OFFSET 8 +#define AARCH64_FPSIMD_FPCR_OFFSET 12 +#define AARCH64_FPSIMD_V0_OFFSET 16 +#define AARCH64_FPSIMD_VREG_SIZE 16 + +/* Defines for the sve structure that follows an AARCH64_SVE_MAGIC. */ +#define AARCH64_SVE_CONTEXT_VL_OFFSET 8 +#define AARCH64_SVE_CONTEXT_REGS_OFFSET 16 +#define AARCH64_SVE_CONTEXT_P_REGS_OFFSET(vq) (32 * vq * 16) +#define AARCH64_SVE_CONTEXT_FFR_OFFSET(vq) \ + (AARCH64_SVE_CONTEXT_P_REGS_OFFSET (vq) + (16 * vq * 2)) +#define AARCH64_SVE_CONTEXT_SIZE(vq) \ + (AARCH64_SVE_CONTEXT_FFR_OFFSET (vq) + (vq * 2)) + + +/* Read an aarch64_ctx, returning the magic value, and setting *SIZE to the + size, or return 0 on error. */ + +static uint32_t +read_aarch64_ctx (CORE_ADDR ctx_addr, enum bfd_endian byte_order, + uint32_t *size) +{ + uint32_t magic = 0; + gdb_byte buf[4]; + + if (target_read_memory (ctx_addr, buf, 4) != 0) + return 0; + magic = extract_unsigned_integer (buf, 4, byte_order); + + if (target_read_memory (ctx_addr + 4, buf, 4) != 0) + return 0; + *size = extract_unsigned_integer (buf, 4, byte_order); + + return magic; +} /* Implement the "init" method of struct tramp_frame. */ @@ -145,19 +188,28 @@ aarch64_linux_sigframe_init (const struct tramp_frame *self, struct trad_frame_cache *this_cache, CORE_ADDR func) { + struct gdbarch *gdbarch = get_frame_arch (this_frame); + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); CORE_ADDR sp = get_frame_register_unsigned (this_frame, AARCH64_SP_REGNUM); - CORE_ADDR sigcontext_addr = - sp - + AARCH64_RT_SIGFRAME_UCONTEXT_OFFSET - + AARCH64_UCONTEXT_SIGCONTEXT_OFFSET; - int i; - - for (i = 0; i < 31; i++) + CORE_ADDR sigcontext_addr = (sp + AARCH64_RT_SIGFRAME_UCONTEXT_OFFSET + + AARCH64_UCONTEXT_SIGCONTEXT_OFFSET ); + CORE_ADDR section = sigcontext_addr + AARCH64_SIGCONTEXT_RESERVED_OFFSET; + CORE_ADDR section_end = section + AARCH64_SIGCONTEXT_RESERVED_SIZE; + CORE_ADDR fpsimd = 0; + CORE_ADDR sve_regs = 0; + uint32_t size, magic; + bool extra_found = false; + int num_regs = gdbarch_num_regs (gdbarch); + + /* Read in the integer registers. */ + + for (int i = 0; i < 31; i++) { trad_frame_set_reg_addr (this_cache, AARCH64_X0_REGNUM + i, sigcontext_addr + AARCH64_SIGCONTEXT_XO_OFFSET - + i * AARCH64_SIGCONTEXT_REG_SIZE); + + i * AARCH64_SIGCONTEXT_REG_SIZE); } trad_frame_set_reg_addr (this_cache, AARCH64_SP_REGNUM, sigcontext_addr + AARCH64_SIGCONTEXT_XO_OFFSET @@ -166,6 +218,143 @@ aarch64_linux_sigframe_init (const struct tramp_frame *self, sigcontext_addr + AARCH64_SIGCONTEXT_XO_OFFSET + 32 * AARCH64_SIGCONTEXT_REG_SIZE); + /* Search for the FP and SVE sections, stopping at null. */ + while ((magic = read_aarch64_ctx (section, byte_order, &size)) != 0 + && size != 0) + { + switch (magic) + { + case AARCH64_FPSIMD_MAGIC: + fpsimd = section; + section += size; + break; + + case AARCH64_SVE_MAGIC: + { + /* Check if the section is followed by a full SVE dump, and set + sve_regs if it is. */ + gdb_byte buf[4]; + uint16_t vq; + + if (!tdep->has_sve ()) + break; + + if (target_read_memory (section + AARCH64_SVE_CONTEXT_VL_OFFSET, + buf, 2) != 0) + { + section += size; + break; + } + vq = sve_vq_from_vl (extract_unsigned_integer (buf, 2, byte_order)); + + if (vq != tdep->vq) + error (_("Invalid vector length in signal frame %d vs %s."), vq, + pulongest (tdep->vq)); + + if (size >= AARCH64_SVE_CONTEXT_SIZE (vq)) + sve_regs = section + AARCH64_SVE_CONTEXT_REGS_OFFSET; + + section += size; + break; + } + + case AARCH64_EXTRA_MAGIC: + { + /* Extra is always the last valid section in reserved and points to + an additional block of memory filled with more sections. Reset + the address to the extra section and continue looking for more + structures. */ + gdb_byte buf[8]; + + if (target_read_memory (section + AARCH64_EXTRA_DATAP_OFFSET, + buf, 8) != 0) + { + section += size; + break; + } + + section = extract_unsigned_integer (buf, 8, byte_order); + extra_found = true; + break; + } + + default: + section += size; + break; + } + + /* Prevent searching past the end of the reserved section. The extra + section does not have a hard coded limit - we have to rely on it ending + with nulls. */ + if (!extra_found && section > section_end) + break; + } + + if (sve_regs != 0) + { + CORE_ADDR offset; + + for (int i = 0; i < 32; i++) + { + offset = sve_regs + (i * tdep->vq * 16); + trad_frame_set_reg_addr (this_cache, AARCH64_SVE_Z0_REGNUM + i, + offset); + trad_frame_set_reg_addr (this_cache, + num_regs + AARCH64_SVE_V0_REGNUM + i, + offset); + trad_frame_set_reg_addr (this_cache, num_regs + AARCH64_Q0_REGNUM + i, + offset); + trad_frame_set_reg_addr (this_cache, num_regs + AARCH64_D0_REGNUM + i, + offset); + trad_frame_set_reg_addr (this_cache, num_regs + AARCH64_S0_REGNUM + i, + offset); + trad_frame_set_reg_addr (this_cache, num_regs + AARCH64_H0_REGNUM + i, + offset); + trad_frame_set_reg_addr (this_cache, num_regs + AARCH64_B0_REGNUM + i, + offset); + } + + offset = sve_regs + AARCH64_SVE_CONTEXT_P_REGS_OFFSET (tdep->vq); + for (int i = 0; i < 16; i++) + trad_frame_set_reg_addr (this_cache, AARCH64_SVE_P0_REGNUM + i, + offset + (i * tdep->vq * 2)); + + offset = sve_regs + AARCH64_SVE_CONTEXT_FFR_OFFSET (tdep->vq); + trad_frame_set_reg_addr (this_cache, AARCH64_SVE_FFR_REGNUM, offset); + } + + if (fpsimd != 0) + { + trad_frame_set_reg_addr (this_cache, AARCH64_FPSR_REGNUM, + fpsimd + AARCH64_FPSIMD_FPSR_OFFSET); + trad_frame_set_reg_addr (this_cache, AARCH64_FPCR_REGNUM, + fpsimd + AARCH64_FPSIMD_FPCR_OFFSET); + + /* If there was no SVE section then set up the V registers. */ + if (sve_regs == 0) + for (int i = 0; i < 32; i++) + { + CORE_ADDR offset = (fpsimd + AARCH64_FPSIMD_V0_OFFSET + + (i * AARCH64_FPSIMD_VREG_SIZE)); + + trad_frame_set_reg_addr (this_cache, AARCH64_V0_REGNUM + i, offset); + trad_frame_set_reg_addr (this_cache, + num_regs + AARCH64_Q0_REGNUM + i, offset); + trad_frame_set_reg_addr (this_cache, + num_regs + AARCH64_D0_REGNUM + i, offset); + trad_frame_set_reg_addr (this_cache, + num_regs + AARCH64_S0_REGNUM + i, offset); + trad_frame_set_reg_addr (this_cache, + num_regs + AARCH64_H0_REGNUM + i, offset); + trad_frame_set_reg_addr (this_cache, + num_regs + AARCH64_B0_REGNUM + i, offset); + if (tdep->has_sve ()) + trad_frame_set_reg_addr (this_cache, + num_regs + AARCH64_SVE_V0_REGNUM + i, + offset); + } + } + trad_frame_set_id (this_cache, frame_id_build (sp, func)); } @@ -176,12 +365,12 @@ static const struct tramp_frame aarch64_linux_rt_sigframe = { /* movz x8, 0x8b (S=1,o=10,h=0,i=0x8b,r=8) Soo1 0010 1hhi iiii iiii iiii iiir rrrr */ - {0xd2801168, -1}, + {0xd2801168, ULONGEST_MAX}, /* svc 0x0 (o=0, l=1) 1101 0100 oooi iiii iiii iiii iii0 00ll */ - {0xd4000001, -1}, - {TRAMP_SENTINEL_INSN, -1} + {0xd4000001, ULONGEST_MAX}, + {TRAMP_SENTINEL_INSN, ULONGEST_MAX} }, aarch64_linux_sigframe_init }; @@ -219,6 +408,180 @@ const struct regset aarch64_linux_fpregset = regcache_supply_regset, regcache_collect_regset }; +/* The fields in an SVE header at the start of a SVE regset. */ + +#define SVE_HEADER_SIZE_LENGTH 4 +#define SVE_HEADER_MAX_SIZE_LENGTH 4 +#define SVE_HEADER_VL_LENGTH 2 +#define SVE_HEADER_MAX_VL_LENGTH 2 +#define SVE_HEADER_FLAGS_LENGTH 2 +#define SVE_HEADER_RESERVED_LENGTH 2 + +#define SVE_HEADER_SIZE_OFFSET 0 +#define SVE_HEADER_MAX_SIZE_OFFSET \ + (SVE_HEADER_SIZE_OFFSET + SVE_HEADER_SIZE_LENGTH) +#define SVE_HEADER_VL_OFFSET \ + (SVE_HEADER_MAX_SIZE_OFFSET + SVE_HEADER_MAX_SIZE_LENGTH) +#define SVE_HEADER_MAX_VL_OFFSET \ + (SVE_HEADER_VL_OFFSET + SVE_HEADER_VL_LENGTH) +#define SVE_HEADER_FLAGS_OFFSET \ + (SVE_HEADER_MAX_VL_OFFSET + SVE_HEADER_MAX_VL_LENGTH) +#define SVE_HEADER_RESERVED_OFFSET \ + (SVE_HEADER_FLAGS_OFFSET + SVE_HEADER_FLAGS_LENGTH) +#define SVE_HEADER_SIZE \ + (SVE_HEADER_RESERVED_OFFSET + SVE_HEADER_RESERVED_LENGTH) + +#define SVE_HEADER_FLAG_SVE 1 + +/* Get VQ value from SVE section in the core dump. */ + +static uint64_t +aarch64_linux_core_read_vq (struct gdbarch *gdbarch, bfd *abfd) +{ + gdb_byte header[SVE_HEADER_SIZE]; + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); + asection *sve_section = bfd_get_section_by_name (abfd, ".reg-aarch-sve"); + + if (sve_section == nullptr) + { + /* No SVE state. */ + return 0; + } + + size_t size = bfd_section_size (sve_section); + + /* Check extended state size. */ + if (size < SVE_HEADER_SIZE) + { + warning (_("'.reg-aarch-sve' section in core file too small.")); + return 0; + } + + if (!bfd_get_section_contents (abfd, sve_section, header, 0, SVE_HEADER_SIZE)) + { + warning (_("Couldn't read sve header from " + "'.reg-aarch-sve' section in core file.")); + return 0; + } + + uint64_t vl = extract_unsigned_integer (header + SVE_HEADER_VL_OFFSET, + SVE_HEADER_VL_LENGTH, byte_order); + uint64_t vq = sve_vq_from_vl (vl); + + if (vq > AARCH64_MAX_SVE_VQ) + { + warning (_("SVE Vector length in core file not supported by this version" + " of GDB. (VQ=%s)"), pulongest (vq)); + return 0; + } + else if (vq == 0) + { + warning (_("SVE Vector length in core file is invalid. (VQ=%s"), + pulongest (vq)); + return 0; + } + + return vq; +} + +/* Supply register REGNUM from BUF to REGCACHE, using the register map + in REGSET. If REGNUM is -1, do this for all registers in REGSET. + If BUF is NULL, set the registers to "unavailable" status. */ + +static void +aarch64_linux_supply_sve_regset (const struct regset *regset, + struct regcache *regcache, + int regnum, const void *buf, size_t size) +{ + gdb_byte *header = (gdb_byte *) buf; + struct gdbarch *gdbarch = regcache->arch (); + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); + + if (buf == nullptr) + return regcache->supply_regset (regset, regnum, nullptr, size); + gdb_assert (size > SVE_HEADER_SIZE); + + /* BUF contains an SVE header followed by a register dump of either the + passed in SVE regset or a NEON fpregset. */ + + /* Extract required fields from the header. */ + ULONGEST vl = extract_unsigned_integer (header + SVE_HEADER_VL_OFFSET, + SVE_HEADER_VL_LENGTH, byte_order); + uint16_t flags = extract_unsigned_integer (header + SVE_HEADER_FLAGS_OFFSET, + SVE_HEADER_FLAGS_LENGTH, + byte_order); + + if (regnum == -1 || regnum == AARCH64_SVE_VG_REGNUM) + { + gdb_byte vg_target[8]; + store_integer ((gdb_byte *)&vg_target, sizeof (uint64_t), byte_order, + sve_vg_from_vl (vl)); + regcache->raw_supply (AARCH64_SVE_VG_REGNUM, &vg_target); + } + + if (flags & SVE_HEADER_FLAG_SVE) + { + /* Register dump is a SVE structure. */ + regcache->supply_regset (regset, regnum, + (gdb_byte *) buf + SVE_HEADER_SIZE, + size - SVE_HEADER_SIZE); + } + else + { + /* Register dump is a fpsimd structure. First clear the SVE + registers. */ + for (int i = 0; i < AARCH64_SVE_Z_REGS_NUM; i++) + regcache->raw_supply_zeroed (AARCH64_SVE_Z0_REGNUM + i); + for (int i = 0; i < AARCH64_SVE_P_REGS_NUM; i++) + regcache->raw_supply_zeroed (AARCH64_SVE_P0_REGNUM + i); + regcache->raw_supply_zeroed (AARCH64_SVE_FFR_REGNUM); + + /* Then supply the fpsimd registers. */ + regcache->supply_regset (&aarch64_linux_fpregset, regnum, + (gdb_byte *) buf + SVE_HEADER_SIZE, + size - SVE_HEADER_SIZE); + } +} + +/* Collect register REGNUM from REGCACHE to BUF, using the register + map in REGSET. If REGNUM is -1, do this for all registers in + REGSET. */ + +static void +aarch64_linux_collect_sve_regset (const struct regset *regset, + const struct regcache *regcache, + int regnum, void *buf, size_t size) +{ + gdb_byte *header = (gdb_byte *) buf; + struct gdbarch *gdbarch = regcache->arch (); + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); + uint64_t vq = gdbarch_tdep (gdbarch)->vq; + + gdb_assert (buf != NULL); + gdb_assert (size > SVE_HEADER_SIZE); + + /* BUF starts with a SVE header prior to the register dump. */ + + store_unsigned_integer (header + SVE_HEADER_SIZE_OFFSET, + SVE_HEADER_SIZE_LENGTH, byte_order, size); + store_unsigned_integer (header + SVE_HEADER_MAX_SIZE_OFFSET, + SVE_HEADER_MAX_SIZE_LENGTH, byte_order, size); + store_unsigned_integer (header + SVE_HEADER_VL_OFFSET, SVE_HEADER_VL_LENGTH, + byte_order, sve_vl_from_vq (vq)); + store_unsigned_integer (header + SVE_HEADER_MAX_VL_OFFSET, + SVE_HEADER_MAX_VL_LENGTH, byte_order, + sve_vl_from_vq (vq)); + store_unsigned_integer (header + SVE_HEADER_FLAGS_OFFSET, + SVE_HEADER_FLAGS_LENGTH, byte_order, + SVE_HEADER_FLAG_SVE); + store_unsigned_integer (header + SVE_HEADER_RESERVED_OFFSET, + SVE_HEADER_RESERVED_LENGTH, byte_order, 0); + + /* The SVE register dump follows. */ + regcache->collect_regset (regset, regnum, (gdb_byte *) buf + SVE_HEADER_SIZE, + size - SVE_HEADER_SIZE); +} + /* Implement the "regset_from_core_section" gdbarch method. */ static void @@ -227,25 +590,71 @@ aarch64_linux_iterate_over_regset_sections (struct gdbarch *gdbarch, void *cb_data, const struct regcache *regcache) { - cb (".reg", AARCH64_LINUX_SIZEOF_GREGSET, &aarch64_linux_gregset, - NULL, cb_data); - cb (".reg2", AARCH64_LINUX_SIZEOF_FPREGSET, &aarch64_linux_fpregset, - NULL, cb_data); + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); + + cb (".reg", AARCH64_LINUX_SIZEOF_GREGSET, AARCH64_LINUX_SIZEOF_GREGSET, + &aarch64_linux_gregset, NULL, cb_data); + + if (tdep->has_sve ()) + { + /* Create this on the fly in order to handle vector register sizes. */ + const struct regcache_map_entry sve_regmap[] = + { + { 32, AARCH64_SVE_Z0_REGNUM, (int) (tdep->vq * 16) }, + { 16, AARCH64_SVE_P0_REGNUM, (int) (tdep->vq * 16 / 8) }, + { 1, AARCH64_SVE_FFR_REGNUM, 4 }, + { 1, AARCH64_FPSR_REGNUM, 4 }, + { 1, AARCH64_FPCR_REGNUM, 4 }, + { 0 } + }; + + const struct regset aarch64_linux_sve_regset = + { + sve_regmap, + aarch64_linux_supply_sve_regset, aarch64_linux_collect_sve_regset, + REGSET_VARIABLE_SIZE + }; + + cb (".reg-aarch-sve", + SVE_HEADER_SIZE + regcache_map_entry_size (aarch64_linux_fpregmap), + SVE_HEADER_SIZE + regcache_map_entry_size (sve_regmap), + &aarch64_linux_sve_regset, "SVE registers", cb_data); + } + else + cb (".reg2", AARCH64_LINUX_SIZEOF_FPREGSET, AARCH64_LINUX_SIZEOF_FPREGSET, + &aarch64_linux_fpregset, NULL, cb_data); + + + if (tdep->has_pauth ()) + { + /* Create this on the fly in order to handle the variable location. */ + const struct regcache_map_entry pauth_regmap[] = + { + { 2, AARCH64_PAUTH_DMASK_REGNUM (tdep->pauth_reg_base), 8}, + { 0 } + }; + + const struct regset aarch64_linux_pauth_regset = + { + pauth_regmap, regcache_supply_regset, regcache_collect_regset + }; + + cb (".reg-aarch-pauth", AARCH64_LINUX_SIZEOF_PAUTH, + AARCH64_LINUX_SIZEOF_PAUTH, &aarch64_linux_pauth_regset, + "pauth registers", cb_data); + } } -/* Implement the "core_read_description" gdbarch method. SVE not yet - supported. */ +/* Implement the "core_read_description" gdbarch method. */ static const struct target_desc * aarch64_linux_core_read_description (struct gdbarch *gdbarch, struct target_ops *target, bfd *abfd) { - CORE_ADDR aarch64_hwcap = 0; + CORE_ADDR hwcap = linux_get_hwcap (target); - if (target_auxv_search (target, AT_HWCAP, &aarch64_hwcap) != 1) - return NULL; - - return aarch64_read_description (0); + return aarch64_read_description (aarch64_linux_core_read_vq (gdbarch, abfd), + hwcap & AARCH64_HWCAP_PACA); } /* Implementation of `gdbarch_stap_is_single_operand', as defined in @@ -362,28 +771,6 @@ aarch64_stap_parse_special_token (struct gdbarch *gdbarch, return 1; } -/* Implement the "get_syscall_number" gdbarch method. */ - -static LONGEST -aarch64_linux_get_syscall_number (struct gdbarch *gdbarch, - thread_info *thread) -{ - struct regcache *regs = get_thread_regcache (thread); - enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); - - /* The content of register x8. */ - gdb_byte buf[X_REGISTER_SIZE]; - /* The result. */ - LONGEST ret; - - /* Getting the system call number from the register x8. */ - regs->cooked_read (AARCH64_DWARF_X0 + 8, buf); - - ret = extract_signed_integer (buf, X_REGISTER_SIZE, byte_order); - - return ret; -} - /* AArch64 process record-replay constructs: syscall, signal etc. */ struct linux_record_tdep aarch64_linux_record_tdep; @@ -939,6 +1326,40 @@ aarch64_canonicalize_syscall (enum aarch64_syscall syscall_number) } } +/* Retrieve the syscall number at a ptrace syscall-stop, either on syscall entry + or exit. Return -1 upon error. */ + +static LONGEST +aarch64_linux_get_syscall_number (struct gdbarch *gdbarch, thread_info *thread) +{ + struct regcache *regs = get_thread_regcache (thread); + LONGEST ret; + + /* Get the system call number from register x8. */ + regs->cooked_read (AARCH64_X0_REGNUM + 8, &ret); + + /* On exit from a successful execve, we will be in a new process and all the + registers will be cleared - x0 to x30 will be 0, except for a 1 in x7. + This function will only ever get called when stopped at the entry or exit + of a syscall, so by checking for 0 in x0 (arg0/retval), x1 (arg1), x8 + (syscall), x29 (FP) and x30 (LR) we can infer: + 1) Either inferior is at exit from successful execve. + 2) Or inferior is at entry to a call to io_setup with invalid arguments and + a corrupted FP and LR. + It should be safe enough to assume case 1. */ + if (ret == 0) + { + LONGEST x1 = -1, fp = -1, lr = -1; + regs->cooked_read (AARCH64_X0_REGNUM + 1, &x1); + regs->cooked_read (AARCH64_FP_REGNUM, &fp); + regs->cooked_read (AARCH64_LR_REGNUM, &lr); + if (x1 == 0 && fp ==0 && lr == 0) + return aarch64_sys_execve; + } + + return ret; +} + /* Record all registers but PC register for process-record. */ static int @@ -1004,11 +1425,11 @@ aarch64_linux_syscall_record (struct regcache *regcache, /* Implement the "gcc_target_options" gdbarch method. */ -static char * +static std::string aarch64_linux_gcc_target_options (struct gdbarch *gdbarch) { /* GCC doesn't know "-m64". */ - return NULL; + return {}; } static void @@ -1233,7 +1654,7 @@ aarch64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) set_gdbarch_get_syscall_number (gdbarch, aarch64_linux_get_syscall_number); /* Displaced stepping. */ - set_gdbarch_max_insn_length (gdbarch, 4 * DISPLACED_MODIFIED_INSNS); + set_gdbarch_max_insn_length (gdbarch, 4 * AARCH64_DISPLACED_MODIFIED_INSNS); set_gdbarch_displaced_step_copy_insn (gdbarch, aarch64_displaced_step_copy_insn); set_gdbarch_displaced_step_fixup (gdbarch, aarch64_displaced_step_fixup);