From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25307 invoked by alias); 21 Feb 2002 02:09:34 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 25026 invoked from network); 21 Feb 2002 02:09:30 -0000 Received: from unknown (HELO cygnus.com) (205.180.230.5) by sources.redhat.com with SMTP; 21 Feb 2002 02:09:30 -0000 Received: from localhost.redhat.com (cse.cygnus.com [205.180.230.236]) by runyon.cygnus.com (8.8.7-cygnus/8.8.7) with ESMTP id SAA22403; Wed, 20 Feb 2002 18:09:18 -0800 (PST) Received: by localhost.redhat.com (Postfix, from userid 469) id 78CF511403; Wed, 20 Feb 2002 21:09:08 -0500 (EST) From: Elena Zannoni MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15476.22212.358982.6179@localhost.redhat.com> Date: Wed, 20 Feb 2002 18:09:00 -0000 To: Daniel Jacobowitz Cc: Elena Zannoni , gdb-patches@sources.redhat.com Subject: Re: [RFA] ppc-linux-nat.c AltiVec regs ptrace In-Reply-To: <20020220193446.A9812@nevyn.them.org> References: <15476.1308.919907.110811@localhost.redhat.com> <20020220153946.A24439@nevyn.them.org> <15476.4080.303671.894065@localhost.redhat.com> <20020220171519.A28726@nevyn.them.org> <15476.11279.326712.932158@localhost.redhat.com> <20020220184649.B7963@nevyn.them.org> <15476.16171.455269.862123@localhost.redhat.com> <20020220193446.A9812@nevyn.them.org> X-Mailer: VM 7.00 under Emacs 20.7.1 X-SW-Source: 2002-02/txt/msg00581.txt.bz2 Daniel Jacobowitz writes: > On Wed, Feb 20, 2002 at 07:28:27PM -0500, Elena Zannoni wrote: > > In case of 2.2.5 the powerpc version of the file gets installed. While > > for 2.2.1 the one with the definitions for PTRACE_GETFPXREGS is installed. > > > > Ok then, should we support the older version or not? > > If not we have two options: > > > > 1. if glibc gets a patch with the new PTRACE_GETVRREGS requests, then > > we can add another different configuration check. > > > > 2. We can just rely on the run time check. Which means I have to redo > > the patch again [where is that bucket]. > > > > Actually doing just 2 would work also with the older version, I guess. > > Unless I am missing some other subtlety. Ok I'll change it. > > Sounds good to me. Might want to submit a patch to add GETVRREGS to > libc, also, I suppose... Yes, it's probably better. Here is a new patch. 2002-02-20 Elena Zannoni * ppc-linux-nat.c (PTRACE_GETVRREGS, PTRACE_SETVRREGS): Define. (have_ptrace_getvrregs): Define for run time checks. (fetch_register, store_register): Fetch/store altivec register when needed. (fetch_altivec_register, store_altivec-register): New functions. (supply_vrregset, fill_vrregset): New functions. (fetch_altivec_registers, store_altivec_registers): New functions. (fetch_ppc_registers, store_ppc_registers): Fetch/store altivec registers as well. Index: ppc-linux-nat.c =================================================================== RCS file: /cvs/uberbaum/gdb/ppc-linux-nat.c,v retrieving revision 1.15 diff -u -p -r1.15 ppc-linux-nat.c --- ppc-linux-nat.c 2002/02/18 15:08:40 1.15 +++ ppc-linux-nat.c 2002/02/21 02:06:49 @@ -51,6 +51,31 @@ #define PTRACE_XFER_TYPE int #endif +/* Glibc's headers don't define PTRACE_GETVRREGS so we cannot use a + configure time check. Some older glibc's (for instance 2.2.1) + don't have a specific powerpc version of ptrace.h, and fall back on + a generic one. In such cases, sys/ptrace.h defines + PTRACE_GETFPXREGS and PTRACE_SETFPXREGS to the same numbers that + ppc kernel's asm/ptrace.h defines PTRACE_GETVRREGS and + PTRACE_SETVRREGS to be. This also makes a configury check pretty + much useless. */ + +/* These definitions should really come from the glibc header files, + but Glibc doesn't know about the vrregs yet. */ +#define PTRACE_GETVRREGS 18 +#define PTRACE_SETVRREGS 19 + +/* This oddity is because the linux kernel defines elf_vrregset_t as + an array of 33 16 bytes long elements. I.e. it leaves out vrsave. + However the PTRACE_GETVRREGS and PTRACE_SETVRREGS requests return + the vrsave as an extra 4 bytes at the end. I opted for creating a + flat array of chars, so that it is easier to manipulate for gdb. */ +#define SIZEOF_VRREGS 33*16+4 +typedef char gdb_vrregset_t[SIZEOF_VRREGS]; + +/* For runtime check of ptrace support for VRREGS. */ +int have_ptrace_getvrregs = 1; + int kernel_u_size (void) { @@ -109,6 +134,40 @@ ppc_ptrace_cannot_fetch_store_register ( return (ppc_register_u_addr (regno) == -1); } +/* The linux kernel ptrace interface for AltiVec registers uses the + registers set mechanism, as opposed to the interface for all the + other registers, that stores/fetches each register individually. */ +static void +fetch_altivec_register (int tid, int regno) +{ + int ret; + int offset = 0; + gdb_vrregset_t regs; + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + int vrregsize = REGISTER_RAW_SIZE (tdep->ppc_vr0_regnum); + + ret = ptrace (PTRACE_GETVRREGS, tid, 0, ®s); + if (ret < 0) + { + if (errno == EIO) + { + have_ptrace_getvrregs = 0; + return; + } + perror_with_name ("Unable to fetch AltiVec register"); + } + + /* VSCR is fetched as a 16 bytes quantity, but it is really 4 bytes + long on the hardware. We deal only with the lower 4 bytes of the + vector. VRSAVE is at the end of the array in a 4 bytes slot, so + there is no need to define an offset for it. */ + if (regno == (tdep->ppc_vrsave_regnum - 1)) + offset = vrregsize - REGISTER_RAW_SIZE (tdep->ppc_vrsave_regnum); + + supply_register (regno, + regs + (regno - tdep->ppc_vr0_regnum) * vrregsize + offset); +} + static void fetch_register (int tid, int regno) { @@ -119,6 +178,22 @@ fetch_register (int tid, int regno) char *buf = alloca (MAX_REGISTER_RAW_SIZE); CORE_ADDR regaddr = ppc_register_u_addr (regno); + if (altivec_register_p (regno)) + { + /* If this is the first time through, or if it is not the first + time throuhg, and we have comfirmed that there is kernel + support for such a ptrace request, then go and fetch the + register. */ + if (have_ptrace_getvrregs) + { + fetch_altivec_register (tid, regno); + return; + } + /* If we have discovered that there is no ptrace support for + AltiVec registers, fall through and return zeroes, because + regaddr will be -1 in this case. */ + } + if (regaddr == -1) { memset (buf, '\0', REGISTER_RAW_SIZE (regno)); /* Supply zeroes */ @@ -142,14 +217,59 @@ fetch_register (int tid, int regno) supply_register (regno, buf); } +static void +supply_vrregset (gdb_vrregset_t *vrregsetp) +{ + int i; + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + int num_of_vrregs = tdep->ppc_vrsave_regnum - tdep->ppc_vr0_regnum; + int vrregsize = REGISTER_RAW_SIZE (tdep->ppc_vr0_regnum); + int offset = vrregsize - REGISTER_RAW_SIZE (tdep->ppc_vrsave_regnum); + + for (i = 0; i < num_of_vrregs - 1; i++) + { + /* The last 2 registers of this set are only 32 bit long, not + 128. However an offset is necessary only for VSCR because it + occupies a whole vector, while VRSAVE occupies a full 4 bytes + slot. */ + if (i == (tdep->ppc_vrsave_regnum - 1)) + supply_register (tdep->ppc_vr0_regnum + i, + *vrregsetp + i * vrregsize + offset); + else + supply_register (tdep->ppc_vr0_regnum + i, *vrregsetp + i * vrregsize); + } +} + +static void +fetch_altivec_registers (int tid) +{ + int ret; + gdb_vrregset_t regs; + + ret = ptrace (PTRACE_GETVRREGS, tid, 0, ®s); + if (ret < 0) + { + if (errno == EIO) + { + have_ptrace_getvrregs = 0; + return; + } + perror_with_name ("Unable to fetch AltiVec registers"); + } + supply_vrregset (®s); +} + static void fetch_ppc_registers (int tid) { int i; - int last_register = gdbarch_tdep (current_gdbarch)->ppc_mq_regnum; - - for (i = 0; i <= last_register; i++) + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + + for (i = 0; i <= tdep->ppc_mq_regnum; i++) fetch_register (tid, i); + if (have_ptrace_getvrregs) + if (tdep->ppc_vr0_regnum != -1 && tdep->ppc_vrsave_regnum != -1) + fetch_altivec_registers (tid); } /* Fetch registers from the child process. Fetch all registers if @@ -158,14 +278,14 @@ fetch_ppc_registers (int tid) void fetch_inferior_registers (int regno) { - /* Overload thread id onto process id */ + /* Overload thread id onto process id */ int tid = TIDGET (inferior_ptid); /* No thread id, just use process id */ if (tid == 0) tid = PIDGET (inferior_ptid); - if (regno == -1) + if (regno == -1) fetch_ppc_registers (tid); else fetch_register (tid, regno); @@ -173,6 +293,39 @@ fetch_inferior_registers (int regno) /* Store one register. */ static void +store_altivec_register (int tid, int regno) +{ + int ret; + int offset = 0; + gdb_vrregset_t regs; + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + int vrregsize = REGISTER_RAW_SIZE (tdep->ppc_vr0_regnum); + + ret = ptrace (PTRACE_GETVRREGS, tid, 0, ®s); + if (ret < 0) + { + if (errno == EIO) + { + have_ptrace_getvrregs = 0; + return; + } + perror_with_name ("Unable to fetch AltiVec register"); + } + + /* VSCR is fetched as a 16 bytes quantity, but it is really 4 bytes + long on the hardware. */ + if (regno == (tdep->ppc_vrsave_regnum - 1)) + offset = vrregsize - REGISTER_RAW_SIZE (tdep->ppc_vrsave_regnum); + + regcache_collect (regno, + regs + (regno - tdep->ppc_vr0_regnum) * vrregsize + offset); + + ret = ptrace (PTRACE_SETVRREGS, tid, 0, ®s); + if (ret < 0) + perror_with_name ("Unable to store AltiVec register"); +} + +static void store_register (int tid, int regno) { /* This isn't really an address. But ptrace thinks of it as one. */ @@ -182,11 +335,15 @@ store_register (int tid, int regno) unsigned int offset; /* Offset of registers within the u area. */ char *buf = alloca (MAX_REGISTER_RAW_SIZE); - if (regaddr == -1) + if (altivec_register_p (regno)) { + store_altivec_register (tid, regno); return; } + if (regaddr == -1) + return; + regcache_collect (regno, buf); for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE)) { @@ -204,13 +361,60 @@ store_register (int tid, int regno) } static void +fill_vrregset (gdb_vrregset_t *vrregsetp) +{ + int i; + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); + int num_of_vrregs = tdep->ppc_vrsave_regnum - tdep->ppc_vr0_regnum; + int vrregsize = REGISTER_RAW_SIZE (tdep->ppc_vr0_regnum); + int offset = vrregsize - REGISTER_RAW_SIZE (tdep->ppc_vrsave_regnum); + + for (i = 0; i < num_of_vrregs; i++) + { + /* The last 2 registers of this set are only 32 bit long, not + 128. Only VSCR is fetched as a 16 bytes quantity. */ + if (i == (tdep->ppc_vrsave_regnum - 1)) + regcache_collect (tdep->ppc_vr0_regnum + i, + *vrregsetp + i * vrregsize + offset); + else + regcache_collect (tdep->ppc_vr0_regnum + i, *vrregsetp + i * vrregsize); + } +} + +static void +store_altivec_registers (int tid) +{ + int ret; + gdb_vrregset_t regs; + + ret = ptrace (PTRACE_GETVRREGS, tid, 0, (int) ®s); + if (ret < 0) + { + if (errno == EIO) + { + have_ptrace_getvrregs = 0; + return; + } + perror_with_name ("Couldn't get AltiVec registers"); + } + + fill_vrregset (®s); + + if (ptrace (PTRACE_SETVRREGS, tid, 0, (int) ®s) < 0) + perror_with_name ("Couldn't write AltiVec registers"); +} + +static void store_ppc_registers (int tid) { int i; - int last_register = gdbarch_tdep (current_gdbarch)->ppc_mq_regnum; + struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); - for (i = 0; i <= last_register; i++) + for (i = 0; i <= tdep->ppc_mq_regnum; i++) store_register (tid, i); + if (have_ptrace_getvrregs) + if (tdep->ppc_vr0_regnum != -1 && tdep->ppc_vrsave_regnum != -1) + store_altivec_registers (tid); } void @@ -281,15 +485,15 @@ void supply_fpregset (gdb_fpregset_t * fpregsetp) { int regi; + for (regi = 0; regi < 32; regi++) supply_register (FP0_REGNUM + regi, (char *) (*fpregsetp + regi)); } - -/* Given a pointer to a floating point register set in /proc format - (fpregset_t *), update the register specified by REGNO from gdb's idea - of the current floating point register set. If REGNO is -1, update - them all. */ +/* Given a pointer to a floating point register set in /proc format + (fpregset_t *), update the register specified by REGNO from gdb's + idea of the current floating point register set. If REGNO is -1, + update them all. */ void fill_fpregset (gdb_fpregset_t *fpregsetp, int regno) {