From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1726) id 2A12C3858C39; Tue, 26 Mar 2024 18:58:59 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 2A12C3858C39 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1711479539; bh=gamBZoKrrYRAWEvDii1P4GBqxH0EihR1TGqPN2V26uU=; h=From:To:Subject:Date:From; b=T2keNrlKZqXCNMl8yK/V5+8LKnQC94E9xMOZeYDMijRrJ9ztwvjFqouMdmHCsS+yd ZsvQ53t7cj9PTOq/fYHsaIhNvSwau7ORjAxobpRImPtRKToKoTrB9dPMn6tBYI9y0U 5Nn+UyXsjgAnXEEgAOT6oekRDRmjdExVls3f9MOA= Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable From: Andrew Burgess To: gdb-cvs@sourceware.org Subject: [binutils-gdb] Revert "gdb/gdbserver: share x86/linux tdesc caching" X-Act-Checkin: binutils-gdb X-Git-Author: Andrew Burgess X-Git-Refname: refs/heads/master X-Git-Oldrev: 57d8b51d901585a07524ece1188b1892b207e950 X-Git-Newrev: 69324a74e344e640e0c2d4e76e4e4dfd3368cd76 Message-Id: <20240326185859.2A12C3858C39@sourceware.org> Date: Tue, 26 Mar 2024 18:58:59 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=3Dbinutils-gdb.git;h=3D69324a74e344= e640e0c2d4e76e4e4dfd3368cd76 commit 69324a74e344e640e0c2d4e76e4e4dfd3368cd76 Author: Andrew Burgess Date: Tue Mar 26 18:52:17 2024 +0000 Revert "gdb/gdbserver: share x86/linux tdesc caching" =20 This reverts commit 198ff6ff819c240545f9fc68b39636fd376d4ba9. Diff: --- gdb/amd64-linux-tdep.c | 31 +++++ gdb/i386-linux-tdep.c | 30 +++-- gdb/nat/x86-linux-tdesc.c | 287 ---------------------------------------= ---- gdb/nat/x86-linux-tdesc.h | 56 ++------- gdbserver/Makefile.in | 4 - gdbserver/configure.srv | 2 - gdbserver/linux-amd64-ipa.cc | 1 + gdbserver/linux-i386-ipa.cc | 1 + gdbserver/linux-x86-low.cc | 1 + gdbserver/linux-x86-tdesc.cc | 285 +++++++++++++++++++++++++++++++++++++++= ++- gdbserver/linux-x86-tdesc.h | 50 ++++++++ 11 files changed, 393 insertions(+), 355 deletions(-) diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c index e149034de21..7e0900dc6f9 100644 --- a/gdb/amd64-linux-tdep.c +++ b/gdb/amd64-linux-tdep.c @@ -1579,6 +1579,37 @@ amd64_linux_record_signal (struct gdbarch *gdbarch, return 0; } =20 +const target_desc * +amd64_linux_read_description (uint64_t xcr0_features_bit, bool is_x32) +{ + static target_desc *amd64_linux_tdescs \ + [2/*AVX*/][2/*MPX*/][2/*AVX512*/][2/*PKRU*/] =3D {}; + static target_desc *x32_linux_tdescs \ + [2/*AVX*/][2/*AVX512*/][2/*PKRU*/] =3D {}; + + target_desc **tdesc; + + if (is_x32) + { + tdesc =3D &x32_linux_tdescs[(xcr0_features_bit & X86_XSTATE_AVX) ? 1= : 0 ] + [(xcr0_features_bit & X86_XSTATE_AVX512) ? 1 : 0] + [(xcr0_features_bit & X86_XSTATE_PKRU) ? 1 : 0]; + } + else + { + tdesc =3D &amd64_linux_tdescs[(xcr0_features_bit & X86_XSTATE_AVX) ?= 1 : 0] + [(xcr0_features_bit & X86_XSTATE_MPX) ? 1 : 0] + [(xcr0_features_bit & X86_XSTATE_AVX512) ? 1 : 0] + [(xcr0_features_bit & X86_XSTATE_PKRU) ? 1 : 0]; + } + + if (*tdesc =3D=3D NULL) + *tdesc =3D amd64_create_target_description (xcr0_features_bit, is_x32, + true, true); + + return *tdesc; +} + /* Get Linux/x86 target description from core dump. */ =20 static const struct target_desc * diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c index ed1442236e8..f5f7a36bf36 100644 --- a/gdb/i386-linux-tdep.c +++ b/gdb/i386-linux-tdep.c @@ -681,12 +681,29 @@ i386_linux_core_read_x86_xsave_layout (struct gdbarch= *gdbarch, layout) !=3D 0; } =20 -/* See nat/x86-linux-tdesc.h. */ +/* See i386-linux-tdep.h. */ =20 -void -x86_linux_post_init_tdesc (target_desc *tdesc, bool is_64bit) +const struct target_desc * +i386_linux_read_description (uint64_t xcr0) { - /* Nothing. */ + if (xcr0 =3D=3D 0) + return NULL; + + static struct target_desc *i386_linux_tdescs \ + [2/*X87*/][2/*SSE*/][2/*AVX*/][2/*MPX*/][2/*AVX512*/][2/*PKRU*/] =3D {= }; + struct target_desc **tdesc; + + tdesc =3D &i386_linux_tdescs[(xcr0 & X86_XSTATE_X87) ? 1 : 0] + [(xcr0 & X86_XSTATE_SSE) ? 1 : 0] + [(xcr0 & X86_XSTATE_AVX) ? 1 : 0] + [(xcr0 & X86_XSTATE_MPX) ? 1 : 0] + [(xcr0 & X86_XSTATE_AVX512) ? 1 : 0] + [(xcr0 & X86_XSTATE_PKRU) ? 1 : 0]; + + if (*tdesc =3D=3D NULL) + *tdesc =3D i386_create_target_description (xcr0, true, false); + + return *tdesc; } =20 /* Get Linux/x86 target description from core dump. */ @@ -699,10 +716,7 @@ i386_linux_core_read_description (struct gdbarch *gdba= rch, /* Linux/i386. */ x86_xsave_layout layout; uint64_t xcr0 =3D i386_linux_core_read_xsave_info (abfd, layout); - - const struct target_desc *tdesc; - if (xcr0 !=3D 0) - tdesc =3D i386_linux_read_description (xcr0); + const struct target_desc *tdesc =3D i386_linux_read_description (xcr0); =20 if (tdesc !=3D NULL) return tdesc; diff --git a/gdb/nat/x86-linux-tdesc.c b/gdb/nat/x86-linux-tdesc.c index c438dfae84f..be7014d2b5f 100644 --- a/gdb/nat/x86-linux-tdesc.c +++ b/gdb/nat/x86-linux-tdesc.c @@ -38,8 +38,6 @@ #include #include =20 -#ifndef IN_PROCESS_AGENT - /* See nat/x86-linux-tdesc.h. */ =20 const target_desc * @@ -124,288 +122,3 @@ x86_linux_tdesc_for_tid (int tid, enum tribool *have_= ptrace_getregset, =20 gdb_assert_not_reached ("failed to return tdesc"); } - -#endif /* !IN_PROCESS_AGENT */ - - - -/* A structure used to describe a single cpu feature that might, or might - not, be checked for when creating a target description for one of i386, - amd64, or x32. */ - -struct x86_tdesc_feature { - /* The cpu feature mask. This is a mask against an xcr0 value. */ - uint64_t feature; - - /* Is this feature checked when creating an i386 target description. */ - bool is_i386; - - /* Is this feature checked when creating an amd64 target description. */ - bool is_amd64; - - /* Is this feature checked when creating an x32 target description. */ - bool is_x32; -}; - -/* A constant table that describes all of the cpu features that are - checked when building a target description for i386, amd64, or x32. */ - -static constexpr x86_tdesc_feature x86_linux_all_tdesc_features[] =3D { - /* Feature, i386, amd64, x32. */ - { X86_XSTATE_PKRU, true, true, true }, - { X86_XSTATE_AVX512, true, true, true }, - { X86_XSTATE_AVX, true, true, true }, - { X86_XSTATE_MPX, true, true, false }, - { X86_XSTATE_SSE, true, false, false }, - { X86_XSTATE_X87, true, false, false } -}; - -/* Return a compile time constant which is a mask of all the cpu features - that are checked for when building an i386 target description. */ - -static constexpr uint64_t -x86_linux_i386_tdesc_feature_mask () -{ - uint64_t mask =3D 0; - - for (const auto &entry : x86_linux_all_tdesc_features) - if (entry.is_i386) - mask |=3D entry.feature; - - return mask; -} - -/* Return a compile time constant which is a mask of all the cpu features - that are checked for when building an amd64 target description. */ - -static constexpr uint64_t -x86_linux_amd64_tdesc_feature_mask () -{ - uint64_t mask =3D 0; - - for (const auto &entry : x86_linux_all_tdesc_features) - if (entry.is_amd64) - mask |=3D entry.feature; - - return mask; -} - -/* Return a compile time constant which is a mask of all the cpu features - that are checked for when building an x32 target description. */ - -static constexpr uint64_t -x86_linux_x32_tdesc_feature_mask () -{ - uint64_t mask =3D 0; - - for (const auto &entry : x86_linux_all_tdesc_features) - if (entry.is_x32) - mask |=3D entry.feature; - - return mask; -} - -/* Return a compile time constant which is a count of the number of cpu - features that are checked for when building an i386 target description.= */ - -static constexpr int -x86_linux_i386_tdesc_count () -{ - uint64_t count =3D 0; - - for (const auto &entry : x86_linux_all_tdesc_features) - if (entry.is_i386) - ++count; - - gdb_assert (count > 0); - - return (1 << count); -} - -/* Return a compile time constant which is a count of the number of cpu - features that are checked for when building an amd64 target description= . */ - -static constexpr int -x86_linux_amd64_tdesc_count () -{ - uint64_t count =3D 0; - - for (const auto &entry : x86_linux_all_tdesc_features) - if (entry.is_amd64) - ++count; - - gdb_assert (count > 0); - - return (1 << count); -} - -/* Return a compile time constant which is a count of the number of cpu - features that are checked for when building an x32 target description. = */ - -static constexpr int -x86_linux_x32_tdesc_count () -{ - uint64_t count =3D 0; - - for (const auto &entry : x86_linux_all_tdesc_features) - if (entry.is_x32) - ++count; - - gdb_assert (count > 0); - - return (1 << count); -} - -#ifdef IN_PROCESS_AGENT - -/* See linux-x86-tdesc.h. */ - -int -x86_linux_amd64_ipa_tdesc_count () -{ - return x86_linux_amd64_tdesc_count (); -} - -/* See linux-x86-tdesc.h. */ - -int -x86_linux_x32_ipa_tdesc_count () -{ - return x86_linux_x32_tdesc_count (); -} - -/* See linux-x86-tdesc.h. */ - -int -x86_linux_i386_ipa_tdesc_count () -{ - return x86_linux_i386_tdesc_count (); -} - -#endif /* IN_PROCESS_AGENT */ - -/* Convert an xcr0 value into an integer. The integer will be passed to - the in-process-agent where it will then be passed to - x86_linux_tdesc_idx_to_xcr0 to get back the xcr0 value. */ - -int -x86_linux_xcr0_to_tdesc_idx (uint64_t xcr0) -{ - /* The following table shows which features are checked for when creating - the target descriptions (see nat/x86-linux-tdesc.c), the feature order - represents the bit order within the generated index number. - - i386 | x87 sse mpx avx avx512 pkru - amd64 | mpx avx avx512 pkru - i32 | avx avx512 pkru - - The features are ordered so that for each mode (i386, amd64, i32) the - generated index will form a continuous range. */ - - int idx =3D 0; - - for (int i =3D 0; i < ARRAY_SIZE (x86_linux_all_tdesc_features); ++i) - { - if ((xcr0 & x86_linux_all_tdesc_features[i].feature) !=3D 0) - idx |=3D (1 << i); - } - - return idx; -} - - -#ifdef IN_PROCESS_AGENT - -/* Convert an index number (as returned from x86_linux_xcr0_to_tdesc_idx) - into an xcr0 value which can then be used to create a target - description. */ - -uint64_t -x86_linux_tdesc_idx_to_xcr0 (int idx) -{ - uint64_t xcr0 =3D 0; - - for (int i =3D 0; i < ARRAY_SIZE (x86_linux_all_tdesc_features); ++i) - { - if ((idx & (1 << i)) !=3D 0) - xcr0 |=3D x86_linux_all_tdesc_features[i].feature; - } - - return xcr0; -} - -#endif /* IN_PROCESS_AGENT */ - -#if defined __i386__ || !defined IN_PROCESS_AGENT - -/* A cache of all possible i386 target descriptions. */ - -static struct target_desc *i386_tdescs[x86_linux_i386_tdesc_count ()] =3D = { }; - -/* See nat/x86-linux-tdesc.h. */ - -const struct target_desc * -i386_linux_read_description (uint64_t xcr0) -{ - xcr0 &=3D x86_linux_i386_tdesc_feature_mask (); - int idx =3D x86_linux_xcr0_to_tdesc_idx (xcr0); - - gdb_assert (idx >=3D 0 && idx < x86_linux_i386_tdesc_count ()); - - target_desc **tdesc =3D &i386_tdescs[idx]; - - if (*tdesc =3D=3D nullptr) - { - *tdesc =3D i386_create_target_description (xcr0, true, false); - - x86_linux_post_init_tdesc (*tdesc, false); - } - - return *tdesc; -} -#endif - -#ifdef __x86_64__ - -/* A cache of all possible amd64 target descriptions. */ - -static target_desc *amd64_tdescs[x86_linux_amd64_tdesc_count ()] =3D { }; - -/* A cache of all possible x32 target descriptions. */ - -static target_desc *x32_tdescs[x86_linux_x32_tdesc_count ()] =3D { }; - -/* See nat/x86-linux-tdesc.h. */ - -const struct target_desc * -amd64_linux_read_description (uint64_t xcr0, bool is_x32) -{ - if (is_x32) - xcr0 &=3D x86_linux_x32_tdesc_feature_mask (); - else - xcr0 &=3D x86_linux_amd64_tdesc_feature_mask (); - - int idx =3D x86_linux_xcr0_to_tdesc_idx (xcr0); - - if (is_x32) - gdb_assert (idx >=3D 0 && idx < x86_linux_x32_tdesc_count ()); - else - gdb_assert (idx >=3D 0 && idx < x86_linux_amd64_tdesc_count ()); - - target_desc **tdesc =3D nullptr; - - if (is_x32) - tdesc =3D &x32_tdescs[idx]; - else - tdesc =3D &amd64_tdescs[idx]; - - if (*tdesc =3D=3D nullptr) - { - *tdesc =3D amd64_create_target_description (xcr0, is_x32, true, true= ); - - x86_linux_post_init_tdesc (*tdesc, true); - } - return *tdesc; -} - -#endif diff --git a/gdb/nat/x86-linux-tdesc.h b/gdb/nat/x86-linux-tdesc.h index 648fe0ed0b2..3727a8bf95e 100644 --- a/gdb/nat/x86-linux-tdesc.h +++ b/gdb/nat/x86-linux-tdesc.h @@ -24,8 +24,6 @@ =20 struct target_desc; =20 -#ifndef IN_PROCESS_AGENT - /* Return the target description for Linux thread TID. =20 When *HAVE_PTRACE_GETREGSET is TRIBOOL_UNKNOWN then the current value of @@ -59,57 +57,19 @@ x86_linux_tdesc_for_tid (int tid, enum tribool *have_pt= race_getregset, gdb::function_view xcr0_init_cb, const char *error_msg, uint64_t *xcr0_storage); =20 -#endif /* !IN_PROCESS_AGENT */ - #ifdef __x86_64__ =20 -/* Return the AMD64 target descriptions corresponding to XCR0 and IS_X32. = */ +/* Return the right amd64-linux target descriptions according to + XCR0_FEATURES_BIT and IS_X32. This is implemented separately in both + GDB and gdbserver. */ =20 -extern const target_desc *amd64_linux_read_description (uint64_t xcr0, - bool is_x32); +extern const target_desc *amd64_linux_read_description + (uint64_t xcr0_features_bit, bool is_x32); =20 -#endif /* __x86_64__ */ - -/* Return the i386 target description corresponding to XCR0. */ +#endif =20 +/* Return the target description according to XCR0. This is implemented + separately in both GDB and gdbserver. */ extern const struct target_desc *i386_linux_read_description (uint64_t xcr= 0); =20 -/* This function is called from amd64_linux_read_description and - i386_linux_read_description after a new target description has been - created, TDESC is the new target description, IS_64BIT will be true - when called from amd64_linux_read_description, otherwise IS_64BIT will - be false. If the *_linux_read_description functions found a cached - target description then this function will not be called. - - Both GDB and gdbserver have their own implementations of this - function. */ - -extern void x86_linux_post_init_tdesc (target_desc *tdesc, bool is_64bit); - -/* Convert an xcr0 value into an integer. The integer will be passed to - the in-process-agent where it will then be passed to - x86_linux_tdesc_idx_to_xcr0 to get back the xcr0 value. */ - -extern int x86_linux_xcr0_to_tdesc_idx (uint64_t xcr0); - - -#ifdef IN_PROCESS_AGENT - -/* Convert an index number (as returned from x86_linux_xcr0_to_tdesc_idx) - into an xcr0 value which can then be used to create a target - description. */ - -extern uint64_t x86_linux_tdesc_idx_to_xcr0 (int idx); - -/* Within the in-process-agent we need to pre-initialise all of the target - descriptions, to do this we need to know how many target descriptions - there are for each different target type. These functions return the - target description count for the relevant target. */ - -extern int x86_linux_amd64_ipa_tdesc_count (); -extern int x86_linux_x32_ipa_tdesc_count (); -extern int x86_linux_i386_ipa_tdesc_count (); - -#endif /* IN_PROCESS_AGENT */ - #endif /* NAT_X86_LINUX_TDESC_H */ diff --git a/gdbserver/Makefile.in b/gdbserver/Makefile.in index bd6f68e7f2c..c7120895a26 100644 --- a/gdbserver/Makefile.in +++ b/gdbserver/Makefile.in @@ -519,10 +519,6 @@ gdbsupport/%-ipa.o: ../gdbsupport/%.cc $(IPAGENT_COMPILE) $< $(POSTCOMPILE) =20 -nat/%-ipa.o: ../gdb/nat/%.c - $(IPAGENT_COMPILE) $< - $(POSTCOMPILE) - %-ipa.o: ../gdb/%.c $(IPAGENT_COMPILE) -x c++ $< $(POSTCOMPILE) diff --git a/gdbserver/configure.srv b/gdbserver/configure.srv index 36a457f21ed..7a2702d78bf 100644 --- a/gdbserver/configure.srv +++ b/gdbserver/configure.srv @@ -116,7 +116,6 @@ case "${gdbserver_host}" in srv_linux_btrace=3Dyes ipa_obj=3D"linux-i386-ipa.o linux-x86-tdesc-ipa.o" ipa_obj=3D"${ipa_obj} arch/i386-ipa.o" - ipa_obj=3D"${ipa_obj} nat/x86-linux-tdesc-ipa.o" ;; i[34567]86-*-mingw*) srv_regobj=3D"" srv_tgtobj=3D"x86-low.o nat/x86-dregs.o win32-low.o" @@ -381,7 +380,6 @@ case "${gdbserver_host}" in srv_linux_btrace=3Dyes ipa_obj=3D"linux-amd64-ipa.o linux-x86-tdesc-ipa.o" ipa_obj=3D"${ipa_obj} arch/amd64-ipa.o" - ipa_obj=3D"${ipa_obj} nat/x86-linux-tdesc-ipa.o" ;; x86_64-*-mingw*) srv_regobj=3D"" srv_tgtobj=3D"x86-low.o nat/x86-dregs.o" diff --git a/gdbserver/linux-amd64-ipa.cc b/gdbserver/linux-amd64-ipa.cc index afa6aab5bab..42de7d2da16 100644 --- a/gdbserver/linux-amd64-ipa.cc +++ b/gdbserver/linux-amd64-ipa.cc @@ -21,6 +21,7 @@ #include "server.h" #include #include "tracepoint.h" +#include "linux-x86-tdesc.h" #include "gdbsupport/x86-xstate.h" #include "nat/x86-linux-tdesc.h" =20 diff --git a/gdbserver/linux-i386-ipa.cc b/gdbserver/linux-i386-ipa.cc index f6d26f784af..246bcb9813b 100644 --- a/gdbserver/linux-i386-ipa.cc +++ b/gdbserver/linux-i386-ipa.cc @@ -21,6 +21,7 @@ #include "server.h" #include #include "tracepoint.h" +#include "linux-x86-tdesc.h" #include "gdbsupport/x86-xstate.h" #include "nat/x86-linux-tdesc.h" =20 diff --git a/gdbserver/linux-x86-low.cc b/gdbserver/linux-x86-low.cc index 7134d20dd7f..6dbefdb2f26 100644 --- a/gdbserver/linux-x86-low.cc +++ b/gdbserver/linux-x86-low.cc @@ -47,6 +47,7 @@ #include "nat/linux-nat.h" #include "nat/x86-linux.h" #include "nat/x86-linux-dregs.h" +#include "linux-x86-tdesc.h" #include "nat/x86-linux-tdesc.h" =20 #ifdef __x86_64__ diff --git a/gdbserver/linux-x86-tdesc.cc b/gdbserver/linux-x86-tdesc.cc index 39d1d51b8c0..87cf368a336 100644 --- a/gdbserver/linux-x86-tdesc.cc +++ b/gdbserver/linux-x86-tdesc.cc @@ -19,19 +19,292 @@ =20 #include "server.h" #include "tdesc.h" +#include "linux-x86-tdesc.h" +#include "arch/i386.h" +#include "gdbsupport/x86-xstate.h" +#ifdef __x86_64__ +#include "arch/amd64.h" +#endif #include "x86-tdesc.h" #include "nat/x86-linux-tdesc.h" =20 +/* A structure used to describe a single cpu feature that might, or might + not, be checked for when creating a target description for one of i386, + amd64, or x32. */ + +struct x86_tdesc_feature { + /* The cpu feature mask. This is a mask against an xcr0 value. */ + uint64_t feature; + + /* Is this feature checked when creating an i386 target description. */ + bool is_i386; + + /* Is this feature checked when creating an amd64 target description. */ + bool is_amd64; + + /* Is this feature checked when creating an x32 target description. */ + bool is_x32; +}; + +/* A constant table that describes all of the cpu features that are + checked when building a target description for i386, amd64, or x32. */ + +static constexpr x86_tdesc_feature x86_linux_all_tdesc_features[] =3D { + /* Feature, i386, amd64, x32. */ + { X86_XSTATE_PKRU, true, true, true }, + { X86_XSTATE_AVX512, true, true, true }, + { X86_XSTATE_AVX, true, true, true }, + { X86_XSTATE_MPX, true, true, false }, + { X86_XSTATE_SSE, true, false, false }, + { X86_XSTATE_X87, true, false, false } +}; + +/* Return a compile time constant which is a mask of all the cpu features + that are checked for when building an i386 target description. */ + +static constexpr uint64_t +x86_linux_i386_tdesc_feature_mask () +{ + uint64_t mask =3D 0; + + for (const auto &entry : x86_linux_all_tdesc_features) + if (entry.is_i386) + mask |=3D entry.feature; + + return mask; +} + +/* Return a compile time constant which is a mask of all the cpu features + that are checked for when building an amd64 target description. */ + +static constexpr uint64_t +x86_linux_amd64_tdesc_feature_mask () +{ + uint64_t mask =3D 0; + + for (const auto &entry : x86_linux_all_tdesc_features) + if (entry.is_amd64) + mask |=3D entry.feature; + + return mask; +} + +/* Return a compile time constant which is a mask of all the cpu features + that are checked for when building an x32 target description. */ + +static constexpr uint64_t +x86_linux_x32_tdesc_feature_mask () +{ + uint64_t mask =3D 0; + + for (const auto &entry : x86_linux_all_tdesc_features) + if (entry.is_x32) + mask |=3D entry.feature; + + return mask; +} + +/* Return a compile time constant which is a count of the number of cpu + features that are checked for when building an i386 target description.= */ + +static constexpr int +x86_linux_i386_tdesc_count () +{ + uint64_t count =3D 0; + + for (const auto &entry : x86_linux_all_tdesc_features) + if (entry.is_i386) + ++count; + + gdb_assert (count > 0); + + return (1 << count); +} + +/* Return a compile time constant which is a count of the number of cpu + features that are checked for when building an amd64 target description= . */ + +static constexpr int +x86_linux_amd64_tdesc_count () +{ + uint64_t count =3D 0; + + for (const auto &entry : x86_linux_all_tdesc_features) + if (entry.is_amd64) + ++count; + + gdb_assert (count > 0); + + return (1 << count); +} + +/* Return a compile time constant which is a count of the number of cpu + features that are checked for when building an x32 target description. = */ + +static constexpr int +x86_linux_x32_tdesc_count () +{ + uint64_t count =3D 0; + + for (const auto &entry : x86_linux_all_tdesc_features) + if (entry.is_x32) + ++count; + + gdb_assert (count > 0); + + return (1 << count); +} + +#ifdef IN_PROCESS_AGENT + +/* See linux-x86-tdesc.h. */ + +int +x86_linux_amd64_ipa_tdesc_count () +{ + return x86_linux_amd64_tdesc_count (); +} + +/* See linux-x86-tdesc.h. */ + +int +x86_linux_x32_ipa_tdesc_count () +{ + return x86_linux_x32_tdesc_count (); +} + +/* See linux-x86-tdesc.h. */ + +int +x86_linux_i386_ipa_tdesc_count () +{ + return x86_linux_i386_tdesc_count (); +} + +#endif /* IN_PROCESS_AGENT */ + +/* Convert an xcr0 value into an integer. The integer will be passed to + the in-process-agent where it will then be passed to + x86_linux_tdesc_idx_to_xcr0 to get back the xcr0 value. */ + +int +x86_linux_xcr0_to_tdesc_idx (uint64_t xcr0) +{ + /* The following table shows which features are checked for when creating + the target descriptions (see nat/x86-linux-tdesc.c), the feature order + represents the bit order within the generated index number. + + i386 | x87 sse mpx avx avx512 pkru + amd64 | mpx avx avx512 pkru + i32 | avx avx512 pkru + + The features are ordered so that for each mode (i386, amd64, i32) the + generated index will form a continuous range. */ + + int idx =3D 0; + + for (int i =3D 0; i < ARRAY_SIZE (x86_linux_all_tdesc_features); ++i) + { + if ((xcr0 & x86_linux_all_tdesc_features[i].feature) !=3D 0) + idx |=3D (1 << i); + } + + return idx; +} + + +#ifdef IN_PROCESS_AGENT + +/* Convert an index number (as returned from x86_linux_xcr0_to_tdesc_idx) + into an xcr0 value which can then be used to create a target + description. */ + +uint64_t +x86_linux_tdesc_idx_to_xcr0 (int idx) +{ + uint64_t xcr0 =3D 0; + + for (int i =3D 0; i < ARRAY_SIZE (x86_linux_all_tdesc_features); ++i) + { + if ((idx & (1 << i)) !=3D 0) + xcr0 |=3D x86_linux_all_tdesc_features[i].feature; + } + + return xcr0; +} + +#endif /* IN_PROCESS_AGENT */ + +#if defined __i386__ || !defined IN_PROCESS_AGENT + +/* A cache of all possible i386 target descriptions. */ + +static struct target_desc *i386_tdescs[x86_linux_i386_tdesc_count ()] =3D = { }; + /* See nat/x86-linux-tdesc.h. */ =20 -void -x86_linux_post_init_tdesc (target_desc *tdesc, bool is_64bit) +const struct target_desc * +i386_linux_read_description (uint64_t xcr0) { + xcr0 &=3D x86_linux_i386_tdesc_feature_mask (); + int idx =3D x86_linux_xcr0_to_tdesc_idx (xcr0); + + gdb_assert (idx >=3D 0 && idx < x86_linux_i386_tdesc_count ()); + + target_desc **tdesc =3D &i386_tdescs[idx]; + + if (*tdesc =3D=3D nullptr) + { + *tdesc =3D i386_create_target_description (xcr0, true, false); + + init_target_desc (*tdesc, i386_expedite_regs); + } + + return *tdesc; +} +#endif + #ifdef __x86_64__ - if (is_64bit) - init_target_desc (tdesc, amd64_expedite_regs); + +/* A cache of all possible amd64 target descriptions. */ + +static target_desc *amd64_tdescs[x86_linux_amd64_tdesc_count ()] =3D { }; + +/* A cache of all possible x32 target descriptions. */ + +static target_desc *x32_tdescs[x86_linux_x32_tdesc_count ()] =3D { }; + +/* See nat/x86-linux-tdesc.h. */ + +const struct target_desc * +amd64_linux_read_description (uint64_t xcr0, bool is_x32) +{ + if (is_x32) + xcr0 &=3D x86_linux_x32_tdesc_feature_mask (); else -#endif - init_target_desc (tdesc, i386_expedite_regs); + xcr0 &=3D x86_linux_amd64_tdesc_feature_mask (); + + int idx =3D x86_linux_xcr0_to_tdesc_idx (xcr0); + + if (is_x32) + gdb_assert (idx >=3D 0 && idx < x86_linux_x32_tdesc_count ()); + else + gdb_assert (idx >=3D 0 && idx < x86_linux_amd64_tdesc_count ()); + + target_desc **tdesc =3D nullptr; + + if (is_x32) + tdesc =3D &x32_tdescs[idx]; + else + tdesc =3D &amd64_tdescs[idx]; + + if (*tdesc =3D=3D nullptr) + { + *tdesc =3D amd64_create_target_description (xcr0, is_x32, true, true= ); + + init_target_desc (*tdesc, amd64_expedite_regs); + } + return *tdesc; } =20 +#endif diff --git a/gdbserver/linux-x86-tdesc.h b/gdbserver/linux-x86-tdesc.h new file mode 100644 index 00000000000..70456e4be44 --- /dev/null +++ b/gdbserver/linux-x86-tdesc.h @@ -0,0 +1,50 @@ +/* Low level support for x86 (i386 and x86-64), shared between gdbserver + and IPA. + + Copyright (C) 2016-2024 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . = */ + +#ifndef GDBSERVER_LINUX_X86_TDESC_H +#define GDBSERVER_LINUX_X86_TDESC_H + +/* Convert an xcr0 value into an integer. The integer will be passed to + the in-process-agent where it will then be passed to + x86_linux_tdesc_idx_to_xcr0 to get back the xcr0 value. */ + +extern int x86_linux_xcr0_to_tdesc_idx (uint64_t xcr0); + +#ifdef IN_PROCESS_AGENT + +/* Convert an index number (as returned from x86_linux_xcr0_to_tdesc_idx) + into an xcr0 value which can then be used to create a target + description. */ + +extern uint64_t x86_linux_tdesc_idx_to_xcr0 (int idx); + +/* Within the in-process-agent we need to pre-initialise all of the target + descriptions, to do this we need to know how many target descriptions + there are for each different target type. These functions return the + target description count for the relevant target. */ + +extern int x86_linux_amd64_ipa_tdesc_count (); +extern int x86_linux_x32_ipa_tdesc_count (); +extern int x86_linux_i386_ipa_tdesc_count (); + + +#endif /* IN_PROCESS_AGENT */ + +#endif /* GDBSERVER_LINUX_X86_TDESC_H */