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author | Indu Bhagat <indu.bhagat@oracle.com> | 2022-12-16 22:01:51 -0800 |
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committer | Indu Bhagat <indu.bhagat@oracle.com> | 2022-12-16 22:01:51 -0800 |
commit | 28f69152b99fd3a774e9bb9e66496cb1d7fd03b9 (patch) | |
tree | 656e578c608e7b7a7b4d4f6a8ca18cb034988fe5 /gas | |
parent | 4604c7294166199f89a0122ee35095d7e0cd2d07 (diff) | |
download | fsf-binutils-gdb-28f69152b99fd3a774e9bb9e66496cb1d7fd03b9.zip fsf-binutils-gdb-28f69152b99fd3a774e9bb9e66496cb1d7fd03b9.tar.gz fsf-binutils-gdb-28f69152b99fd3a774e9bb9e66496cb1d7fd03b9.tar.bz2 |
gas: sframe: add support for .cfi_negate_ra_state
DW_CFA_AARCH64_negate_ra_state in aarch64 is multiplexed with
DW_CFA_GNU_window_save in the DWARF format.
Remove the common-empty-4 testcase because the generated SFrame section
will not be be empty anymore. A relevant test will be added in a later
commit.
ChangeLog:
* gas/gen-sframe.c (sframe_v1_set_fre_info): Add new argument
for mangled_ra_p.
(sframe_set_fre_info): Likewise.
(output_sframe_row_entry): Handle mangled_ra_p.
(sframe_row_entry_new): Reset mangled_ra_p.
(sframe_row_entry_initialize): Initialize mangled_ra_p.
(sframe_xlate_do_gnu_window_save): New definition.
(sframe_do_cfi_insn): Handle DW_CFA_GNU_window_save.
* gas/gen-sframe.h (struct sframe_row_entry): New member.
(struct sframe_version_ops): Add a new argument for
mangled_ra_p.
* gas/testsuite/gas/cfi-sframe/cfi-sframe.exp: Remove test.
* gas/testsuite/gas/cfi-sframe/common-empty-4.d: Removed.
* gas/testsuite/gas/cfi-sframe/common-empty-4.s: Removed.
Diffstat (limited to 'gas')
-rw-r--r-- | gas/gen-sframe.c | 42 | ||||
-rw-r--r-- | gas/gen-sframe.h | 6 | ||||
-rw-r--r-- | gas/testsuite/gas/cfi-sframe/cfi-sframe.exp | 1 | ||||
-rw-r--r-- | gas/testsuite/gas/cfi-sframe/common-empty-4.d | 14 | ||||
-rw-r--r-- | gas/testsuite/gas/cfi-sframe/common-empty-4.s | 17 |
5 files changed, 39 insertions, 41 deletions
diff --git a/gas/gen-sframe.c b/gas/gen-sframe.c index 075720f..9baf20b 100644 --- a/gas/gen-sframe.c +++ b/gas/gen-sframe.c @@ -243,10 +243,11 @@ static struct sframe_version_ops sframe_ver_ops; static unsigned char sframe_v1_set_fre_info (unsigned int base_reg, unsigned int num_offsets, - unsigned int offset_size) + unsigned int offset_size, bool mangled_ra_p) { unsigned char fre_info; fre_info = SFRAME_V1_FRE_INFO (base_reg, num_offsets, offset_size); + fre_info = SFRAME_V1_FRE_INFO_UPDATE_MANGLED_RA_P (mangled_ra_p, fre_info); return fre_info; } @@ -275,10 +276,10 @@ sframe_set_version (uint32_t sframe_version __attribute__((unused))) static unsigned char sframe_set_fre_info (unsigned int base_reg, unsigned int num_offsets, - unsigned int offset_size) + unsigned int offset_size, bool mangled_ra_p) { return sframe_ver_ops.set_fre_info (base_reg, num_offsets, - offset_size); + offset_size, mangled_ra_p); } /* SFrame set func info. */ @@ -507,7 +508,7 @@ output_sframe_row_entry (symbolS *fde_start_addr, fre_num_offsets = get_fre_num_offsets (sframe_fre); fre_offset_size = sframe_get_fre_offset_size (sframe_fre); fre_info = sframe_set_fre_info (fre_base_reg, fre_num_offsets, - fre_offset_size); + fre_offset_size, sframe_fre->mangled_ra_p); out_one (fre_info); idx = sframe_fre_offset_func_map_index (fre_offset_size); @@ -845,6 +846,9 @@ sframe_row_entry_new (void) for the supported arches. */ fre->cfa_base_reg = -1; fre->merge_candidate = true; + /* Reset the mangled RA status bit to zero by default. We will initialize it in + sframe_row_entry_initialize () with the sticky bit if set. */ + fre->mangled_ra_p = false; return fre; } @@ -890,6 +894,9 @@ sframe_row_entry_initialize (struct sframe_row_entry *cur_fre, cur_fre->bp_offset = prev_fre->bp_offset; cur_fre->ra_loc = prev_fre->ra_loc; cur_fre->ra_offset = prev_fre->ra_offset; + /* Treat RA mangling as a sticky bit. It retains its value until another + .cfi_negate_ra_state is seen. */ + cur_fre->mangled_ra_p = prev_fre->mangled_ra_p; } /* Translate DW_CFA_advance_loc into SFrame context. @@ -1150,6 +1157,23 @@ sframe_xlate_do_restore (struct sframe_xlate_ctx *xlate_ctx, return SFRAME_XLATE_OK; } +/* Translate DW_CFA_GNU_window_save into SFrame context. + Return SFRAME_XLATE_OK if success. */ + +static int +sframe_xlate_do_gnu_window_save (struct sframe_xlate_ctx *xlate_ctx, + struct cfi_insn_data *cfi_insn ATTRIBUTE_UNUSED) +{ + struct sframe_row_entry *cur_fre = xlate_ctx->cur_fre; + + gas_assert (cur_fre); + /* Toggle the mangled RA status bit. */ + cur_fre->mangled_ra_p = !cur_fre->mangled_ra_p; + cur_fre->merge_candidate = false; + + return SFRAME_XLATE_OK; +} + /* Process CFI_INSN and update the translation context with the FRE information. @@ -1195,6 +1219,11 @@ sframe_do_cfi_insn (struct sframe_xlate_ctx *xlate_ctx, case DW_CFA_restore: err = sframe_xlate_do_restore (xlate_ctx, cfi_insn); break; + /* DW_CFA_AARCH64_negate_ra_state is multiplexed with + DW_CFA_GNU_window_save. */ + case DW_CFA_GNU_window_save: + err = sframe_xlate_do_gnu_window_save (xlate_ctx, cfi_insn); + break; case DW_CFA_undefined: case DW_CFA_same_value: break; @@ -1207,10 +1236,7 @@ sframe_do_cfi_insn (struct sframe_xlate_ctx *xlate_ctx, - ... Following skipped operations do, however, impact the asynchronicity: - - CFI_escape, - - DW_CFA_GNU_window_save, - - DW_CFA_AARCH64_negate_ra_state (multiplexed with - DW_CFA_GNU_window_save) */ + - CFI_escape */ err = SFRAME_XLATE_ERR_NOTREPRESENTED; // printf (_("SFrame Unsupported or unknown Dwarf CFI number: %#x\n"), op); diff --git a/gas/gen-sframe.h b/gas/gen-sframe.h index 93af499..5d5702a 100644 --- a/gas/gen-sframe.h +++ b/gas/gen-sframe.h @@ -50,6 +50,9 @@ struct sframe_row_entry on it. */ bool merge_candidate; + /* Whether the return address is mangled with pauth code. */ + bool mangled_ra_p; + /* Track CFA base (architectural) register ID. */ unsigned int cfa_base_reg; /* Offset from the CFA base register for recovering CFA. */ @@ -140,7 +143,8 @@ struct sframe_version_ops { unsigned char format_version; /* SFrame format version. */ /* set SFrame FRE info. */ - unsigned char (*set_fre_info) (unsigned int, unsigned int, unsigned int); + unsigned char (*set_fre_info) (unsigned int, unsigned int, unsigned int, + bool); /* set SFrame Func info. */ unsigned char (*set_func_info) (unsigned int, unsigned int); }; diff --git a/gas/testsuite/gas/cfi-sframe/cfi-sframe.exp b/gas/testsuite/gas/cfi-sframe/cfi-sframe.exp index eb6da61..8129e86 100644 --- a/gas/testsuite/gas/cfi-sframe/cfi-sframe.exp +++ b/gas/testsuite/gas/cfi-sframe/cfi-sframe.exp @@ -82,7 +82,6 @@ if { ([istarget "x86_64-*-*"] || [istarget "aarch64*-*-*"]) \ run_dump_test "common-empty-1" run_dump_test "common-empty-2" run_dump_test "common-empty-3" - run_dump_test "common-empty-4" } # x86-64 specific tests diff --git a/gas/testsuite/gas/cfi-sframe/common-empty-4.d b/gas/testsuite/gas/cfi-sframe/common-empty-4.d deleted file mode 100644 index f7a6062..0000000 --- a/gas/testsuite/gas/cfi-sframe/common-empty-4.d +++ /dev/null @@ -1,14 +0,0 @@ -#as: --gsframe -#objdump: --sframe=.sframe -#name: SFrame supports only default return column -#... -Contents of the SFrame section .sframe: - - Header : - - Version: SFRAME_VERSION_1 - Flags: NONE - Num FDEs: 0 - Num FREs: 0 - -#pass diff --git a/gas/testsuite/gas/cfi-sframe/common-empty-4.s b/gas/testsuite/gas/cfi-sframe/common-empty-4.s deleted file mode 100644 index f97ca2f..0000000 --- a/gas/testsuite/gas/cfi-sframe/common-empty-4.s +++ /dev/null @@ -1,17 +0,0 @@ -## ARMv8.3 addded support a new security feature named Pointer Authentication. The -## main idea behind this is to use the unused bits in the pointer values. -## Each pointer is patched with a PAC before writing to memory, and is verified -## before using it. -## When the pointers are mangled, the unwinder needs to know so it can mask off -## the PAC from the pointer value to recover the return address, and -## conversely, skip doing so if the pointers are not mangled. -## -## .cfi_negate_ra_state CFI directive is used to convey this information. -## -## SFrame does not have any means to represent this information at this time. - .cfi_startproc - .long 0 - .cfi_def_cfa_offset 16 - .cfi_negate_ra_state - .long 0 - .cfi_endproc |