From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1585) id 658E9383943C; Wed, 18 May 2022 14:58:02 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 658E9383943C Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable From: Luis Machado To: gdb-cvs@sourceware.org Subject: [binutils-gdb] [AArch64] Return the regnum for PC (32) on aarch64 X-Act-Checkin: binutils-gdb X-Git-Author: Yichao Yu X-Git-Refname: refs/heads/master X-Git-Oldrev: 4bb8b8e9381bce9734454470ebd1572534e7514e X-Git-Newrev: 1fe8486103e482bcd6cd74fdbf79a7d2ab9b111f Message-Id: <20220518145802.658E9383943C@sourceware.org> Date: Wed, 18 May 2022 14:58:02 +0000 (GMT) X-BeenThere: gdb-cvs@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 May 2022 14:58:02 -0000 https://sourceware.org/git/gitweb.cgi?p=3Dbinutils-gdb.git;h=3D1fe8486103e4= 82bcd6cd74fdbf79a7d2ab9b111f commit 1fe8486103e482bcd6cd74fdbf79a7d2ab9b111f Author: Yichao Yu Date: Wed May 18 15:00:00 2022 +0100 [AArch64] Return the regnum for PC (32) on aarch64 =20 This will allow the unwind info to explicitly specify a different value for the return address from the link register. Such usage, although uncommon, is valid and useful for signal frames. It is also supported by aadwarf64 from ARM (Note 9 in [1]). =20 Ref https://sourceware.org/pipermail/gdb/2022-May/050091.html =20 [1] https://github.com/ARM-software/abi-aa/blob/2022Q1/aadwarf64/aadwar= f64.rst#dwarf-register-names =20 Signed-off-by: Luis Machado Diff: --- gdb/aarch64-tdep.c | 3 ++ gdb/aarch64-tdep.h | 1 + gdb/testsuite/gdb.arch/aarch64-unwind-pc.S | 48 +++++++++++++++++++ gdb/testsuite/gdb.arch/aarch64-unwind-pc.exp | 70 ++++++++++++++++++++++++= ++++ 4 files changed, 122 insertions(+) diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c index d0995bb9c48..c3abd3a4256 100644 --- a/gdb/aarch64-tdep.c +++ b/gdb/aarch64-tdep.c @@ -2219,6 +2219,9 @@ aarch64_dwarf_reg_to_regnum (struct gdbarch *gdbarch,= int reg) if (reg =3D=3D AARCH64_DWARF_SP) return AARCH64_SP_REGNUM; =20 + if (reg =3D=3D AARCH64_DWARF_PC) + return AARCH64_PC_REGNUM; + if (reg >=3D AARCH64_DWARF_V0 && reg <=3D AARCH64_DWARF_V0 + 31) return AARCH64_V0_REGNUM + reg - AARCH64_DWARF_V0; =20 diff --git a/gdb/aarch64-tdep.h b/gdb/aarch64-tdep.h index 057525e68f4..8efacd5de0f 100644 --- a/gdb/aarch64-tdep.h +++ b/gdb/aarch64-tdep.h @@ -34,6 +34,7 @@ struct regset; /* AArch64 Dwarf register numbering. */ #define AARCH64_DWARF_X0 0 #define AARCH64_DWARF_SP 31 +#define AARCH64_DWARF_PC 32 #define AARCH64_DWARF_RA_SIGN_STATE 34 #define AARCH64_DWARF_V0 64 #define AARCH64_DWARF_SVE_VG 46 diff --git a/gdb/testsuite/gdb.arch/aarch64-unwind-pc.S b/gdb/testsuite/gdb= .arch/aarch64-unwind-pc.S new file mode 100644 index 00000000000..6cc4f80e349 --- /dev/null +++ b/gdb/testsuite/gdb.arch/aarch64-unwind-pc.S @@ -0,0 +1,48 @@ +/* Copyright 2022 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 . = */ + + .text + .globl main + .type main,#function +main: + .cfi_startproc + stp x29, x30, [sp, -16]! + .cfi_def_cfa sp, 16 + .cfi_offset x29, 0 + .cfi_offset x30, 8 + bl test_func + ldp x29, x30, [sp], 16 + .cfi_restore x29 + .cfi_restore x30 + .cfi_def_cfa sp, 0 + mov x0, 0 + ret + .cfi_endproc + + .globl test_func +test_func: + .cfi_startproc + // Unwind x30 to a different value + // CFA_val_expression x30 const2u 0x1234 + .cfi_escape 0x16, 30, 0x03, 0x0a, 0x34, 0x12 + // CFA_val_expression pc breg30 0 + .cfi_escape 0x16, 32, 0x02, 0x8e, 0x00 + mov x0, x30 + .cfi_register 32, x0 + mov x30, 0x1234 + ret x0 + .cfi_endproc diff --git a/gdb/testsuite/gdb.arch/aarch64-unwind-pc.exp b/gdb/testsuite/g= db.arch/aarch64-unwind-pc.exp new file mode 100644 index 00000000000..105b9a9cc3a --- /dev/null +++ b/gdb/testsuite/gdb.arch/aarch64-unwind-pc.exp @@ -0,0 +1,70 @@ +# Copyright 2022 Free Software Foundation, Inc. + +# 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 . + +# This file is part of the gdb testsuite. + +# Test explicitly unwinding the PC DWARF register on aarch64 + +if {![is_aarch64_target]} then { + verbose "Skipping ${gdb_test_file_name}." + return +} + +standard_testfile .S + +if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } { + return -1 +} + +if ![runto_main] { + return -1 +} + +proc test_reg_vals {} { + gdb_test "p \$pc - &main" "=3D 8" "p \$pc" + gdb_test "p/x \$x30" "=3D 0x1234" "p \$x30" +} + +proc test_unwind_pc { inst } { + gdb_test "si" "$inst" "single step" + gdb_test "backtrace" \ + ".*#1.*in main ().*" \ + "backtrace" + gdb_test "up" "in main ().*" "parent frame" + test_reg_vals +} + +# Ready to enter the function +gdb_test "si" "bl test_func" "call site" +# Step through the 3 instructions in the function to make sure that +# we have the same unwind info throughout. +with_test_prefix "1st stepi" { + test_unwind_pc "mov x0, x30" +} +with_test_prefix "2nd stepi" { + test_unwind_pc "mov x30, 0x1234" +} +with_test_prefix "3rd stepi" { + test_unwind_pc "ret x0" +} +# Check again after we returned +with_test_prefix "final" { + # Check that we've stepped out (si prints out the new function name) + gdb_test "si" ".*main *().*" "single step out" + gdb_test "backtrace" \ + "#0\[\t \]+main ().*" \ + "backtrace" + test_reg_vals +}