From patchwork Wed Sep 19 16:41:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Burgess X-Patchwork-Id: 29472 Received: (qmail 88148 invoked by alias); 19 Sep 2018 16:41:49 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 87843 invoked by uid 89); 19 Sep 2018 16:41:48 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-26.4 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.2 spammy=OTHER, rv32, riscvtdepc, riscv-tdep.c X-HELO: mail-wm1-f66.google.com Received: from mail-wm1-f66.google.com (HELO mail-wm1-f66.google.com) (209.85.128.66) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 19 Sep 2018 16:41:46 +0000 Received: by mail-wm1-f66.google.com with SMTP id y2-v6so7006890wma.1 for ; Wed, 19 Sep 2018 09:41:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=embecosm.com; s=google; h=from:to:cc:subject:date:message-id; bh=aytwkdquLZGx6eZlnccfwyTfFgJPR5nAiYhgp3lzBxw=; b=OAU8tGzkpuW0ymGr7Pa/yFjMU5s3h8hWDpQCXIJxDZSzPf6/VjNGt2Mr1e80RfqxOL L7Im/POOCQnS7SX6mxeMHjL25fCzxsKSb4T3ZOYqRkAAgdckKz0YsNZqT3NcpuAtctnx XpIbaIsdMQJExMuHgtvWwi/If/gg4mRO4thihP3O2v2N/GGbk7xz6YytbOFnTmgwMrsB 5lt9ZtlfUM4j+f4Ms7Ufr+aFnCDWRqry8XLcHnbQJYSmW2z4qfvFA6NmWqy7iXy8rkBf 6myKShDaOlAjOstWfIysCDgej6O6HNxjGB3M5CrSun+Zz0jHjworeQtjHGwfpfsfUkP3 SCzA== Return-Path: Received: from localhost (host81-158-205-250.range81-158.btcentralplus.com. [81.158.205.250]) by smtp.gmail.com with ESMTPSA id 185-v6sm7920175wmy.38.2018.09.19.09.41.42 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 19 Sep 2018 09:41:42 -0700 (PDT) From: Andrew Burgess To: gdb-patches@sourceware.org Cc: jimw@sifive.com, palmer@sifive.com, Andrew Burgess Subject: [PATCH] gdb/riscv: Improve non-dwarf stack unwinding Date: Wed, 19 Sep 2018 17:41:38 +0100 Message-Id: <20180919164138.16480-1-andrew.burgess@embecosm.com> X-IsSubscribed: yes This commit improves the prologue scanning stack unwinder, to better support AUIPC, LUI, and more variants of ADD and ADDI. This allows unwinding over frames containing large local variables, where the frame size does not fit into a single instruction immediate, and is first loaded into a temporary register, before being added to the stack pointer. A new test is added that tests this behaviour. As there's nothing truely RiscV specific about this test I've added it into gdb.base, but as this depends on target specific code to perform the unwind it is possible that some targets might fail this new test. gdb/ChangeLog: * riscv-tdep.c (riscv_insn::decode): Decode c.lui. (riscv_scan_prologue): Split handling of AUIPC, LUI, ADD, ADDI, and NOP. gdb/testsuite/ChangeLog: * gdb.base/large-frame-1.c: New file. * gdb.base/large-frame-2.c: New file. * gdb.base/large-frame.exp: New file. * gdb.base/large-frame.h: New file. --- gdb/ChangeLog | 6 ++++ gdb/riscv-tdep.c | 59 ++++++++++++++++++++++------------ gdb/testsuite/ChangeLog | 7 ++++ gdb/testsuite/gdb.base/large-frame-1.c | 32 ++++++++++++++++++ gdb/testsuite/gdb.base/large-frame-2.c | 25 ++++++++++++++ gdb/testsuite/gdb.base/large-frame.exp | 57 ++++++++++++++++++++++++++++++++ gdb/testsuite/gdb.base/large-frame.h | 24 ++++++++++++++ 7 files changed, 189 insertions(+), 21 deletions(-) create mode 100644 gdb/testsuite/gdb.base/large-frame-1.c create mode 100644 gdb/testsuite/gdb.base/large-frame-2.c create mode 100644 gdb/testsuite/gdb.base/large-frame.exp create mode 100644 gdb/testsuite/gdb.base/large-frame.h diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c index 254914c9c7e..163c8ec231d 100644 --- a/gdb/riscv-tdep.c +++ b/gdb/riscv-tdep.c @@ -1227,7 +1227,11 @@ riscv_insn::decode (struct gdbarch *gdbarch, CORE_ADDR pc) m_imm.s = EXTRACT_RVC_ADDI4SPN_IMM (ival); } else if (is_c_lui_insn (ival)) - m_opcode = OTHER; + { + m_opcode = LUI; + m_rd = decode_register_index (ival, OP_SH_CRS1S); + m_imm.s = EXTRACT_RVC_LUI_IMM (ival); + } /* C_SD and C_FSW have the same opcode. C_SD is RV64 and RV128 only, and C_FSW is RV32 only. */ else if (xlen != 4 && is_c_sd_insn (ival)) @@ -1359,28 +1363,41 @@ riscv_scan_prologue (struct gdbarch *gdbarch, gdb_assert (insn.rs1 () < RISCV_NUM_INTEGER_REGS); regs[insn.rd ()] = pv_add_constant (regs[insn.rs1 ()], 0); } - else if ((insn.rd () == RISCV_GP_REGNUM - && (insn.opcode () == riscv_insn::AUIPC - || insn.opcode () == riscv_insn::LUI - || (insn.opcode () == riscv_insn::ADDI - && insn.rs1 () == RISCV_GP_REGNUM) - || (insn.opcode () == riscv_insn::ADD - && (insn.rs1 () == RISCV_GP_REGNUM - || insn.rs2 () == RISCV_GP_REGNUM)))) - || (insn.opcode () == riscv_insn::ADDI - && insn.rd () == RISCV_ZERO_REGNUM - && insn.rs1 () == RISCV_ZERO_REGNUM - && insn.imm_signed () == 0)) + else if ((insn.opcode () == riscv_insn::ADDI + && insn.rd () == RISCV_ZERO_REGNUM + && insn.rs1 () == RISCV_ZERO_REGNUM + && insn.imm_signed () == 0)) { - /* Handle: auipc gp, n - or: addi gp, gp, n - or: add gp, gp, reg - or: add gp, reg, gp - or: lui gp, n - or: add x0, x0, 0 (NOP) */ - /* These instructions are part of the prologue, but we don't need - to do anything special to handle them. */ + /* Handle: add x0, x0, 0 (NOP) */ } + else if (insn.opcode () == riscv_insn::AUIPC) + { + gdb_assert (insn.rd () < RISCV_NUM_INTEGER_REGS); + regs[insn.rd ()] = pv_constant (cur_pc + insn.imm_signed ()); + } + else if (insn.opcode () == riscv_insn::LUI) + { + /* Handle: lui REG, n + Where REG is not gp register. */ + gdb_assert (insn.rd () < RISCV_NUM_INTEGER_REGS); + regs[insn.rd ()] = pv_constant (insn.imm_signed ()); + } + else if (insn.opcode () == riscv_insn::ADDI) + { + /* Handle: addi REG1, REG2, IMM */ + gdb_assert (insn.rd () < RISCV_NUM_INTEGER_REGS); + gdb_assert (insn.rs1 () < RISCV_NUM_INTEGER_REGS); + regs[insn.rd ()] + = pv_add_constant (regs[insn.rs1 ()], insn.imm_signed ()); + } + else if (insn.opcode () == riscv_insn::ADD) + { + /* Handle: addi REG1, REG2, IMM */ + gdb_assert (insn.rd () < RISCV_NUM_INTEGER_REGS); + gdb_assert (insn.rs1 () < RISCV_NUM_INTEGER_REGS); + gdb_assert (insn.rs2 () < RISCV_NUM_INTEGER_REGS); + regs[insn.rd ()] = pv_add (regs[insn.rs1 ()], regs[insn.rs2 ()]); + } else { end_prologue_addr = cur_pc; diff --git a/gdb/testsuite/gdb.base/large-frame-1.c b/gdb/testsuite/gdb.base/large-frame-1.c new file mode 100644 index 00000000000..cd9c5ccdd0a --- /dev/null +++ b/gdb/testsuite/gdb.base/large-frame-1.c @@ -0,0 +1,32 @@ +/* This file is part of GDB, the GNU debugger. + + Copyright 2018 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 . */ + +#include "large-frame.h" + +__attribute__ ((noinline)) void +blah (int *a) +{ + asm ("" :: "m" (a) : "memory"); +} + +int +main () +{ + func (); + + return 0; +} diff --git a/gdb/testsuite/gdb.base/large-frame-2.c b/gdb/testsuite/gdb.base/large-frame-2.c new file mode 100644 index 00000000000..2491c347292 --- /dev/null +++ b/gdb/testsuite/gdb.base/large-frame-2.c @@ -0,0 +1,25 @@ +/* This file is part of GDB, the GNU debugger. + + Copyright 2018 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 . */ + +#include "large-frame.h" + +__attribute__ ((noinline)) int +func (void) +{ + int a[4096]; + blah (a); +} diff --git a/gdb/testsuite/gdb.base/large-frame.exp b/gdb/testsuite/gdb.base/large-frame.exp new file mode 100644 index 00000000000..00090da795e --- /dev/null +++ b/gdb/testsuite/gdb.base/large-frame.exp @@ -0,0 +1,57 @@ +# Copyright 2018 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. + +# This test was added to test GDB's ability to backtrace over a large +# stack frame for which there is no debug information. This should +# test the non-DWARF stack unwinder. +# +# The test was originally added for Risc-V where this case caused a +# problem at one point, however, there's nothing Risc-V specific in +# the test. + +proc run_test { opt_level } { + global srcfile srcfile2 binfile hex + + standard_testfile large-frame-1.c large-frame-2.c + + if {[prepare_for_testing_full "failed to prepare" \ + [list ${binfile}-${opt_level} debug \ + $srcfile [list debug] \ + $srcfile2 [list nodebug optimize=-$opt_level]]]} { + return + } + + if { ![runto_main] } then { + unsupported "runto main" + return + } + + gdb_breakpoint "blah" + gdb_continue_to_breakpoint "blah" + + gdb_test "backtrace" [multi_line \ + "#0 blah \[^\n\r\]+" \ + "#1 $hex in func \[^\n\r\]+" \ + "#2 $hex in main \[^\n\r\]+"] +} + +foreach opt { O0 O1 O2 } { + with_test_prefix "optimize=-$opt" { + run_test $opt + } +} + diff --git a/gdb/testsuite/gdb.base/large-frame.h b/gdb/testsuite/gdb.base/large-frame.h new file mode 100644 index 00000000000..17058a5efd2 --- /dev/null +++ b/gdb/testsuite/gdb.base/large-frame.h @@ -0,0 +1,24 @@ +/* This file is part of GDB, the GNU debugger. + + Copyright 2018 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 . */ + +#ifndef LARGE_FRAME_H +#define LARGE_FRAME_H + +extern void blah (int *); +extern int func (void); + +#endif /* LARGE_FRAME_H */