From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out30-57.freemail.mail.aliyun.com (out30-57.freemail.mail.aliyun.com [115.124.30.57]) by sourceware.org (Postfix) with ESMTPS id 679453858C2D for ; Wed, 31 Aug 2022 11:42:57 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 679453858C2D X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R241e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=ay29a033018046051; MF=jiangshuai_li@linux.alibaba.com; NM=1; PH=DS; RN=2; SR=0; TI=SMTPD_---0VNr8h4A_1661946172; Received: from lijsh-VirtualBox.hz.ali.com(mailfrom:jiangshuai_li@linux.alibaba.com fp:SMTPD_---0VNr8h4A_1661946172) by smtp.aliyun-inc.com; Wed, 31 Aug 2022 19:42:53 +0800 From: Jiangshuai Li To: gdb-patches@sourceware.org Cc: Jiangshuai Li Subject: [PATCH] gdb/csky add unwinder for long branch cases Date: Wed, 31 Aug 2022 19:42:50 +0800 Message-Id: <20220831114250.7276-1-jiangshuai_li@linux.alibaba.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-21.0 required=5.0 tests=BAYES_00, ENV_AND_HDR_SPF_MATCH, GIT_PATCH_0, KAM_DMARC_STATUS, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE, UNPARSEABLE_RELAY, USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 31 Aug 2022 11:43:00 -0000 There are two sequences of instructions for long branch: 1. jmpi [pc+4] //insn code: 0xeac00001 .long addr 2. lrw t1, [pc+8] //insn code: 0xea8d0002 jmp t1 //insn code: 0x7834 nop //insn code: 0x6c03 .long addr --- gdb/csky-tdep.c | 60 ++++++++++++++++++++++++++++++++++++++++++++----- gdb/csky-tdep.h | 5 +++++ 2 files changed, 60 insertions(+), 5 deletions(-) diff --git a/gdb/csky-tdep.c b/gdb/csky-tdep.c index ba53c1b10ca..3cd7a775f8d 100644 --- a/gdb/csky-tdep.c +++ b/gdb/csky-tdep.c @@ -2358,21 +2358,71 @@ static const struct frame_unwind csky_unwind_cache = { NULL }; +static CORE_ADDR +csky_check_long_branch (struct frame_info *frame, CORE_ADDR pc) +{ + gdb_byte buf[8]; + struct gdbarch *gdbarch = get_frame_arch (frame); + enum bfd_endian byte_order_for_code + = gdbarch_byte_order_for_code (gdbarch); + + if (target_read_memory (pc, buf, 8) == 0) + { + unsigned int data0 + = extract_unsigned_integer (buf, 4, byte_order_for_code); + unsigned int data1 + = extract_unsigned_integer (buf + 4, 4, byte_order_for_code); + + /* Case: jmpi [pc+4] : 0xeac00001 + .long addr */ + if (data0 == CSKY_JMPI_PC_4) + return data1; + + /* Case: lrw t1, [pc+8] : 0xea8d0002 + jmp t1 : 0x7834 + nop : 0x6c03 + .long addr */ + if ((data0 == CSKY_LRW_T1_PC_8) && (data1 == CSKY_JMP_T1_VS_NOP)) + { + if (target_read_memory (pc + 8, buf, 4) == 0) + return extract_unsigned_integer (buf, 4, byte_order_for_code); + } + return 0; + } + + return 0; +} static int csky_stub_unwind_sniffer (const struct frame_unwind *self, - struct frame_info *this_frame, - void **this_prologue_cache) + struct frame_info *this_frame, + void **this_prologue_cache) { - CORE_ADDR addr_in_block; + CORE_ADDR addr_in_block, pc; + gdb_byte dummy[4]; + const char *name; + CORE_ADDR start_addr; + /* Get pc */ addr_in_block = get_frame_address_in_block (this_frame); + pc = get_frame_pc (this_frame); - if (find_pc_partial_function (addr_in_block, NULL, NULL, NULL) == 0 - || in_plt_section (addr_in_block)) + if (in_plt_section (addr_in_block) + || target_read_memory (pc, dummy, 4) != 0) return 1; + /* Find the starting address and name of the function containing the PC. */ + if (find_pc_partial_function (pc, &name, &start_addr, NULL) == 0) + { + start_addr = csky_check_long_branch (this_frame, pc); + /* if not long branch, return 0. */ + if (start_addr != 0) + return 1; + + return 0; + } + return 0; } diff --git a/gdb/csky-tdep.h b/gdb/csky-tdep.h index f845b9ab744..dbdcd15b3a7 100644 --- a/gdb/csky-tdep.h +++ b/gdb/csky-tdep.h @@ -385,4 +385,9 @@ enum csky_regnum /* Macro for kernel 4.x */ #define CSKY_MOVI_R7_139 0x008bea07 +/* Macro for check long branch. */ +#define CSKY_JMPI_PC_4 0x1eac0 +#define CSKY_LRW_T1_PC_8 0x2ea8d +#define CSKY_JMP_T1_VS_NOP 0x6c037834 + #endif -- 2.25.1