From patchwork Fri Dec 1 16:27:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Marchi X-Patchwork-Id: 81155 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 2A2B838618A3 for ; Fri, 1 Dec 2023 16:32:52 +0000 (GMT) X-Original-To: gdb-patches@sourceware.org Delivered-To: gdb-patches@sourceware.org Received: from simark.ca (simark.ca [158.69.221.121]) by sourceware.org (Postfix) with ESMTPS id 9DBEE385E004 for ; Fri, 1 Dec 2023 16:31:59 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 9DBEE385E004 Authentication-Results: sourceware.org; dmarc=fail (p=none dis=none) header.from=efficios.com Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=efficios.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 9DBEE385E004 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=158.69.221.121 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701448322; cv=none; b=gEQZYI0MizPyR2akMq/zxXeoGnz+vbkXTxPQiat9MYIRkLJu+9ocu9vfVD+AbVcFPQPxQHKQ2Wm5OjZ8qTkXC+Fh0hpyj1vRphZYl0JRnkPvdhiqqvO5S9devyXzYgImQ57L863pKUNfR79cstOCpeFeRsywWgh58iOSkFcm2Sg= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701448322; c=relaxed/simple; bh=WtcrcDv/rof8R/hAj8q6xKXbWp4KHF/7Oxi4/bmija8=; h=From:To:Subject:Date:Message-ID:MIME-Version; b=InkkWcAZBvnczXLnQEX+X7v5NBvV1dBKkMFpBAIhAR/Rd4VxgwQT2JXy3ER+RzjTpN/VUktiXQDpGmGF8wyuoRO/RPTwiICIasrjfnEHJyFG3mw9MRjNWh1I4nQXYS492JibVUnkd07/owa4HwdoSwqlRMxjafXYCsPr+hOugVc= ARC-Authentication-Results: i=1; server2.sourceware.org Received: from smarchi-efficios.internal.efficios.com (192-222-143-198.qc.cable.ebox.net [192.222.143.198]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id DAA521E0BB; Fri, 1 Dec 2023 11:31:58 -0500 (EST) From: Simon Marchi To: gdb-patches@sourceware.org Cc: Luis Machado , John Baldwin , "Aktemur, Tankut Baris" , Simon Marchi , John Baldwin Subject: [PATCH 17/24] gdb: add gdbarch_pseudo_register_write that takes a frame Date: Fri, 1 Dec 2023 11:27:30 -0500 Message-ID: <20231201162751.741751-18-simon.marchi@efficios.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231201162751.741751-1-simon.marchi@efficios.com> References: <20231201162751.741751-1-simon.marchi@efficios.com> MIME-Version: 1.0 X-Spam-Status: No, score=-3496.6 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_NONE, KAM_DMARC_STATUS, SPF_HELO_PASS, SPF_SOFTFAIL, TXREP, T_SCC_BODY_TEXT_LINE 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: 2.1.30 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: gdb-patches-bounces+patchwork=sourceware.org@sourceware.org New in v2: - Add missing comments, fix typos Add a new variant of gdbarch_pseudo_register_write that takes a frame_info in order to write raw registers. Use this new method when available: - in put_frame_register, when trying to write a pseudo register to a given frame - in regcache::cooked_write No implementation is migrated to use this new method (that will come in subsequent patches), so no behavior change is expected here. The objective is to fix writing pseudo registers to non-current frames. See previous commit "gdb: read pseudo register through frame" for a more detailed explanation. Change-Id: Ie7fe364a15a4d86c2ecb09de2b4baa08c45555ac Reviewed-By: John Baldwin --- gdb/frame.c | 9 +++++- gdb/gdbarch-gen.h | 15 ++++++++- gdb/gdbarch.c | 32 ++++++++++++++++++ gdb/gdbarch_components.py | 19 +++++++++++ gdb/regcache.c | 4 +++ gdb/value.c | 68 +++++++++++++++++++++++++++++++++++++++ gdb/value.h | 22 +++++++++++++ 7 files changed, 167 insertions(+), 2 deletions(-) diff --git a/gdb/frame.c b/gdb/frame.c index a9cad1dca8fb..5f4c8c621a04 100644 --- a/gdb/frame.c +++ b/gdb/frame.c @@ -1453,7 +1453,14 @@ put_frame_register (frame_info_ptr next_frame, int regnum, break; } case lval_register: - get_thread_regcache (inferior_thread ())->cooked_write (realnum, buf); + /* Not sure if that's always true... but we have a problem if not. */ + gdb_assert (size == register_size (gdbarch, realnum)); + + if (realnum < gdbarch_num_regs (gdbarch) + || !gdbarch_pseudo_register_write_p (gdbarch)) + get_thread_regcache (inferior_thread ())->cooked_write (realnum, buf); + else + gdbarch_pseudo_register_write (gdbarch, next_frame, realnum, buf); break; default: error (_("Attempt to assign to an unmodifiable value.")); diff --git a/gdb/gdbarch-gen.h b/gdb/gdbarch-gen.h index 7b34dce3cfc8..80d40136c379 100644 --- a/gdb/gdbarch-gen.h +++ b/gdb/gdbarch-gen.h @@ -200,12 +200,25 @@ typedef struct value * (gdbarch_pseudo_register_read_value_ftype) (struct gdbarc extern struct value * gdbarch_pseudo_register_read_value (struct gdbarch *gdbarch, frame_info_ptr next_frame, int cookednum); extern void set_gdbarch_pseudo_register_read_value (struct gdbarch *gdbarch, gdbarch_pseudo_register_read_value_ftype *pseudo_register_read_value); +/* Write bytes in BUF to pseudo register with number PSEUDO_REG_NUM. + + Raw registers backing the pseudo register should be written to using + NEXT_FRAME. */ + +extern bool gdbarch_pseudo_register_write_p (struct gdbarch *gdbarch); + +typedef void (gdbarch_pseudo_register_write_ftype) (struct gdbarch *gdbarch, frame_info_ptr next_frame, int pseudo_reg_num, gdb::array_view buf); +extern void gdbarch_pseudo_register_write (struct gdbarch *gdbarch, frame_info_ptr next_frame, int pseudo_reg_num, gdb::array_view buf); +extern void set_gdbarch_pseudo_register_write (struct gdbarch *gdbarch, gdbarch_pseudo_register_write_ftype *pseudo_register_write); + /* Write bytes to a pseudo register. This is marked as deprecated because it gets passed a regcache for implementations to write raw registers in. This doesn't work for unwound frames, where the raw registers backing the pseudo registers may have been - saved elsewhere. */ + saved elsewhere. + + Implementations should be migrated to implement pseudo_register_write instead. */ extern bool gdbarch_deprecated_pseudo_register_write_p (struct gdbarch *gdbarch); diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c index e198d339f6ba..d584305fefb2 100644 --- a/gdb/gdbarch.c +++ b/gdb/gdbarch.c @@ -74,6 +74,7 @@ struct gdbarch gdbarch_virtual_frame_pointer_ftype *virtual_frame_pointer = legacy_virtual_frame_pointer; gdbarch_pseudo_register_read_ftype *pseudo_register_read = nullptr; gdbarch_pseudo_register_read_value_ftype *pseudo_register_read_value = nullptr; + gdbarch_pseudo_register_write_ftype *pseudo_register_write = nullptr; gdbarch_deprecated_pseudo_register_write_ftype *deprecated_pseudo_register_write = nullptr; int num_regs = -1; int num_pseudo_regs = 0; @@ -330,6 +331,7 @@ verify_gdbarch (struct gdbarch *gdbarch) /* Skip verify of virtual_frame_pointer, invalid_p == 0 */ /* Skip verify of pseudo_register_read, has predicate. */ /* Skip verify of pseudo_register_read_value, has predicate. */ + /* Skip verify of pseudo_register_write, has predicate. */ /* Skip verify of deprecated_pseudo_register_write, has predicate. */ if (gdbarch->num_regs == -1) log.puts ("\n\tnum_regs"); @@ -649,6 +651,12 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file) gdb_printf (file, "gdbarch_dump: pseudo_register_read_value = <%s>\n", host_address_to_string (gdbarch->pseudo_register_read_value)); + gdb_printf (file, + "gdbarch_dump: gdbarch_pseudo_register_write_p() = %d\n", + gdbarch_pseudo_register_write_p (gdbarch)); + gdb_printf (file, + "gdbarch_dump: pseudo_register_write = <%s>\n", + host_address_to_string (gdbarch->pseudo_register_write)); gdb_printf (file, "gdbarch_dump: gdbarch_deprecated_pseudo_register_write_p() = %d\n", gdbarch_deprecated_pseudo_register_write_p (gdbarch)); @@ -1902,6 +1910,30 @@ set_gdbarch_pseudo_register_read_value (struct gdbarch *gdbarch, gdbarch->pseudo_register_read_value = pseudo_register_read_value; } +bool +gdbarch_pseudo_register_write_p (struct gdbarch *gdbarch) +{ + gdb_assert (gdbarch != NULL); + return gdbarch->pseudo_register_write != NULL; +} + +void +gdbarch_pseudo_register_write (struct gdbarch *gdbarch, frame_info_ptr next_frame, int pseudo_reg_num, gdb::array_view buf) +{ + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->pseudo_register_write != NULL); + if (gdbarch_debug >= 2) + gdb_printf (gdb_stdlog, "gdbarch_pseudo_register_write called\n"); + gdbarch->pseudo_register_write (gdbarch, next_frame, pseudo_reg_num, buf); +} + +void +set_gdbarch_pseudo_register_write (struct gdbarch *gdbarch, + gdbarch_pseudo_register_write_ftype pseudo_register_write) +{ + gdbarch->pseudo_register_write = pseudo_register_write; +} + bool gdbarch_deprecated_pseudo_register_write_p (struct gdbarch *gdbarch) { diff --git a/gdb/gdbarch_components.py b/gdb/gdbarch_components.py index ee3fd2b69454..4352f7066512 100644 --- a/gdb/gdbarch_components.py +++ b/gdb/gdbarch_components.py @@ -418,6 +418,23 @@ never be called. predicate=True, ) +Method( + comment=""" +Write bytes in BUF to pseudo register with number PSEUDO_REG_NUM. + +Raw registers backing the pseudo register should be written to using +NEXT_FRAME. +""", + type="void", + name="pseudo_register_write", + params=[ + ("frame_info_ptr", "next_frame"), + ("int", "pseudo_reg_num"), + ("gdb::array_view", "buf"), + ], + predicate=True, +) + Method( comment=""" Write bytes to a pseudo register. @@ -426,6 +443,8 @@ This is marked as deprecated because it gets passed a regcache for implementations to write raw registers in. This doesn't work for unwound frames, where the raw registers backing the pseudo registers may have been saved elsewhere. + +Implementations should be migrated to implement pseudo_register_write instead. """, type="void", name="deprecated_pseudo_register_write", diff --git a/gdb/regcache.c b/gdb/regcache.c index 0e3316aaa096..6140a05f02b2 100644 --- a/gdb/regcache.c +++ b/gdb/regcache.c @@ -911,6 +911,10 @@ regcache::cooked_write (int regnum, gdb::array_view src) if (regnum < num_raw_registers ()) raw_write (regnum, src); + else if (gdbarch_pseudo_register_write_p (m_descr->gdbarch)) + gdbarch_pseudo_register_write + (m_descr->gdbarch, get_next_frame_sentinel_okay (get_current_frame ()), + regnum, src); else gdbarch_deprecated_pseudo_register_write (m_descr->gdbarch, this, regnum, src.data ()); diff --git a/gdb/value.c b/gdb/value.c index 9d826d4fdbed..f61949bf9422 100644 --- a/gdb/value.c +++ b/gdb/value.c @@ -4057,6 +4057,23 @@ pseudo_from_raw_part (frame_info_ptr next_frame, int pseudo_reg_num, /* See value.h. */ +void +pseudo_to_raw_part (frame_info_ptr next_frame, + gdb::array_view pseudo_buf, + int raw_reg_num, int raw_offset) +{ + int raw_reg_size + = register_size (frame_unwind_arch (next_frame), raw_reg_num); + + /* When overflowing a register, put_frame_register_bytes writes to the + subsequent registers. We don't want that behavior here, so make sure + the write is wholly within register RAW_REG_NUM. */ + gdb_assert (raw_offset + pseudo_buf.size () <= raw_reg_size); + put_frame_register_bytes (next_frame, raw_reg_num, raw_offset, pseudo_buf); +} + +/* See value.h. */ + value * pseudo_from_concat_raw (frame_info_ptr next_frame, int pseudo_reg_num, int raw_reg_1_num, int raw_reg_2_num) @@ -4080,6 +4097,29 @@ pseudo_from_concat_raw (frame_info_ptr next_frame, int pseudo_reg_num, return pseudo_reg_val; } +/* See value.h. */ + +void +pseudo_to_concat_raw (frame_info_ptr next_frame, + gdb::array_view pseudo_buf, + int raw_reg_1_num, int raw_reg_2_num) +{ + int src_offset = 0; + gdbarch *arch = frame_unwind_arch (next_frame); + + int raw_reg_1_size = register_size (arch, raw_reg_1_num); + put_frame_register_bytes (next_frame, raw_reg_1_num, 0, + pseudo_buf.slice (src_offset, raw_reg_1_size)); + src_offset += raw_reg_1_size; + + int raw_reg_2_size = register_size (arch, raw_reg_2_num); + put_frame_register_bytes (next_frame, raw_reg_2_num, 0, + pseudo_buf.slice (src_offset, raw_reg_2_size)); + src_offset += raw_reg_2_size; + + gdb_assert (src_offset == pseudo_buf.size ()); +} + /* See value.h. */ value * @@ -4111,6 +4151,34 @@ pseudo_from_concat_raw (frame_info_ptr next_frame, int pseudo_reg_num, return pseudo_reg_val; } +/* See value.h. */ + +void +pseudo_to_concat_raw (frame_info_ptr next_frame, + gdb::array_view pseudo_buf, + int raw_reg_1_num, int raw_reg_2_num, int raw_reg_3_num) +{ + int src_offset = 0; + gdbarch *arch = frame_unwind_arch (next_frame); + + int raw_reg_1_size = register_size (arch, raw_reg_1_num); + put_frame_register_bytes (next_frame, raw_reg_1_num, 0, + pseudo_buf.slice (src_offset, raw_reg_1_size)); + src_offset += raw_reg_1_size; + + int raw_reg_2_size = register_size (arch, raw_reg_2_num); + put_frame_register_bytes (next_frame, raw_reg_2_num, 0, + pseudo_buf.slice (src_offset, raw_reg_2_size)); + src_offset += raw_reg_2_size; + + int raw_reg_3_size = register_size (arch, raw_reg_3_num); + put_frame_register_bytes (next_frame, raw_reg_3_num, 0, + pseudo_buf.slice (src_offset, raw_reg_3_size)); + src_offset += raw_reg_3_size; + + gdb_assert (src_offset == pseudo_buf.size ()); +} + /* Implementation of the convenience function $_isvoid. */ static struct value * diff --git a/gdb/value.h b/gdb/value.h index 935d9ebfd8c9..d7bda1e8d2c9 100644 --- a/gdb/value.h +++ b/gdb/value.h @@ -1661,6 +1661,13 @@ struct scoped_array_length_limiting value *pseudo_from_raw_part (frame_info_ptr next_frame, int pseudo_reg_num, int raw_reg_num, int raw_offset); +/* Write PSEUDO_BUF, the contents of a pseudo register, to part of raw register + RAW_REG_NUM starting at RAW_OFFSET. */ + +void pseudo_to_raw_part (frame_info_ptr next_frame, + gdb::array_view pseudo_buf, + int raw_reg_num, int raw_offset); + /* Create a value for pseudo register PSEUDO_REG_NUM by concatenating raw registers RAW_REG_1_NUM and RAW_REG_2_NUM. @@ -1670,10 +1677,25 @@ value *pseudo_from_raw_part (frame_info_ptr next_frame, int pseudo_reg_num, value *pseudo_from_concat_raw (frame_info_ptr next_frame, int pseudo_reg_num, int raw_reg_1_num, int raw_reg_2_num); +/* Write PSEUDO_BUF, the contents of a pseudo register, to the two raw registers + RAW_REG_1_NUM and RAW_REG_2_NUM. */ + +void pseudo_to_concat_raw (frame_info_ptr next_frame, + gdb::array_view pseudo_buf, + int raw_reg_1_num, int raw_reg_2_num); + /* Same as the above, but with three raw registers. */ value *pseudo_from_concat_raw (frame_info_ptr next_frame, int pseudo_reg_num, int raw_reg_1_num, int raw_reg_2_num, int raw_reg_3_num); +/* Write PSEUDO_BUF, the contents of a pseudo register, to the three raw + registers RAW_REG_1_NUM, RAW_REG_2_NUM and RAW_REG_3_NUM. */ + +void pseudo_to_concat_raw (frame_info_ptr next_frame, + gdb::array_view pseudo_buf, + int raw_reg_1_num, int raw_reg_2_num, + int raw_reg_3_num); + #endif /* !defined (VALUE_H) */