From patchwork Thu Nov 15 19:02:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Darrington X-Patchwork-Id: 30150 Received: (qmail 95212 invoked by alias); 15 Nov 2018 19:02:33 -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 95176 invoked by uid 89); 15 Nov 2018 19:02:33 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-25.1 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_PASS autolearn=ham version=3.3.2 spammy=sk:return_, regcache, H*MI:john X-HELO: jocasta.intra Received: from de.cellform.com (HELO jocasta.intra) (88.217.224.109) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 15 Nov 2018 19:02:31 +0000 Received: from jocasta.intra (localhost [127.0.0.1]) by jocasta.intra (8.15.2/8.15.2/Debian-8) with ESMTPS id wAFJ2SvJ002005 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 15 Nov 2018 20:02:28 +0100 Received: (from john@localhost) by jocasta.intra (8.15.2/8.15.2/Submit) id wAFJ2RLh002004; Thu, 15 Nov 2018 20:02:28 +0100 From: John Darrington To: gdb-patches@sourceware.org Cc: John Darrington Subject: [PATCH 2/2] GDB: S12Z: new function s12z_extract_return_value Date: Thu, 15 Nov 2018 20:02:25 +0100 Message-Id: <20181115190225.1959-1-john@darrington.wattle.id.au> Make gdb aware of the return values of functions which return in registers. gdb/ChangeLog: * s12z-tdep.c (s12z_extract_return_value): New function. (inv_reg_perm) New array. (s12z_return_value): Populate readbuf if non-null. --- gdb/s12z-tdep.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 61 insertions(+), 1 deletion(-) diff --git a/gdb/s12z-tdep.c b/gdb/s12z-tdep.c index bd0bd7c001..3da88523f7 100644 --- a/gdb/s12z-tdep.c +++ b/gdb/s12z-tdep.c @@ -37,7 +37,9 @@ #define N_PHYSICAL_REGISTERS (S12Z_N_REGISTERS - 2) -/* A permutation of all the physical registers. */ +/* A permutation of all the physical registers. Indexing this array + with an integer from gdb's internal representation will return the + register enum. */ static const int reg_perm[N_PHYSICAL_REGISTERS] = { REG_D0, @@ -55,6 +57,16 @@ static const int reg_perm[N_PHYSICAL_REGISTERS] = REG_CCW }; +/* The inverse of the above permutation. Indexing this + array with a register enum (e.g. REG_D2) will return the register + number in gdb's internal representation. */ +static const int inv_reg_perm[N_PHYSICAL_REGISTERS] = + { + 2, 3, 4, 5, /* d2, d3, d4, d5 */ + 0, 1, /* d0, d1 */ + 6, 7, /* d6, d7 */ + 8, 9, 10, 11, 12 /* x, y, s, p, ccw */ + }; /* Return the name of the register REGNUM. */ static const char * @@ -467,11 +479,59 @@ s12z_print_registers_info (struct gdbarch *gdbarch, + +static void +s12z_extract_return_value (struct type *type, struct regcache *regcache, + void *valbuf) +{ + int reg = -1; + + gdb_byte buf[4]; + + switch (TYPE_LENGTH (type)) + { + case 0: /* Nothing to do */ + return; + + case 1: + reg = REG_D0; + break; + + case 2: + reg = REG_D2; + break; + + case 3: + reg = REG_X; + break; + + case 4: + reg = REG_D6; + break; + + default: + error (_("bad size for return value")); + return; + } + + regcache->cooked_read (inv_reg_perm[reg], buf); + memcpy (valbuf, buf, TYPE_LENGTH (type)); +} + static enum return_value_convention s12z_return_value (struct gdbarch *gdbarch, struct value *function, struct type *type, struct regcache *regcache, gdb_byte *readbuf, const gdb_byte *writebuf) { + if (TYPE_CODE (type) == TYPE_CODE_STRUCT + || TYPE_CODE (type) == TYPE_CODE_UNION + || TYPE_CODE (type) == TYPE_CODE_ARRAY + || TYPE_LENGTH (type) > 4) + return RETURN_VALUE_STRUCT_CONVENTION; + + if (readbuf) + s12z_extract_return_value (type, regcache, readbuf); + return RETURN_VALUE_REGISTER_CONVENTION; }