Re: RFA: Adjust PowerPC prologue analyzer for PIC

Daniel Jacobowitz
2006-01-23T01:49:56Z

On Thu, Dec 15, 2005 at 01:06:33PM -0700, Kevin Buettner wrote:
> On Sun, 11 Dec 2005 12:15:41 -0500
> Daniel Jacobowitz <drow@false.org> wrote:
>
> > 2005-12-10 Daniel Jacobowitz <dan@codesourcery.com>
> >
> > PR tdep/2029
> > Suggested by Till Straumann <strauman@slac.stanford.edu>:
> > * rs6000-tdep.c (skip_prologue): Update check for later mtlr
> > instructions. Handle PIC bcl.
>
> Okay.

Thanks. I've belatedly checked this in, along with the attached
testcase.

--
Daniel Jacobowitz
CodeSourcery

2006-01-22 Daniel Jacobowitz <dan@codesourcery.com>

* gdb.arch/powerpc-prologue.c, gdb.arch/powerpc-prologue.exp: New
files.

Index: gdb.arch/powerpc-prologue.c
===================================================================
RCS file: gdb.arch/powerpc-prologue.c
diff -N gdb.arch/powerpc-prologue.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gdb.arch/powerpc-prologue.c 23 Jan 2006 01:46:50 -0000
@@ -0,0 +1,53 @@
+/* Unwinder test program.
+
+ Copyright 2006 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 2 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#ifdef SYMBOL_PREFIX
+#define SYMBOL(str) SYMBOL_PREFIX #str
+#else
+#define SYMBOL(str) #str
+#endif
+
+void gdb2029 (void);
+
+int
+main (void)
+{
+ gdb2029 ();
+ return 0;
+}
+
+/* A typical PIC prologue from GCC. */
+
+asm(".text\n"
+ " .align 8\n"
+ SYMBOL (gdb2029) ":\n"
+ " stw %r1, -32(%r1)\n"
+ " mflr %r0\n"
+ " bcl- 20,31,.+4\n"
+ " stw %r30, 24(%r1)\n"
+ " mflr %r30\n"
+ " stw %r0, 36(%r1)\n"
+ " twge %r2, %r2\n"
+ " lwz %r0, 36(%r1)\n"
+ " lwz %r30, 24(%r1)\n"
+ " mtlr %r0\n"
+ " addi %r0, %r0, 32\n"
+ " blr");
Index: gdb.arch/powerpc-prologue.exp
===================================================================
RCS file: gdb.arch/powerpc-prologue.exp
diff -N gdb.arch/powerpc-prologue.exp
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gdb.arch/powerpc-prologue.exp 23 Jan 2006 01:46:50 -0000
@@ -0,0 +1,61 @@
+# Copyright 2006 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 2 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, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+# Test PowerPC prologue analyzer.
+
+# Do not run on AIX (where we won't be able to build the tests without
+# some surgery) or on PowerPC64 (ditto, dot symbols).
+if {[istarget *-*-aix*] || ![istarget "powerpc-*-*"]} then {
+ verbose "Skipping PowerPC prologue tests."
+ return
+}
+
+set testfile "powerpc-prologue"
+set srcfile ${testfile}.c
+set binfile ${objdir}/${subdir}/${testfile}
+
+# Don't use "debug", so that we don't have line information for the assembly
+# fragments.
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {}] != "" } {
+ untested "PowerPC prologue tests"
+ return -1
+}
+
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_load ${binfile}
+
+#
+# Run to `main' where we begin our tests.
+#
+
+if ![runto_main] then {
+ gdb_suppress_tests
+}
+
+# Testcase for PIC prologue.
+
+gdb_test "continue" "Program received signal SIGTRAP.*" "continue to PIC"
+
+gdb_test "backtrace 10" \
+ "#0\[ \t\]*$hex in gdb2029.*\r\n#1\[ \t\]*$hex in main.*" \
+ "backtrace in PIC"
+
+gdb_test "info frame" \
+ ".*Saved registers:.*r30 at.*r31 at.*pc at.*lr at.*" \
+ "saved registers in PIC"