[ARM, sim] Fix build error and warnings

Newer GCC's have switched to -fno-common by default, and this breaks the build
for the ARM sim, like this:

binutils-gdb.git~gdb-8.3-release/sim/arm/maverick.c:65: multiple definition of `DSPsc'; libsim.a(wrapper.o):binutils-gdb.git~gdb-8.3-release/sim/arm/wrapper.c:134: first defined here
binutils-gdb.git~gdb-8.3-release/sim/arm/maverick.c:64: multiple definition of `DSPacc'; libsim.a(wrapper.o):binutils-gdb.git~gdb-8.3-release/sim/arm/wrapper.c:133: first defined here
binutils-gdb.git~gdb-8.3-release/sim/arm/maverick.c:63: multiple definition of `DSPregs'; libsim.a(wrapper.o):binutils-gdb.git~gdb-8.3-release/sim/arm/wrapper.c:132: first defined here

I also noticed a few warnings due to mismatching types, as follows:

../../../../repos/binutils-gdb/sim/arm/wrapper.c: In function ‘sim_create_inferior’:
../../../../repos/binutils-gdb/sim/arm/wrapper.c:335:16: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
       for (arg = argv; *arg != NULL; arg++)
                ^
../../../../repos/binutils-gdb/sim/arm/wrapper.c:342:8: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
    arg = argv;
        ^
../../../../repos/binutils-gdb/sim/arm/wrapper.c:345:13: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
    for (arg = argv; *arg != NULL; arg++)
             ^
The following patch fixes both of the above.

sim/arm/ChangeLog:

2019-12-06  Luis Machado  <luis.machado@linaro.org>

	* armemu.c (isize): Move this declaration ...
	* arminit.c (isize): ... here.
	* maverick.h: New file.
	* wrapper.c: Include "maverick.h".
	(<struct maverick_regs>, <union maverick_acc_regs>): Remove and update
	comment.
	(sim_create_inferior): Cast variables to proper type.
	* maverick.c: Include "maverick.h".
	(<struct maverick_regs>, <union maverick_acc_regs>): Move
	declarations to maverick.h and update comment.
	(DSPsc, DSPacc, DSPregs): Adjust comment.

Change-Id: I21db699d3b61b2de8c44053e47be4387285af28f

1 files changed, 46 insertions, 0 deletions

diff --git a/sim/arm/maverick.h b/sim/arm/maverick.h
new file mode 100644
index 0000000..2549d21
--- /dev/null
+++ b/sim/arm/maverick.h
@@ -0,0 +1,46 @@
+/*  maverick.h -- Cirrus/DSP co-processor interface header
+    Copyright (C) 2003-2019 Free Software Foundation, Inc.
+    Contributed by Aldy Hernandez (aldyh@redhat.com).
+
+    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 <http://www.gnu.org/licenses/>. */
+
+/* Define Co-Processor instruction handlers here.  */
+
+/* Here's ARMulator's DSP definition.  A few things to note:
+   1) it has 16 64-bit registers and 4 72-bit accumulators
+   2) you can only access its registers with MCR and MRC.  */
+
+struct maverick_regs
+{
+  union
+  {
+    int i;
+    float f;
+  } upper;
+
+  union
+  {
+    int i;
+    float f;
+  } lower;
+};
+
+union maverick_acc_regs
+{
+  long double ld;		/* Acc registers are 72-bits.  */
+};
+
+extern struct maverick_regs DSPregs[16];
+extern union maverick_acc_regs DSPacc[4];
+extern ARMword DSPsc;