target/arm: Add infrastructure for disas_sme

This includes the build rules for the decoder, and the
new file for translation, but excludes any instructions.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220708151540.18136-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm/meson.build

@@ -1,5 +1,6 @@
 gen = [
   decodetree.process('sve.decode', extra_args: '--decode=disas_sve'),
+  decodetree.process('sme.decode', extra_args: '--decode=disas_sme'),
   decodetree.process('neon-shared.decode', extra_args: '--decode=disas_neon_shared'),
   decodetree.process('neon-dp.decode', extra_args: '--decode=disas_neon_dp'),
   decodetree.process('neon-ls.decode', extra_args: '--decode=disas_neon_ls'),
@@ -50,6 +51,7 @@ arm_ss.add(when: 'TARGET_AARCH64', if_true: files(
   'sme_helper.c',
   'translate-a64.c',
   'translate-sve.c',
+  'translate-sme.c',
 ))
 
 arm_softmmu_ss = ss.source_set()

target/arm/sme.decode

@@ -0,0 +1,20 @@
+# AArch64 SME instruction descriptions
+#
+#  Copyright (c) 2022 Linaro, Ltd
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, see <http://www.gnu.org/licenses/>.
+
+#
+# This file is processed by scripts/decodetree.py
+#

target/arm/translate-a64.c

@@ -14806,7 +14806,12 @@ static void aarch64_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
     }
 
     switch (extract32(insn, 25, 4)) {
-    case 0x0: case 0x1: case 0x3: /* UNALLOCATED */
+    case 0x0:
+        if (!extract32(insn, 31, 1) || !disas_sme(s, insn)) {
+            unallocated_encoding(s);
+        }
+        break;
+    case 0x1: case 0x3: /* UNALLOCATED */
         unallocated_encoding(s);
         break;
     case 0x2:

target/arm/translate-a64.h

@@ -146,6 +146,7 @@ static inline int pred_gvec_reg_size(DisasContext *s)
 }
 
 bool disas_sve(DisasContext *, uint32_t);
+bool disas_sme(DisasContext *, uint32_t);
 
 void gen_gvec_rax1(unsigned vece, uint32_t rd_ofs, uint32_t rn_ofs,
                    uint32_t rm_ofs, uint32_t opr_sz, uint32_t max_sz);

target/arm/translate-sme.c

@@ -0,0 +1,35 @@
+/*
+ * AArch64 SME translation
+ *
+ * Copyright (c) 2022 Linaro, Ltd
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "tcg/tcg-op.h"
+#include "tcg/tcg-op-gvec.h"
+#include "tcg/tcg-gvec-desc.h"
+#include "translate.h"
+#include "exec/helper-gen.h"
+#include "translate-a64.h"
+#include "fpu/softfloat.h"
+
+
+/*
+ * Include the generated decoder.
+ */
+
+#include "decode-sme.c.inc"