target/ppc: Add infrastructure for prefixed insns

Signed-off-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20210601193528.2533031-4-matheus.ferst@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

target/ppc/cpu.h

@@ -144,6 +144,7 @@ enum {
     POWERPC_EXCP_ALIGN_PROT    = 0x04,  /* Access cross protection boundary  */
     POWERPC_EXCP_ALIGN_BAT     = 0x05,  /* Access cross a BAT/seg boundary   */
     POWERPC_EXCP_ALIGN_CACHE   = 0x06,  /* Impossible dcbz access            */
+    POWERPC_EXCP_ALIGN_INSN    = 0x07,  /* Pref. insn x-ing 64-byte boundary */
     /* Exception subtypes for POWERPC_EXCP_PROGRAM                           */
     /* FP exceptions                                                         */
     POWERPC_EXCP_FP            = 0x10,

target/ppc/insn32.decode

@@ -0,0 +1,18 @@
+#
+# Power ISA decode for 32-bit insns (opcode space 0)
+#
+# Copyright (c) 2021 Instituto de Pesquisas Eldorado (eldorado.org.br)
+#
+# 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/>.
+#

target/ppc/insn64.decode

@@ -0,0 +1,18 @@
+#
+# Power ISA decode for 64-bit prefixed insns (opcode space 0 and 1)
+#
+# Copyright (c) 2021 Instituto de Pesquisas Eldorado (eldorado.org.br)
+#
+# 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/>.
+#

target/ppc/meson.build

@@ -20,6 +20,15 @@ ppc_ss.add(when: 'CONFIG_TCG', if_true: files(
 
 ppc_ss.add(libdecnumber)
 
+gen = [
+  decodetree.process('insn32.decode',
+                     extra_args: '--static-decode=decode_insn32'),
+  decodetree.process('insn64.decode',
+                     extra_args: ['--static-decode=decode_insn64',
+                                  '--insnwidth=64']),
+]
+ppc_ss.add(gen)
+
 ppc_ss.add(when: 'CONFIG_KVM', if_true: files('kvm.c'), if_false: files('kvm-stub.c'))
 ppc_ss.add(when: 'CONFIG_USER_ONLY', if_true: files('user_only_helper.c'))
 

target/ppc/translate.c

@@ -7690,6 +7690,10 @@ static inline void set_avr64(int regno, TCGv_i64 src, bool high)
 # define REQUIRE_64BIT(CTX)  REQUIRE_INSNS_FLAGS(CTX, 64B)
 #endif
 
+#include "decode-insn32.c.inc"
+#include "decode-insn64.c.inc"
+#include "translate/fixedpoint-impl.c.inc"
+
 #include "translate/fp-impl.c.inc"
 
 #include "translate/vmx-impl.c.inc"
@@ -8850,11 +8854,18 @@ static bool ppc_tr_breakpoint_check(DisasContextBase *dcbase, CPUState *cs,
     return true;
 }
 
+static bool is_prefix_insn(DisasContext *ctx, uint32_t insn)
+{
+    REQUIRE_INSNS_FLAGS2(ctx, ISA310);
+    return opc1(insn) == 1;
+}
+
 static void ppc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs)
 {
     DisasContext *ctx = container_of(dcbase, DisasContext, base);
     PowerPCCPU *cpu = POWERPC_CPU(cs);
     CPUPPCState *env = cs->env_ptr;
+    target_ulong pc;
     uint32_t insn;
     bool ok;
 
@@ -8862,18 +8873,32 @@ static void ppc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs)
     LOG_DISAS("nip=" TARGET_FMT_lx " super=%d ir=%d\n",
               ctx->base.pc_next, ctx->mem_idx, (int)msr_ir);
 
-    ctx->cia = ctx->base.pc_next;
+    ctx->cia = pc = ctx->base.pc_next;
-    insn = translator_ldl_swap(env, ctx->base.pc_next, need_byteswap(ctx));
+    insn = translator_ldl_swap(env, pc, need_byteswap(ctx));
-    ctx->base.pc_next += 4;
+    ctx->base.pc_next = pc += 4;
 
-    ok = decode_legacy(cpu, ctx, insn);
+    if (!is_prefix_insn(ctx, insn)) {
+        ok = (decode_insn32(ctx, insn) ||
+              decode_legacy(cpu, ctx, insn));
+    } else if ((pc & 63) == 0) {
+        /*
+         * Power v3.1, section 1.9 Exceptions:
+         * attempt to execute a prefixed instruction that crosses a
+         * 64-byte address boundary (system alignment error).
+         */
+        gen_exception_err(ctx, POWERPC_EXCP_ALIGN, POWERPC_EXCP_ALIGN_INSN);
+        ok = true;
+    } else {
+        uint32_t insn2 = translator_ldl_swap(env, pc, need_byteswap(ctx));
+        ctx->base.pc_next = pc += 4;
+        ok = decode_insn64(ctx, deposit64(insn2, 32, 32, insn));
+    }
     if (!ok) {
         gen_invalid(ctx);
     }
 
     /* End the TB when crossing a page boundary. */
-    if (ctx->base.is_jmp == DISAS_NEXT &&
+    if (ctx->base.is_jmp == DISAS_NEXT && !(pc & ~TARGET_PAGE_MASK)) {
-        !(ctx->base.pc_next & ~TARGET_PAGE_MASK)) {
         ctx->base.is_jmp = DISAS_TOO_MANY;
     }
 

target/ppc/translate/fixedpoint-impl.c.inc

@@ -0,0 +1,18 @@
+/*
+ * Power ISA decode for Fixed-Point Facility instructions
+ *
+ * Copyright (c) 2021 Instituto de Pesquisas Eldorado (eldorado.org.br)
+ *
+ * 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/>.
+ */