From 311e0e178f76fae8ab14085387d526bc9280a499 Mon Sep 17 00:00:00 2001
From: Marek Marecki <marekjm@ozro.pw>
Date: Fri, 26 May 2023 01:35:02 +0200
Subject: [PATCH] Basic implementation for AA instruction

It does not check if enough memory is allocated and blindly creates the
pointer. The check is a TODO.
---
 new/Makefile          |  5 ++++
 new/src/vm/ins.cpp    |  3 ---
 new/src/vm/ins/aa.cpp | 61 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 66 insertions(+), 3 deletions(-)
 create mode 100644 new/src/vm/ins/aa.cpp

diff --git a/new/Makefile b/new/Makefile
index cd55407d6..91bd7a368 100644
--- a/new/Makefile
+++ b/new/Makefile
@@ -194,12 +194,16 @@ $(BUILD)/tools/exec/asm: \
 	$(BUILD)/arch/arch.o \
 	$(BUILD)/arch/ops.o
 
+VIUA_INSTRUCTION_IMPLS=\
+					   $(BUILD)/vm/ins/aa.o
+
 $(BUILD)/tools/exec/vm: \
 	$(BUILD)/support/tty.o \
 	$(BUILD)/support/string.o \
 	$(BUILD)/vm/core.o \
 	$(BUILD)/vm/elf.o \
 	$(BUILD)/vm/ins.o \
+	$(VIUA_INSTRUCTION_IMPLS) \
 	$(BUILD)/vm/types.o \
 	$(BUILD)/vm/types/traits.o \
 	$(BUILD)/runtime/pid.o \
@@ -212,6 +216,7 @@ $(BUILD)/tools/exec/repl: \
 	$(BUILD)/vm/core.o \
 	$(BUILD)/vm/elf.o \
 	$(BUILD)/vm/ins.o \
+	$(VIUA_INSTRUCTION_IMPLS) \
 	$(BUILD)/vm/types.o \
 	$(BUILD)/vm/types/traits.o \
 	$(BUILD)/support/string.o \
diff --git a/new/src/vm/ins.cpp b/new/src/vm/ins.cpp
index 5d8ea78fa..2188eac57 100644
--- a/new/src/vm/ins.cpp
+++ b/new/src/vm/ins.cpp
@@ -2064,9 +2064,6 @@ auto execute(LM const op, Stack& stack, ip_type const ip) -> void
             throw abort_execution{ip, "invalid unit in memory instruction: " + std::to_string(unit)};
     }
 }
-auto execute(AA const, Stack&, ip_type const) -> void
-{
-}
 auto execute(AD const, Stack&, ip_type const) -> void
 {
 }
diff --git a/new/src/vm/ins/aa.cpp b/new/src/vm/ins/aa.cpp
new file mode 100644
index 000000000..2e124bdb4
--- /dev/null
+++ b/new/src/vm/ins/aa.cpp
@@ -0,0 +1,61 @@
+/*
+ *  Copyright (C) 2021-2023 Marek Marecki
+ *
+ *  This file is part of Viua VM.
+ *
+ *  Viua VM 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.
+ *
+ *  Viua VM 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 Viua VM.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <endian.h>
+
+#include <algorithm>
+#include <functional>
+#include <iomanip>
+#include <iostream>
+#include <limits>
+#include <optional>
+#include <utility>
+#include <vector>
+
+#include <viua/arch/arch.h>
+#include <viua/support/fdstream.h>
+#include <viua/vm/ins.h>
+
+
+namespace viua {
+extern viua::support::fdstream TRACE_STREAM;
+}
+
+namespace viua::vm::ins {
+using namespace viua::arch::ins;
+using viua::vm::Stack;
+using ip_type = viua::arch::instruction_type const*;
+
+auto execute(AA const op, Stack& stack, ip_type const ip) -> void
+{
+    auto const size = get_value(stack, op.instruction.in, ip).get<uint64_t>();
+    auto const alignment[[maybe_unused]] = (1 << op.instruction.spec);
+
+    // FIXME Ensure that enough memory is available to satisfy both size and
+    // alignment request.
+
+    auto const old_sb = stack.proc->stack_break;
+    stack.proc->stack_break += size;
+    stack.frames.back().saved.sbrk = stack.proc->stack_break;
+
+    auto& registers = stack.frames.back().registers;
+    auto out        = get_proxy(registers, op.instruction.out, ip);
+    out = old_sb;
+}
+}  // namespace viua::vm::ins
-- 
2.38.5