blob: 39871767e51c09381be5dce69aebf2ca9317c7e2 [file] [log] [blame]
// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/globals.h"
#if defined(TARGET_ARCH_RISCV32) || defined(TARGET_ARCH_RISCV64)
#include "vm/runtime_entry.h"
#include "vm/simulator.h"
#include "vm/stub_code.h"
#if !defined(DART_PRECOMPILED_RUNTIME)
#include "vm/compiler/assembler/assembler.h"
#endif // !defined(DART_PRECOMPILED_RUNTIME)
namespace dart {
#define __ assembler->
uword RuntimeEntry::GetEntryPoint() const {
// Compute the effective address. When running under the simulator,
// this is a redirection address that forces the simulator to call
// into the runtime system.
uword entry = reinterpret_cast<uword>(function());
#if defined(USING_SIMULATOR)
// Redirection to leaf runtime calls supports a maximum of 4 arguments passed
// in registers (maximum 2 double arguments for leaf float runtime calls).
ASSERT(argument_count() >= 0);
ASSERT(!is_leaf() || (!is_float() && (argument_count() <= 4)) ||
(argument_count() <= 2));
Simulator::CallKind call_kind =
is_leaf() ? (is_float() ? Simulator::kLeafFloatRuntimeCall
: Simulator::kLeafRuntimeCall)
: Simulator::kRuntimeCall;
entry =
Simulator::RedirectExternalReference(entry, call_kind, argument_count());
#endif
return entry;
}
#if !defined(DART_PRECOMPILED_RUNTIME)
// Generate code to call into the stub which will call the runtime
// function. Input for the stub is as follows:
// SP : points to the arguments and return value array.
// T5 : address of the runtime function to call.
// T4 : number of arguments to the call.
void RuntimeEntry::CallInternal(const RuntimeEntry* runtime_entry,
compiler::Assembler* assembler,
intptr_t argument_count) {
if (runtime_entry->is_leaf()) {
ASSERT(argument_count == runtime_entry->argument_count());
COMPILE_ASSERT(!IsAbiPreservedRegister(PP));
// PP is a C volatile register.
// SP will be aligned to the C stack alignment.
__ mv(CALLEE_SAVED_TEMP, PP);
__ mv(CALLEE_SAVED_TEMP2, SP);
__ lx(TMP2,
compiler::Address(THR, Thread::OffsetFromThread(runtime_entry)));
__ sx(TMP2, compiler::Address(THR, Thread::vm_tag_offset()));
__ ReserveAlignedFrameSpace(0);
__ jalr(TMP2);
__ LoadImmediate(TMP2, VMTag::kDartTagId);
__ sx(TMP2, compiler::Address(THR, Thread::vm_tag_offset()));
__ mv(PP, CALLEE_SAVED_TEMP);
__ mv(SP, CALLEE_SAVED_TEMP2);
// These registers must be preserved by runtime functions, otherwise
// we'd need to restore them here.
COMPILE_ASSERT(IsCalleeSavedRegister(THR));
COMPILE_ASSERT(IsCalleeSavedRegister(NULL_REG));
COMPILE_ASSERT(IsCalleeSavedRegister(WRITE_BARRIER_MASK));
COMPILE_ASSERT(IsCalleeSavedRegister(DISPATCH_TABLE_REG));
} else {
// Argument count is not checked here, but in the runtime entry for a more
// informative error message.
__ lx(T5, compiler::Address(THR, Thread::OffsetFromThread(runtime_entry)));
__ li(T4, argument_count);
__ JumpAndLinkToRuntime();
}
}
#endif // !defined(DART_PRECOMPILED_RUNTIME)
} // namespace dart
#endif // defined TARGET_ARCH_RISCV