mirror of
https://github.com/dart-lang/sdk
synced 2024-09-05 08:24:39 +00:00
[vm/ffi] Document shadow space and restore RSP
Split off from https://dart-review.googlesource.com/c/sdk/+/140290. We start using the stack after the C call, so RSP needs to be restored. Issue https://github.com/dart-lang/sdk/issues/36730. TEST=All existing FFI tests on windows. Change-Id: Idcaff9007c1b6f42b95288e39470b3d6cca2ef56 Cq-Include-Trybots: luci.dart.try:vm-kernel-win-debug-x64-try Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/170425 Reviewed-by: Martin Kustermann <kustermann@google.com> Commit-Queue: Daco Harkes <dacoharkes@google.com>
This commit is contained in:
parent
b1946a51ed
commit
633c5389a5
|
@ -1671,19 +1671,27 @@ void Assembler::LeaveCallRuntimeFrame() {
|
|||
LeaveStubFrame();
|
||||
}
|
||||
|
||||
void Assembler::CallCFunction(Register reg) {
|
||||
void Assembler::CallCFunction(Register reg, bool restore_rsp) {
|
||||
// Reserve shadow space for outgoing arguments.
|
||||
if (CallingConventions::kShadowSpaceBytes != 0) {
|
||||
subq(RSP, Immediate(CallingConventions::kShadowSpaceBytes));
|
||||
}
|
||||
call(reg);
|
||||
// Restore stack.
|
||||
if (restore_rsp && CallingConventions::kShadowSpaceBytes != 0) {
|
||||
addq(RSP, Immediate(CallingConventions::kShadowSpaceBytes));
|
||||
}
|
||||
}
|
||||
void Assembler::CallCFunction(Address address) {
|
||||
void Assembler::CallCFunction(Address address, bool restore_rsp) {
|
||||
// Reserve shadow space for outgoing arguments.
|
||||
if (CallingConventions::kShadowSpaceBytes != 0) {
|
||||
subq(RSP, Immediate(CallingConventions::kShadowSpaceBytes));
|
||||
}
|
||||
call(address);
|
||||
// Restore stack.
|
||||
if (restore_rsp && CallingConventions::kShadowSpaceBytes != 0) {
|
||||
addq(RSP, Immediate(CallingConventions::kShadowSpaceBytes));
|
||||
}
|
||||
}
|
||||
|
||||
void Assembler::CallRuntime(const RuntimeEntry& entry,
|
||||
|
|
|
@ -829,9 +829,9 @@ class Assembler : public AssemblerBase {
|
|||
void CallRuntime(const RuntimeEntry& entry, intptr_t argument_count);
|
||||
|
||||
// Call runtime function. Reserves shadow space on the stack before calling
|
||||
// if platform ABI requires that. Does not restore RSP after the call itself.
|
||||
void CallCFunction(Register reg);
|
||||
void CallCFunction(Address address);
|
||||
// if platform ABI requires that.
|
||||
void CallCFunction(Register reg, bool restore_rsp = false);
|
||||
void CallCFunction(Address address, bool restore_rsp = false);
|
||||
|
||||
void ExtractClassIdFromTags(Register result, Register tags);
|
||||
void ExtractInstanceSizeFromTags(Register result, Register tags);
|
||||
|
|
|
@ -1082,7 +1082,7 @@ void FfiCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
|
|||
__ TransitionGeneratedToNative(target_address, FPREG, TMP,
|
||||
/*enter_safepoint=*/true);
|
||||
|
||||
__ CallCFunction(target_address);
|
||||
__ CallCFunction(target_address, /*restore_rsp=*/true);
|
||||
|
||||
// Update information in the thread object and leave the safepoint.
|
||||
__ TransitionNativeToGenerated(/*leave_safepoint=*/true);
|
||||
|
|
|
@ -282,7 +282,7 @@ void StubCodeCompiler::GenerateCallNativeThroughSafepointStub(
|
|||
/*enter_safepoint=*/true);
|
||||
|
||||
__ popq(R12);
|
||||
__ CallCFunction(RBX);
|
||||
__ CallCFunction(RBX, /*restore_rsp=*/true);
|
||||
|
||||
__ TransitionNativeToGenerated(/*leave_safepoint=*/true);
|
||||
|
||||
|
|
|
@ -304,6 +304,16 @@ class CallingConventions {
|
|||
// same time? (Windows no, rest yes)
|
||||
static const bool kArgumentIntRegXorFpuReg = true;
|
||||
|
||||
// > The x64 Application Binary Interface (ABI) uses a four-register
|
||||
// > fast-call calling convention by default. Space is allocated on the call
|
||||
// > stack as a shadow store for callees to save those registers.
|
||||
// https://docs.microsoft.com/en-us/cpp/build/x64-calling-convention?view=msvc-160
|
||||
//
|
||||
// The caller allocates this space. The caller should also reclaim this space
|
||||
// after the call to restore the stack to its original state if needed.
|
||||
//
|
||||
// This is also known as home space.
|
||||
// https://devblogs.microsoft.com/oldnewthing/20160623-00/?p=93735
|
||||
static const intptr_t kShadowSpaceBytes = 4 * kWordSize;
|
||||
|
||||
static const intptr_t kVolatileCpuRegisters =
|
||||
|
|
Loading…
Reference in a new issue