* Move stub allocation inside the JITEmitter, instead of exposing a
way for each TargetJITInfo subclass to allocate its own stubs. This
means stubs aren't as exactly-sized anymore, but it lets us get rid of
TargetJITInfo::emitFunctionStubAtAddr(), which lets ARM and PPC
support the eager JIT, fixing http://llvm.org/PR4816.
* Rename the JITEmitter's stub creation functions to describe the kind
of stub they create. So far, all of them create lazy-compilation
stubs, but they sometimes get used when far-call stubs are needed.
Fixing http://llvm.org/PR5201 will involve fixing this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89715 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMJITInfo.cpp b/lib/Target/ARM/ARMJITInfo.cpp
index 7031640..aa50cfd 100644
--- a/lib/Target/ARM/ARMJITInfo.cpp
+++ b/lib/Target/ARM/ARMJITInfo.cpp
@@ -154,15 +154,22 @@
return PtrAddr;
}
+TargetJITInfo::StubLayout ARMJITInfo::getStubLayout() {
+ // The stub contains up to 3 4-byte instructions, aligned at 4 bytes, and a
+ // 4-byte address. See emitFunctionStub for details.
+ StubLayout Result = {16, 4};
+ return Result;
+}
+
void *ARMJITInfo::emitFunctionStub(const Function* F, void *Fn,
JITCodeEmitter &JCE) {
- MachineCodeEmitter::BufferState BS;
+ void *Addr;
// If this is just a call to an external function, emit a branch instead of a
// call. The code is the same except for one bit of the last instruction.
if (Fn != (void*)(intptr_t)ARMCompilationCallback) {
// Branch to the corresponding function addr.
if (IsPIC) {
- // The stub is 8-byte size and 4-aligned.
+ // The stub is 16-byte size and 4-aligned.
intptr_t LazyPtr = getIndirectSymAddr(Fn);
if (!LazyPtr) {
// In PIC mode, the function stub is loading a lazy-ptr.
@@ -174,30 +181,30 @@
errs() << "JIT: Stub emitted at [" << LazyPtr
<< "] for external function at '" << Fn << "'\n");
}
- JCE.startGVStub(BS, F, 16, 4);
- intptr_t Addr = (intptr_t)JCE.getCurrentPCValue();
- if (!sys::Memory::setRangeWritable((void*)Addr, 16)) {
+ JCE.emitAlignment(4);
+ Addr = (void*)JCE.getCurrentPCValue();
+ if (!sys::Memory::setRangeWritable(Addr, 16)) {
llvm_unreachable("ERROR: Unable to mark stub writable");
}
JCE.emitWordLE(0xe59fc004); // ldr ip, [pc, #+4]
JCE.emitWordLE(0xe08fc00c); // L_func$scv: add ip, pc, ip
JCE.emitWordLE(0xe59cf000); // ldr pc, [ip]
- JCE.emitWordLE(LazyPtr - (Addr+4+8)); // func - (L_func$scv+8)
- sys::Memory::InvalidateInstructionCache((void*)Addr, 16);
- if (!sys::Memory::setRangeExecutable((void*)Addr, 16)) {
+ JCE.emitWordLE(LazyPtr - (intptr_t(Addr)+4+8)); // func - (L_func$scv+8)
+ sys::Memory::InvalidateInstructionCache(Addr, 16);
+ if (!sys::Memory::setRangeExecutable(Addr, 16)) {
llvm_unreachable("ERROR: Unable to mark stub executable");
}
} else {
// The stub is 8-byte size and 4-aligned.
- JCE.startGVStub(BS, F, 8, 4);
- intptr_t Addr = (intptr_t)JCE.getCurrentPCValue();
- if (!sys::Memory::setRangeWritable((void*)Addr, 8)) {
+ JCE.emitAlignment(4);
+ Addr = (void*)JCE.getCurrentPCValue();
+ if (!sys::Memory::setRangeWritable(Addr, 8)) {
llvm_unreachable("ERROR: Unable to mark stub writable");
}
JCE.emitWordLE(0xe51ff004); // ldr pc, [pc, #-4]
JCE.emitWordLE((intptr_t)Fn); // addr of function
- sys::Memory::InvalidateInstructionCache((void*)Addr, 8);
- if (!sys::Memory::setRangeExecutable((void*)Addr, 8)) {
+ sys::Memory::InvalidateInstructionCache(Addr, 8);
+ if (!sys::Memory::setRangeExecutable(Addr, 8)) {
llvm_unreachable("ERROR: Unable to mark stub executable");
}
}
@@ -209,9 +216,9 @@
//
// Branch and link to the compilation callback.
// The stub is 16-byte size and 4-byte aligned.
- JCE.startGVStub(BS, F, 16, 4);
- intptr_t Addr = (intptr_t)JCE.getCurrentPCValue();
- if (!sys::Memory::setRangeWritable((void*)Addr, 16)) {
+ JCE.emitAlignment(4);
+ Addr = (void*)JCE.getCurrentPCValue();
+ if (!sys::Memory::setRangeWritable(Addr, 16)) {
llvm_unreachable("ERROR: Unable to mark stub writable");
}
// Save LR so the callback can determine which stub called it.
@@ -224,13 +231,13 @@
JCE.emitWordLE(0xe51ff004); // ldr pc, [pc, #-4]
// The address of the compilation callback.
JCE.emitWordLE((intptr_t)ARMCompilationCallback);
- sys::Memory::InvalidateInstructionCache((void*)Addr, 16);
- if (!sys::Memory::setRangeExecutable((void*)Addr, 16)) {
+ sys::Memory::InvalidateInstructionCache(Addr, 16);
+ if (!sys::Memory::setRangeExecutable(Addr, 16)) {
llvm_unreachable("ERROR: Unable to mark stub executable");
}
}
- return JCE.finishGVStub(BS);
+ return Addr;
}
intptr_t ARMJITInfo::resolveRelocDestAddr(MachineRelocation *MR) const {