llvm-6502/lib/Target/Sparc/SparcJITInfo.cpp

166 lines
5.2 KiB
C++

//===-- SparcJITInfo.cpp - Implement the Sparc JIT Interface --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the JIT interfaces for the Sparc target.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "jit"
#include "SparcJITInfo.h"
#include "SparcRelocations.h"
#include "llvm/CodeGen/JITCodeEmitter.h"
#include "llvm/Support/Memory.h"
using namespace llvm;
/// JITCompilerFunction - This contains the address of the JIT function used to
/// compile a function lazily.
static TargetJITInfo::JITCompilerFn JITCompilerFunction;
extern "C" void SparcCompilationCallback();
extern "C" {
#if defined (__sparc__)
asm(
".text\n"
"\t.align 4\n"
"\t.global SparcCompilationCallback\n"
"\t.type SparcCompilationCallback, #function\n"
"SparcCompilationCallback:\n"
// Save current register window.
"\tsave %sp, -192, %sp\n"
// stubaddr+4 is in %g1.
"\tcall SparcCompilationCallbackC\n"
"\t sub %g1, 4, %o0\n"
// restore original register window and
// copy %o0 to %g1
"\t restore %o0, 0, %g1\n"
// call the new stub
"\tjmp %g1\n"
"\t nop\n"
"\t.size SparcCompilationCallback, .-SparcCompilationCallback"
);
#else
void SparcCompilationCallback() {
llvm_unreachable(
"Cannot call SparcCompilationCallback() on a non-sparc arch!");
}
#endif
}
#define HI(Val) (((unsigned)(Val)) >> 10)
#define LO(Val) (((unsigned)(Val)) & 0x3FF)
#define SETHI_INST(imm, rd) (0x01000000 | ((rd) << 25) | ((imm) & 0x3FFFFF))
#define JMP_INST(rs1, imm, rd) (0x80000000 | ((rd) << 25) | (0x38 << 19) \
| ((rs1) << 14) | (1 << 13) | ((imm) & 0x1FFF))
#define NOP_INST SETHI_INST(0, 0)
extern "C" void *SparcCompilationCallbackC(intptr_t StubAddr) {
// Get the address of the compiled code for this function.
intptr_t NewVal = (intptr_t) JITCompilerFunction((void*) StubAddr);
// Rewrite the function stub so that we don't end up here every time we
// execute the call. We're replacing the first three instructions of the
// stub with code that jumps to the compiled function:
// sethi %hi(NewVal), %g1
// jmp %g1+%lo(NewVal)
// nop
*(intptr_t *)(StubAddr) = SETHI_INST(HI(NewVal), 1);
*(intptr_t *)(StubAddr + 4) = JMP_INST(1, LO(NewVal), 0);
*(intptr_t *)(StubAddr + 8) = NOP_INST;
sys::Memory::InvalidateInstructionCache((void*) StubAddr, 12);
return (void*)StubAddr;
}
void SparcJITInfo::replaceMachineCodeForFunction(void *Old, void *New) {
assert(0 && "FIXME: Implement SparcJITInfo::replaceMachineCodeForFunction");
}
TargetJITInfo::StubLayout SparcJITInfo::getStubLayout() {
// The stub contains 3 4-byte instructions, aligned at 4 bytes. See
// emitFunctionStub for details.
StubLayout Result = { 3*4, 4 };
return Result;
}
void *SparcJITInfo::emitFunctionStub(const Function *F, void *Fn,
JITCodeEmitter &JCE)
{
JCE.emitAlignment(4);
void *Addr = (void*) (JCE.getCurrentPCValue());
if (!sys::Memory::setRangeWritable(Addr, 12))
llvm_unreachable("ERROR: Unable to mark stub writable.");
intptr_t EmittedAddr;
if (Fn != (void*)(intptr_t)SparcCompilationCallback)
EmittedAddr = (intptr_t)Fn;
else
EmittedAddr = (intptr_t)SparcCompilationCallback;
// sethi %hi(EmittedAddr), %g1
// jmp %g1+%lo(EmittedAddr), %g1
// nop
JCE.emitWordBE(SETHI_INST(HI(EmittedAddr), 1));
JCE.emitWordBE(JMP_INST(1, LO(EmittedAddr), 1));
JCE.emitWordBE(NOP_INST);
sys::Memory::InvalidateInstructionCache(Addr, 12);
if (!sys::Memory::setRangeExecutable(Addr, 12))
llvm_unreachable("ERROR: Unable to mark stub executable.");
return Addr;
}
TargetJITInfo::LazyResolverFn
SparcJITInfo::getLazyResolverFunction(JITCompilerFn F) {
JITCompilerFunction = F;
return SparcCompilationCallback;
}
/// relocate - Before the JIT can run a block of code that has been emitted,
/// it must rewrite the code to contain the actual addresses of any
/// referenced global symbols.
void SparcJITInfo::relocate(void *Function, MachineRelocation *MR,
unsigned NumRelocs, unsigned char *GOTBase) {
for (unsigned i = 0; i != NumRelocs; ++i, ++MR) {
void *RelocPos = (char*) Function + MR->getMachineCodeOffset();
intptr_t ResultPtr = (intptr_t) MR->getResultPointer();
switch ((SP::RelocationType) MR->getRelocationType()) {
case SP::reloc_sparc_hi:
ResultPtr = (ResultPtr >> 10) & 0x3fffff;
break;
case SP::reloc_sparc_lo:
ResultPtr = (ResultPtr & 0x3ff);
break;
case SP::reloc_sparc_pc30:
ResultPtr = ((ResultPtr - (intptr_t)RelocPos) >> 2) & 0x3fffffff;
break;
case SP::reloc_sparc_pc22:
ResultPtr = ((ResultPtr - (intptr_t)RelocPos) >> 2) & 0x3fffff;
break;
case SP::reloc_sparc_pc19:
ResultPtr = ((ResultPtr - (intptr_t)RelocPos) >> 2) & 0x7ffff;
break;
}
*((unsigned*) RelocPos) |= (unsigned) ResultPtr;
}
}