1e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao//===-- ARMJITInfo.cpp - Implement the JIT interfaces for the ARM target --===// 2e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 3e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// The LLVM Compiler Infrastructure 4e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 5e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// This file is distributed under the University of Illinois Open Source 6e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// License. See LICENSE.TXT for details. 7e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 8e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao//===----------------------------------------------------------------------===// 9e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 10e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// This file implements the JIT interfaces for the ARM target. 11e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 12e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao//===----------------------------------------------------------------------===// 13e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 14e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#define DEBUG_TYPE "jit" 15e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include "ARMJITInfo.h" 16acf2077ca497980a066e8e7bb81ceec0de82d5daCraig Topper#include "ARM.h" 17e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include "ARMConstantPoolValue.h" 18e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include "ARMRelocations.h" 19e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include "ARMSubtarget.h" 20e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include "llvm/CodeGen/JITCodeEmitter.h" 210b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Function.h" 22e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include "llvm/Support/Debug.h" 23e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include "llvm/Support/ErrorHandling.h" 243cc52ea33c0b96d1682f14fc45c45b57df0f39b6Michael J. Spencer#include "llvm/Support/Memory.h" 25d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/Support/raw_ostream.h" 26e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include <cstdlib> 27e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaousing namespace llvm; 28e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 29e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaovoid ARMJITInfo::replaceMachineCodeForFunction(void *Old, void *New) { 307abe37e4aee38cc79d91dd069a37d7e91d5bef53Shih-wei Liao report_fatal_error("ARMJITInfo::replaceMachineCodeForFunction"); 31e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 32e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 33e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// JITCompilerFunction - This contains the address of the JIT function used to 34e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// compile a function lazily. 35e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaostatic TargetJITInfo::JITCompilerFn JITCompilerFunction; 36e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 37e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// Get the ASMPREFIX for the current host. This is often '_'. 38e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#ifndef __USER_LABEL_PREFIX__ 39e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#define __USER_LABEL_PREFIX__ 40e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#endif 41e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#define GETASMPREFIX2(X) #X 42e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#define GETASMPREFIX(X) GETASMPREFIX2(X) 43e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#define ASMPREFIX GETASMPREFIX(__USER_LABEL_PREFIX__) 44e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 45e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// CompilationCallback stub - We can't use a C function with inline assembly in 46692df93de427356d3ab7bb0438a3c998f28186eaBob Wilson// it, because the prolog/epilog inserted by GCC won't work for us. (We need 47e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// to preserve more context and manipulate the stack directly). Instead, 48e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// write our own wrapper, which does things our way, so we have complete 49e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// control over register saving and restoring. 50e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaoextern "C" { 513aef70314b053a1df4f85ca4a6f3890d06ebbdd6Stephen Hines#if defined(__arm__) 52e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao void ARMCompilationCallback(); 53e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao asm( 54e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ".text\n" 55e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ".align 2\n" 56e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ".globl " ASMPREFIX "ARMCompilationCallback\n" 57e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ASMPREFIX "ARMCompilationCallback:\n" 58e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Save caller saved registers since they may contain stuff 59e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // for the real target function right now. We have to act as if this 60e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // whole compilation callback doesn't exist as far as the caller is 61e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // concerned, so we can't just preserve the callee saved regs. 62e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "stmdb sp!, {r0, r1, r2, r3, lr}\n" 63e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao#if (defined(__VFP_FP__) && !defined(__SOFTFP__)) 642bbb22b8ef571cc11e0c0bb0a0f13670b5ef5cffBob Wilson "vstmdb sp!, {d0, d1, d2, d3, d4, d5, d6, d7}\n" 65e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#endif 66e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The LR contains the address of the stub function on entry. 67e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // pass it as the argument to the C part of the callback 68e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "mov r0, lr\n" 69e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "sub sp, sp, #4\n" 70e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Call the C portion of the callback 71e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "bl " ASMPREFIX "ARMCompilationCallbackC\n" 72e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "add sp, sp, #4\n" 73e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Restoring the LR to the return address of the function that invoked 74e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // the stub and de-allocating the stack space for it requires us to 75e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // swap the two saved LR values on the stack, as they're backwards 76e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // for what we need since the pop instruction has a pre-determined 77e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // order for the registers. 78e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // +--------+ 79e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 0 | LR | Original return address 80e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // +--------+ 81e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 1 | LR | Stub address (start of stub) 82e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 2-5 | R3..R0 | Saved registers (we need to preserve all regs) 83e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 6-20 | D0..D7 | Saved VFP registers 84e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // +--------+ 85e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 86e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao#if (defined(__VFP_FP__) && !defined(__SOFTFP__)) 87e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Restore VFP caller-saved registers. 882bbb22b8ef571cc11e0c0bb0a0f13670b5ef5cffBob Wilson "vldmia sp!, {d0, d1, d2, d3, d4, d5, d6, d7}\n" 89e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#endif 90e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 91e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // We need to exchange the values in slots 0 and 1 so we can 92e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // return to the address in slot 1 with the address in slot 0 93e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // restored to the LR. 94e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "ldr r0, [sp,#20]\n" 95e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "ldr r1, [sp,#16]\n" 96e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "str r1, [sp,#20]\n" 97e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "str r0, [sp,#16]\n" 98e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Return to the (newly modified) stub to invoke the real function. 99e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The above twiddling of the saved return addresses allows us to 10092e7195e433435eeb93d5f88de146878b76abb21Bob Wilson // deallocate everything, including the LR the stub saved, with two 10192e7195e433435eeb93d5f88de146878b76abb21Bob Wilson // updating load instructions. 102692df93de427356d3ab7bb0438a3c998f28186eaBob Wilson "ldmia sp!, {r0, r1, r2, r3, lr}\n" 103692df93de427356d3ab7bb0438a3c998f28186eaBob Wilson "ldr pc, [sp], #4\n" 104e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ); 105e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#else // Not an ARM host 106e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao void ARMCompilationCallback() { 107e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("Cannot call ARMCompilationCallback() on a non-ARM arch!"); 108e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 109e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#endif 110e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 111e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 112e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// ARMCompilationCallbackC - This is the target-specific function invoked 113e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// by the function stub when we did not know the real target of a call. 114e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// This function must locate the start of the stub or call site and pass 115e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// it into the JIT compiler function. 116e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaoextern "C" void ARMCompilationCallbackC(intptr_t StubAddr) { 117e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Get the address of the compiled code for this function. 118e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao intptr_t NewVal = (intptr_t)JITCompilerFunction((void*)StubAddr); 119e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 120e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Rewrite the call target... so that we don't end up here every time we 121e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // execute the call. We're replacing the first two instructions of the 122e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // stub with: 123e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // ldr pc, [pc,#-4] 124e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // <addr> 125e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeWritable((void*)StubAddr, 8)) { 126e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub writable"); 127e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 128e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *(intptr_t *)StubAddr = 0xe51ff004; // ldr pc, [pc, #-4] 129e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *(intptr_t *)(StubAddr+4) = NewVal; 130e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeExecutable((void*)StubAddr, 8)) { 131e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub executable"); 132e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 133e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 134e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 135e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei LiaoTargetJITInfo::LazyResolverFn 136e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei LiaoARMJITInfo::getLazyResolverFunction(JITCompilerFn F) { 137e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JITCompilerFunction = F; 138e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return ARMCompilationCallback; 139e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 140e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 141e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaovoid *ARMJITInfo::emitGlobalValueIndirectSym(const GlobalValue *GV, void *Ptr, 142e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JITCodeEmitter &JCE) { 143e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao uint8_t Buffer[4]; 144e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao uint8_t *Cur = Buffer; 145e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao MachineCodeEmitter::emitWordLEInto(Cur, (intptr_t)Ptr); 146e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao void *PtrAddr = JCE.allocIndirectGV( 147e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao GV, Buffer, sizeof(Buffer), /*Alignment=*/4); 148e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao addIndirectSymAddr(Ptr, (intptr_t)PtrAddr); 149e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return PtrAddr; 150e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 151e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 152e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei LiaoTargetJITInfo::StubLayout ARMJITInfo::getStubLayout() { 153e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The stub contains up to 3 4-byte instructions, aligned at 4 bytes, and a 154e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 4-byte address. See emitFunctionStub for details. 155e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao StubLayout Result = {16, 4}; 156e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return Result; 157e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 158e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 159e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaovoid *ARMJITInfo::emitFunctionStub(const Function* F, void *Fn, 160e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JITCodeEmitter &JCE) { 161e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao void *Addr; 162e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // If this is just a call to an external function, emit a branch instead of a 163e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // call. The code is the same except for one bit of the last instruction. 164e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (Fn != (void*)(intptr_t)ARMCompilationCallback) { 165e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Branch to the corresponding function addr. 166e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (IsPIC) { 167e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The stub is 16-byte size and 4-aligned. 168e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao intptr_t LazyPtr = getIndirectSymAddr(Fn); 169e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!LazyPtr) { 170e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // In PIC mode, the function stub is loading a lazy-ptr. 17159324297650c12a8dccf1a7ad650a9e895fdc17eRoman Divacky LazyPtr= (intptr_t)emitGlobalValueIndirectSym((const GlobalValue*)F, Fn, JCE); 172e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao DEBUG(if (F) 173e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao errs() << "JIT: Indirect symbol emitted at [" << LazyPtr 174e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao << "] for GV '" << F->getName() << "'\n"; 175e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao else 176e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao errs() << "JIT: Stub emitted at [" << LazyPtr 177e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao << "] for external function at '" << Fn << "'\n"); 178e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 179e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitAlignment(4); 180e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Addr = (void*)JCE.getCurrentPCValue(); 181e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeWritable(Addr, 16)) { 182e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub writable"); 183e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 184e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(0xe59fc004); // ldr ip, [pc, #+4] 185e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(0xe08fc00c); // L_func$scv: add ip, pc, ip 186e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(0xe59cf000); // ldr pc, [ip] 187e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(LazyPtr - (intptr_t(Addr)+4+8)); // func - (L_func$scv+8) 188e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao sys::Memory::InvalidateInstructionCache(Addr, 16); 189e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeExecutable(Addr, 16)) { 190e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub executable"); 191e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 192e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } else { 193e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The stub is 8-byte size and 4-aligned. 194e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitAlignment(4); 195e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Addr = (void*)JCE.getCurrentPCValue(); 196e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeWritable(Addr, 8)) { 197e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub writable"); 198e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 199e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(0xe51ff004); // ldr pc, [pc, #-4] 200e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE((intptr_t)Fn); // addr of function 201e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao sys::Memory::InvalidateInstructionCache(Addr, 8); 202e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeExecutable(Addr, 8)) { 203e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub executable"); 204e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 205e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 206e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } else { 207e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The compilation callback will overwrite the first two words of this 208e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // stub with indirect branch instructions targeting the compiled code. 209e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // This stub sets the return address to restart the stub, so that 210e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // the new branch will be invoked when we come back. 211e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 212e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Branch and link to the compilation callback. 213e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The stub is 16-byte size and 4-byte aligned. 214e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitAlignment(4); 215e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Addr = (void*)JCE.getCurrentPCValue(); 216e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeWritable(Addr, 16)) { 217e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub writable"); 218e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 219e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Save LR so the callback can determine which stub called it. 220e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The compilation callback is responsible for popping this prior 221e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // to returning. 222e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(0xe92d4000); // push {lr} 223e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Set the return address to go back to the start of this stub. 224e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(0xe24fe00c); // sub lr, pc, #12 225e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Invoke the compilation callback. 226e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE(0xe51ff004); // ldr pc, [pc, #-4] 227e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // The address of the compilation callback. 228e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao JCE.emitWordLE((intptr_t)ARMCompilationCallback); 229e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao sys::Memory::InvalidateInstructionCache(Addr, 16); 230e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (!sys::Memory::setRangeExecutable(Addr, 16)) { 231e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao llvm_unreachable("ERROR: Unable to mark stub executable"); 232e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 233e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 234e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 235e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return Addr; 236e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 237e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 238e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaointptr_t ARMJITInfo::resolveRelocDestAddr(MachineRelocation *MR) const { 239e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ARM::RelocationType RT = (ARM::RelocationType)MR->getRelocationType(); 240e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao switch (RT) { 241e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao default: 242e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return (intptr_t)(MR->getResultPointer()); 243e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_pic_jt: 244e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Destination address - jump table base. 245e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return (intptr_t)(MR->getResultPointer()) - MR->getConstantVal(); 246e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_jt_base: 247e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Jump table base address. 248e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return getJumpTableBaseAddr(MR->getJumpTableIndex()); 249e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_cp_entry: 250e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_vfp_cp_entry: 251e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Constant pool entry address. 252e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return getConstantPoolEntryAddr(MR->getConstantPoolIndex()); 253e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_machine_cp_entry: { 254e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ARMConstantPoolValue *ACPV = (ARMConstantPoolValue*)MR->getConstantVal(); 255e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao assert((!ACPV->hasModifier() && !ACPV->mustAddCurrentAddress()) && 256e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao "Can't handle this machine constant pool entry yet!"); 257e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao intptr_t Addr = (intptr_t)(MR->getResultPointer()); 258e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Addr -= getPCLabelAddr(ACPV->getLabelId()) + ACPV->getPCAdjustment(); 259e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return Addr; 260e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 261e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 262e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 263e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 264e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// relocate - Before the JIT can run a block of code that has been emitted, 265e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// it must rewrite the code to contain the actual addresses of any 266e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// referenced global symbols. 267e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaovoid ARMJITInfo::relocate(void *Function, MachineRelocation *MR, 268e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao unsigned NumRelocs, unsigned char* GOTBase) { 269e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao for (unsigned i = 0; i != NumRelocs; ++i, ++MR) { 270e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao void *RelocPos = (char*)Function + MR->getMachineCodeOffset(); 271e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao intptr_t ResultPtr = resolveRelocDestAddr(MR); 272e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao switch ((ARM::RelocationType)MR->getRelocationType()) { 273e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_cp_entry: 274e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_vfp_cp_entry: 275e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_relative: { 276e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // It is necessary to calculate the correct PC relative value. We 277e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // subtract the base addr from the target addr to form a byte offset. 278e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ResultPtr = ResultPtr - (intptr_t)RelocPos - 8; 279e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // If the result is positive, set bit U(23) to 1. 280e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (ResultPtr >= 0) 281e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *((intptr_t*)RelocPos) |= 1 << ARMII::U_BitShift; 282e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao else { 283e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Otherwise, obtain the absolute value and set bit U(23) to 0. 284e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *((intptr_t*)RelocPos) &= ~(1 << ARMII::U_BitShift); 285e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ResultPtr = - ResultPtr; 286e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 287e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Set the immed value calculated. 288e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // VFP immediate offset is multiplied by 4. 289e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (MR->getRelocationType() == ARM::reloc_arm_vfp_cp_entry) 290e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ResultPtr = ResultPtr >> 2; 291e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *((intptr_t*)RelocPos) |= ResultPtr; 292df1c637ac4b6f6587c037be55cafed665c732d8fEric Christopher // Set register Rn to PC (which is register 15 on all architectures). 293df1c637ac4b6f6587c037be55cafed665c732d8fEric Christopher // FIXME: This avoids the need for register info in the JIT class. 294df1c637ac4b6f6587c037be55cafed665c732d8fEric Christopher *((intptr_t*)RelocPos) |= 15 << ARMII::RegRnShift; 295e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao break; 296e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 297e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_pic_jt: 298e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_machine_cp_entry: 299e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_absolute: { 300e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // These addresses have already been resolved. 301e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *((intptr_t*)RelocPos) |= (intptr_t)ResultPtr; 302e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao break; 303e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 304e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_branch: { 305e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // It is necessary to calculate the correct value of signed_immed_24 306e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // field. We subtract the base addr from the target addr to form a 307e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // byte offset, which must be inside the range -33554432 and +33554428. 308e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Then, we set the signed_immed_24 field of the instruction to bits 309e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // [25:2] of the byte offset. More details ARM-ARM p. A4-11. 310e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ResultPtr = ResultPtr - (intptr_t)RelocPos - 8; 311e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ResultPtr = (ResultPtr & 0x03FFFFFC) >> 2; 312e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao assert(ResultPtr >= -33554432 && ResultPtr <= 33554428); 313e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *((intptr_t*)RelocPos) |= ResultPtr; 314e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao break; 315e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 316e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao case ARM::reloc_arm_jt_base: { 317e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // JT base - (instruction addr + 8) 318e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao ResultPtr = ResultPtr - (intptr_t)RelocPos - 8; 319e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao *((intptr_t*)RelocPos) |= ResultPtr; 320e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao break; 321e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 322e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao case ARM::reloc_arm_movw: { 3235d392dd93e023f9c14353ea84e2db717792db4bdZonr Chang ResultPtr = ResultPtr & 0xFFFF; 324e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao *((intptr_t*)RelocPos) |= ResultPtr & 0xFFF; 3255d392dd93e023f9c14353ea84e2db717792db4bdZonr Chang *((intptr_t*)RelocPos) |= ((ResultPtr >> 12) & 0xF) << 16; 326e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao break; 327e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao } 328e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao case ARM::reloc_arm_movt: { 3295d392dd93e023f9c14353ea84e2db717792db4bdZonr Chang ResultPtr = (ResultPtr >> 16) & 0xFFFF; 330e4454320b3cfffe926a487c33fbeb454366de2f8Shih-wei Liao *((intptr_t*)RelocPos) |= ResultPtr & 0xFFF; 3315d392dd93e023f9c14353ea84e2db717792db4bdZonr Chang *((intptr_t*)RelocPos) |= ((ResultPtr >> 12) & 0xF) << 16; 3327f80b0a9af7a6618516fb29324c83b26189a7372Shih-wei Liao break; 3337f80b0a9af7a6618516fb29324c83b26189a7372Shih-wei Liao } 334e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 335e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 336e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} 337