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-rw-r--r--lib/ExecutionEngine/Interpreter/ExternalFunctions.cpp542
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diff --git a/lib/ExecutionEngine/Interpreter/ExternalFunctions.cpp b/lib/ExecutionEngine/Interpreter/ExternalFunctions.cpp
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+//===-- ExternalFunctions.cpp - Implement External Functions --------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains both code to deal with invoking "external" functions, but
+// also contains code that implements "exported" external functions.
+//
+// There are currently two mechanisms for handling external functions in the
+// Interpreter. The first is to implement lle_* wrapper functions that are
+// specific to well-known library functions which manually translate the
+// arguments from GenericValues and make the call. If such a wrapper does
+// not exist, and libffi is available, then the Interpreter will attempt to
+// invoke the function using libffi, after finding its address.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Interpreter.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Module.h"
+#include "llvm/Config/config.h" // Detect libffi
+#include "llvm/Support/Streams.h"
+#include "llvm/System/DynamicLibrary.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Support/ManagedStatic.h"
+#include <csignal>
+#include <cstdio>
+#include <map>
+#include <cmath>
+#include <cstring>
+
+#ifdef HAVE_FFI_CALL
+#ifdef HAVE_FFI_H
+#include <ffi.h>
+#define USE_LIBFFI
+#elif HAVE_FFI_FFI_H
+#include <ffi/ffi.h>
+#define USE_LIBFFI
+#endif
+#endif
+
+using namespace llvm;
+
+typedef GenericValue (*ExFunc)(const FunctionType *,
+ const std::vector<GenericValue> &);
+static ManagedStatic<std::map<const Function *, ExFunc> > ExportedFunctions;
+static std::map<std::string, ExFunc> FuncNames;
+
+#ifdef USE_LIBFFI
+typedef void (*RawFunc)(void);
+static ManagedStatic<std::map<const Function *, RawFunc> > RawFunctions;
+#endif
+
+static Interpreter *TheInterpreter;
+
+static char getTypeID(const Type *Ty) {
+ switch (Ty->getTypeID()) {
+ case Type::VoidTyID: return 'V';
+ case Type::IntegerTyID:
+ switch (cast<IntegerType>(Ty)->getBitWidth()) {
+ case 1: return 'o';
+ case 8: return 'B';
+ case 16: return 'S';
+ case 32: return 'I';
+ case 64: return 'L';
+ default: return 'N';
+ }
+ case Type::FloatTyID: return 'F';
+ case Type::DoubleTyID: return 'D';
+ case Type::PointerTyID: return 'P';
+ case Type::FunctionTyID:return 'M';
+ case Type::StructTyID: return 'T';
+ case Type::ArrayTyID: return 'A';
+ case Type::OpaqueTyID: return 'O';
+ default: return 'U';
+ }
+}
+
+// Try to find address of external function given a Function object.
+// Please note, that interpreter doesn't know how to assemble a
+// real call in general case (this is JIT job), that's why it assumes,
+// that all external functions has the same (and pretty "general") signature.
+// The typical example of such functions are "lle_X_" ones.
+static ExFunc lookupFunction(const Function *F) {
+ // Function not found, look it up... start by figuring out what the
+ // composite function name should be.
+ std::string ExtName = "lle_";
+ const FunctionType *FT = F->getFunctionType();
+ for (unsigned i = 0, e = FT->getNumContainedTypes(); i != e; ++i)
+ ExtName += getTypeID(FT->getContainedType(i));
+ ExtName += "_" + F->getName();
+
+ ExFunc FnPtr = FuncNames[ExtName];
+ if (FnPtr == 0)
+ FnPtr = FuncNames["lle_X_"+F->getName()];
+ if (FnPtr == 0) // Try calling a generic function... if it exists...
+ FnPtr = (ExFunc)(intptr_t)sys::DynamicLibrary::SearchForAddressOfSymbol(
+ ("lle_X_"+F->getName()).c_str());
+ if (FnPtr != 0)
+ ExportedFunctions->insert(std::make_pair(F, FnPtr)); // Cache for later
+ return FnPtr;
+}
+
+#ifdef USE_LIBFFI
+static ffi_type *ffiTypeFor(const Type *Ty) {
+ switch (Ty->getTypeID()) {
+ case Type::VoidTyID: return &ffi_type_void;
+ case Type::IntegerTyID:
+ switch (cast<IntegerType>(Ty)->getBitWidth()) {
+ case 8: return &ffi_type_sint8;
+ case 16: return &ffi_type_sint16;
+ case 32: return &ffi_type_sint32;
+ case 64: return &ffi_type_sint64;
+ }
+ case Type::FloatTyID: return &ffi_type_float;
+ case Type::DoubleTyID: return &ffi_type_double;
+ case Type::PointerTyID: return &ffi_type_pointer;
+ default: break;
+ }
+ // TODO: Support other types such as StructTyID, ArrayTyID, OpaqueTyID, etc.
+ cerr << "Type could not be mapped for use with libffi.\n";
+ abort();
+ return NULL;
+}
+
+static void *ffiValueFor(const Type *Ty, const GenericValue &AV,
+ void *ArgDataPtr) {
+ switch (Ty->getTypeID()) {
+ case Type::IntegerTyID:
+ switch (cast<IntegerType>(Ty)->getBitWidth()) {
+ case 8: {
+ int8_t *I8Ptr = (int8_t *) ArgDataPtr;
+ *I8Ptr = (int8_t) AV.IntVal.getZExtValue();
+ return ArgDataPtr;
+ }
+ case 16: {
+ int16_t *I16Ptr = (int16_t *) ArgDataPtr;
+ *I16Ptr = (int16_t) AV.IntVal.getZExtValue();
+ return ArgDataPtr;
+ }
+ case 32: {
+ int32_t *I32Ptr = (int32_t *) ArgDataPtr;
+ *I32Ptr = (int32_t) AV.IntVal.getZExtValue();
+ return ArgDataPtr;
+ }
+ case 64: {
+ int64_t *I64Ptr = (int64_t *) ArgDataPtr;
+ *I64Ptr = (int64_t) AV.IntVal.getZExtValue();
+ return ArgDataPtr;
+ }
+ }
+ case Type::FloatTyID: {
+ float *FloatPtr = (float *) ArgDataPtr;
+ *FloatPtr = AV.DoubleVal;
+ return ArgDataPtr;
+ }
+ case Type::DoubleTyID: {
+ double *DoublePtr = (double *) ArgDataPtr;
+ *DoublePtr = AV.DoubleVal;
+ return ArgDataPtr;
+ }
+ case Type::PointerTyID: {
+ void **PtrPtr = (void **) ArgDataPtr;
+ *PtrPtr = GVTOP(AV);
+ return ArgDataPtr;
+ }
+ default: break;
+ }
+ // TODO: Support other types such as StructTyID, ArrayTyID, OpaqueTyID, etc.
+ cerr << "Type value could not be mapped for use with libffi.\n";
+ abort();
+ return NULL;
+}
+
+static bool ffiInvoke(RawFunc Fn, Function *F,
+ const std::vector<GenericValue> &ArgVals,
+ const TargetData *TD, GenericValue &Result) {
+ ffi_cif cif;
+ const FunctionType *FTy = F->getFunctionType();
+ const unsigned NumArgs = F->arg_size();
+
+ // TODO: We don't have type information about the remaining arguments, because
+ // this information is never passed into ExecutionEngine::runFunction().
+ if (ArgVals.size() > NumArgs && F->isVarArg()) {
+ cerr << "Calling external var arg function '" << F->getName()
+ << "' is not supported by the Interpreter.\n";
+ abort();
+ }
+
+ unsigned ArgBytes = 0;
+
+ std::vector<ffi_type*> args(NumArgs);
+ for (Function::const_arg_iterator A = F->arg_begin(), E = F->arg_end();
+ A != E; ++A) {
+ const unsigned ArgNo = A->getArgNo();
+ const Type *ArgTy = FTy->getParamType(ArgNo);
+ args[ArgNo] = ffiTypeFor(ArgTy);
+ ArgBytes += TD->getTypeStoreSize(ArgTy);
+ }
+
+ uint8_t *ArgData = (uint8_t*) alloca(ArgBytes);
+ uint8_t *ArgDataPtr = ArgData;
+ std::vector<void*> values(NumArgs);
+ for (Function::const_arg_iterator A = F->arg_begin(), E = F->arg_end();
+ A != E; ++A) {
+ const unsigned ArgNo = A->getArgNo();
+ const Type *ArgTy = FTy->getParamType(ArgNo);
+ values[ArgNo] = ffiValueFor(ArgTy, ArgVals[ArgNo], ArgDataPtr);
+ ArgDataPtr += TD->getTypeStoreSize(ArgTy);
+ }
+
+ const Type *RetTy = FTy->getReturnType();
+ ffi_type *rtype = ffiTypeFor(RetTy);
+
+ if (ffi_prep_cif(&cif, FFI_DEFAULT_ABI, NumArgs, rtype, &args[0]) == FFI_OK) {
+ void *ret = NULL;
+ if (RetTy->getTypeID() != Type::VoidTyID)
+ ret = alloca(TD->getTypeStoreSize(RetTy));
+ ffi_call(&cif, Fn, ret, &values[0]);
+ switch (RetTy->getTypeID()) {
+ case Type::IntegerTyID:
+ switch (cast<IntegerType>(RetTy)->getBitWidth()) {
+ case 8: Result.IntVal = APInt(8 , *(int8_t *) ret); break;
+ case 16: Result.IntVal = APInt(16, *(int16_t*) ret); break;
+ case 32: Result.IntVal = APInt(32, *(int32_t*) ret); break;
+ case 64: Result.IntVal = APInt(64, *(int64_t*) ret); break;
+ }
+ break;
+ case Type::FloatTyID: Result.FloatVal = *(float *) ret; break;
+ case Type::DoubleTyID: Result.DoubleVal = *(double*) ret; break;
+ case Type::PointerTyID: Result.PointerVal = *(void **) ret; break;
+ default: break;
+ }
+ return true;
+ }
+
+ return false;
+}
+#endif // USE_LIBFFI
+
+GenericValue Interpreter::callExternalFunction(Function *F,
+ const std::vector<GenericValue> &ArgVals) {
+ TheInterpreter = this;
+
+ // Do a lookup to see if the function is in our cache... this should just be a
+ // deferred annotation!
+ std::map<const Function *, ExFunc>::iterator FI = ExportedFunctions->find(F);
+ if (ExFunc Fn = (FI == ExportedFunctions->end()) ? lookupFunction(F)
+ : FI->second)
+ return Fn(F->getFunctionType(), ArgVals);
+
+#ifdef USE_LIBFFI
+ std::map<const Function *, RawFunc>::iterator RF = RawFunctions->find(F);
+ RawFunc RawFn;
+ if (RF == RawFunctions->end()) {
+ RawFn = (RawFunc)(intptr_t)
+ sys::DynamicLibrary::SearchForAddressOfSymbol(F->getName());
+ if (RawFn != 0)
+ RawFunctions->insert(std::make_pair(F, RawFn)); // Cache for later
+ } else {
+ RawFn = RF->second;
+ }
+
+ GenericValue Result;
+ if (RawFn != 0 && ffiInvoke(RawFn, F, ArgVals, getTargetData(), Result))
+ return Result;
+#endif // USE_LIBFFI
+
+ cerr << "Tried to execute an unknown external function: "
+ << F->getType()->getDescription() << " " << F->getName() << "\n";
+ if (F->getName() != "__main")
+ abort();
+ return GenericValue();
+}
+
+
+//===----------------------------------------------------------------------===//
+// Functions "exported" to the running application...
+//
+extern "C" { // Don't add C++ manglings to llvm mangling :)
+
+// void atexit(Function*)
+GenericValue lle_X_atexit(const FunctionType *FT,
+ const std::vector<GenericValue> &Args) {
+ assert(Args.size() == 1);
+ TheInterpreter->addAtExitHandler((Function*)GVTOP(Args[0]));
+ GenericValue GV;
+ GV.IntVal = 0;
+ return GV;
+}
+
+// void exit(int)
+GenericValue lle_X_exit(const FunctionType *FT,
+ const std::vector<GenericValue> &Args) {
+ TheInterpreter->exitCalled(Args[0]);
+ return GenericValue();
+}
+
+// void abort(void)
+GenericValue lle_X_abort(const FunctionType *FT,
+ const std::vector<GenericValue> &Args) {
+ raise (SIGABRT);
+ return GenericValue();
+}
+
+// int sprintf(char *, const char *, ...) - a very rough implementation to make
+// output useful.
+GenericValue lle_X_sprintf(const FunctionType *FT,
+ const std::vector<GenericValue> &Args) {
+ char *OutputBuffer = (char *)GVTOP(Args[0]);
+ const char *FmtStr = (const char *)GVTOP(Args[1]);
+ unsigned ArgNo = 2;
+
+ // printf should return # chars printed. This is completely incorrect, but
+ // close enough for now.
+ GenericValue GV;
+ GV.IntVal = APInt(32, strlen(FmtStr));
+ while (1) {
+ switch (*FmtStr) {
+ case 0: return GV; // Null terminator...
+ default: // Normal nonspecial character
+ sprintf(OutputBuffer++, "%c", *FmtStr++);
+ break;
+ case '\\': { // Handle escape codes
+ sprintf(OutputBuffer, "%c%c", *FmtStr, *(FmtStr+1));
+ FmtStr += 2; OutputBuffer += 2;
+ break;
+ }
+ case '%': { // Handle format specifiers
+ char FmtBuf[100] = "", Buffer[1000] = "";
+ char *FB = FmtBuf;
+ *FB++ = *FmtStr++;
+ char Last = *FB++ = *FmtStr++;
+ unsigned HowLong = 0;
+ while (Last != 'c' && Last != 'd' && Last != 'i' && Last != 'u' &&
+ Last != 'o' && Last != 'x' && Last != 'X' && Last != 'e' &&
+ Last != 'E' && Last != 'g' && Last != 'G' && Last != 'f' &&
+ Last != 'p' && Last != 's' && Last != '%') {
+ if (Last == 'l' || Last == 'L') HowLong++; // Keep track of l's
+ Last = *FB++ = *FmtStr++;
+ }
+ *FB = 0;
+
+ switch (Last) {
+ case '%':
+ strcpy(Buffer, "%"); break;
+ case 'c':
+ sprintf(Buffer, FmtBuf, uint32_t(Args[ArgNo++].IntVal.getZExtValue()));
+ break;
+ case 'd': case 'i':
+ case 'u': case 'o':
+ case 'x': case 'X':
+ if (HowLong >= 1) {
+ if (HowLong == 1 &&
+ TheInterpreter->getTargetData()->getPointerSizeInBits() == 64 &&
+ sizeof(long) < sizeof(int64_t)) {
+ // Make sure we use %lld with a 64 bit argument because we might be
+ // compiling LLI on a 32 bit compiler.
+ unsigned Size = strlen(FmtBuf);
+ FmtBuf[Size] = FmtBuf[Size-1];
+ FmtBuf[Size+1] = 0;
+ FmtBuf[Size-1] = 'l';
+ }
+ sprintf(Buffer, FmtBuf, Args[ArgNo++].IntVal.getZExtValue());
+ } else
+ sprintf(Buffer, FmtBuf,uint32_t(Args[ArgNo++].IntVal.getZExtValue()));
+ break;
+ case 'e': case 'E': case 'g': case 'G': case 'f':
+ sprintf(Buffer, FmtBuf, Args[ArgNo++].DoubleVal); break;
+ case 'p':
+ sprintf(Buffer, FmtBuf, (void*)GVTOP(Args[ArgNo++])); break;
+ case 's':
+ sprintf(Buffer, FmtBuf, (char*)GVTOP(Args[ArgNo++])); break;
+ default: cerr << "<unknown printf code '" << *FmtStr << "'!>";
+ ArgNo++; break;
+ }
+ strcpy(OutputBuffer, Buffer);
+ OutputBuffer += strlen(Buffer);
+ }
+ break;
+ }
+ }
+ return GV;
+}
+
+// int printf(const char *, ...) - a very rough implementation to make output
+// useful.
+GenericValue lle_X_printf(const FunctionType *FT,
+ const std::vector<GenericValue> &Args) {
+ char Buffer[10000];
+ std::vector<GenericValue> NewArgs;
+ NewArgs.push_back(PTOGV((void*)&Buffer[0]));
+ NewArgs.insert(NewArgs.end(), Args.begin(), Args.end());
+ GenericValue GV = lle_X_sprintf(FT, NewArgs);
+ cout << Buffer;
+ return GV;
+}
+
+static void ByteswapSCANFResults(const char *Fmt, void *Arg0, void *Arg1,
+ void *Arg2, void *Arg3, void *Arg4, void *Arg5,
+ void *Arg6, void *Arg7, void *Arg8) {
+ void *Args[] = { Arg0, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7, Arg8, 0 };
+
+ // Loop over the format string, munging read values as appropriate (performs
+ // byteswaps as necessary).
+ unsigned ArgNo = 0;
+ while (*Fmt) {
+ if (*Fmt++ == '%') {
+ // Read any flag characters that may be present...
+ bool Suppress = false;
+ bool Half = false;
+ bool Long = false;
+ bool LongLong = false; // long long or long double
+
+ while (1) {
+ switch (*Fmt++) {
+ case '*': Suppress = true; break;
+ case 'a': /*Allocate = true;*/ break; // We don't need to track this
+ case 'h': Half = true; break;
+ case 'l': Long = true; break;
+ case 'q':
+ case 'L': LongLong = true; break;
+ default:
+ if (Fmt[-1] > '9' || Fmt[-1] < '0') // Ignore field width specs
+ goto Out;
+ }
+ }
+ Out:
+
+ // Read the conversion character
+ if (!Suppress && Fmt[-1] != '%') { // Nothing to do?
+ unsigned Size = 0;
+ const Type *Ty = 0;
+
+ switch (Fmt[-1]) {
+ case 'i': case 'o': case 'u': case 'x': case 'X': case 'n': case 'p':
+ case 'd':
+ if (Long || LongLong) {
+ Size = 8; Ty = Type::Int64Ty;
+ } else if (Half) {
+ Size = 4; Ty = Type::Int16Ty;
+ } else {
+ Size = 4; Ty = Type::Int32Ty;
+ }
+ break;
+
+ case 'e': case 'g': case 'E':
+ case 'f':
+ if (Long || LongLong) {
+ Size = 8; Ty = Type::DoubleTy;
+ } else {
+ Size = 4; Ty = Type::FloatTy;
+ }
+ break;
+
+ case 's': case 'c': case '[': // No byteswap needed
+ Size = 1;
+ Ty = Type::Int8Ty;
+ break;
+
+ default: break;
+ }
+
+ if (Size) {
+ GenericValue GV;
+ void *Arg = Args[ArgNo++];
+ memcpy(&GV, Arg, Size);
+ TheInterpreter->StoreValueToMemory(GV, (GenericValue*)Arg, Ty);
+ }
+ }
+ }
+ }
+}
+
+// int sscanf(const char *format, ...);
+GenericValue lle_X_sscanf(const FunctionType *FT,
+ const std::vector<GenericValue> &args) {
+ assert(args.size() < 10 && "Only handle up to 10 args to sscanf right now!");
+
+ char *Args[10];
+ for (unsigned i = 0; i < args.size(); ++i)
+ Args[i] = (char*)GVTOP(args[i]);
+
+ GenericValue GV;
+ GV.IntVal = APInt(32, sscanf(Args[0], Args[1], Args[2], Args[3], Args[4],
+ Args[5], Args[6], Args[7], Args[8], Args[9]));
+ ByteswapSCANFResults(Args[1], Args[2], Args[3], Args[4],
+ Args[5], Args[6], Args[7], Args[8], Args[9], 0);
+ return GV;
+}
+
+// int scanf(const char *format, ...);
+GenericValue lle_X_scanf(const FunctionType *FT,
+ const std::vector<GenericValue> &args) {
+ assert(args.size() < 10 && "Only handle up to 10 args to scanf right now!");
+
+ char *Args[10];
+ for (unsigned i = 0; i < args.size(); ++i)
+ Args[i] = (char*)GVTOP(args[i]);
+
+ GenericValue GV;
+ GV.IntVal = APInt(32, scanf( Args[0], Args[1], Args[2], Args[3], Args[4],
+ Args[5], Args[6], Args[7], Args[8], Args[9]));
+ ByteswapSCANFResults(Args[0], Args[1], Args[2], Args[3], Args[4],
+ Args[5], Args[6], Args[7], Args[8], Args[9]);
+ return GV;
+}
+
+// int fprintf(FILE *, const char *, ...) - a very rough implementation to make
+// output useful.
+GenericValue lle_X_fprintf(const FunctionType *FT,
+ const std::vector<GenericValue> &Args) {
+ assert(Args.size() >= 2);
+ char Buffer[10000];
+ std::vector<GenericValue> NewArgs;
+ NewArgs.push_back(PTOGV(Buffer));
+ NewArgs.insert(NewArgs.end(), Args.begin()+1, Args.end());
+ GenericValue GV = lle_X_sprintf(FT, NewArgs);
+
+ fputs(Buffer, (FILE *) GVTOP(Args[0]));
+ return GV;
+}
+
+} // End extern "C"
+
+
+void Interpreter::initializeExternalFunctions() {
+ FuncNames["lle_X_atexit"] = lle_X_atexit;
+ FuncNames["lle_X_exit"] = lle_X_exit;
+ FuncNames["lle_X_abort"] = lle_X_abort;
+
+ FuncNames["lle_X_printf"] = lle_X_printf;
+ FuncNames["lle_X_sprintf"] = lle_X_sprintf;
+ FuncNames["lle_X_sscanf"] = lle_X_sscanf;
+ FuncNames["lle_X_scanf"] = lle_X_scanf;
+ FuncNames["lle_X_fprintf"] = lle_X_fprintf;
+}
+
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