Mercurial > projects > ldc
view gen/naked.cpp @ 1168:ab186e535e72
A different fix to #218 and DMD2682 that does not lead to constant folding regressions.
Fixes run/const_15, run/c/const_16_B.
The price is removing the lvalueness of struct literals. If it turns out too
much code depends on this behavior or we don't want to break with DMD, we
could keep struct literals as lvalues and instead convert struct literals used
as expression initializers into struct initializers.
author | Christian Kamm <kamm incasoftware de> |
---|---|
date | Sun, 29 Mar 2009 11:43:45 +0200 |
parents | 9279a9dc6df3 |
children | 204197eb9eb5 |
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#include "gen/llvm.h" #include "llvm/InlineAsm.h" #include "expression.h" #include "statement.h" #include "declaration.h" #include "template.h" #include <cassert> #include "gen/logger.h" #include "gen/irstate.h" #include "gen/llvmhelpers.h" #include "gen/tollvm.h" #include "gen/dvalue.h" ////////////////////////////////////////////////////////////////////////////////////////// void Statement::toNakedIR(IRState *p) { error("not allowed in naked function"); } ////////////////////////////////////////////////////////////////////////////////////////// void CompoundStatement::toNakedIR(IRState *p) { Logger::println("CompoundStatement::toNakedIR(): %s", loc.toChars()); LOG_SCOPE; if (statements) for (unsigned i = 0; i < statements->dim; i++) { Statement* s = (Statement*)statements->data[i]; if (s) s->toNakedIR(p); } } ////////////////////////////////////////////////////////////////////////////////////////// void ExpStatement::toNakedIR(IRState *p) { Logger::println("ExpStatement::toNakedIR(): %s", loc.toChars()); LOG_SCOPE; // only expstmt supported in declarations if (exp->op != TOKdeclaration) { Statement::toNakedIR(p); return; } DeclarationExp* d = (DeclarationExp*)exp; VarDeclaration* vd = d->declaration->isVarDeclaration(); FuncDeclaration* fd = d->declaration->isFuncDeclaration(); EnumDeclaration* ed = d->declaration->isEnumDeclaration(); // and only static variable/function declaration // no locals or nested stuffies! if (!vd && !fd && !ed) { Statement::toNakedIR(p); return; } else if (vd && !vd->isDataseg()) { error("non-static variable '%s' not allowed in naked function", vd->toChars()); return; } else if (fd && !fd->isStatic()) { error("non-static nested function '%s' not allowed in naked function", fd->toChars()); return; } // enum decls should always be safe // make sure the symbols gets processed d->declaration->codegen(Type::sir); } ////////////////////////////////////////////////////////////////////////////////////////// void LabelStatement::toNakedIR(IRState *p) { Logger::println("LabelStatement::toNakedIR(): %s", loc.toChars()); LOG_SCOPE; p->nakedAsm << p->func()->decl->mangle() << "_" << ident->toChars() << ":"; if (statement) statement->toNakedIR(p); } ////////////////////////////////////////////////////////////////////////////////////////// void DtoDefineNakedFunction(FuncDeclaration* fd) { Logger::println("DtoDefineNakedFunction(%s)", fd->mangle()); LOG_SCOPE; assert(fd->ir.irFunc); gIR->functions.push_back(fd->ir.irFunc); // we need to do special processing on the body, since we only want // to allow actual inline asm blocks to reach the final asm output std::ostringstream& asmstr = gIR->nakedAsm; // build function header // FIXME: could we perhaps use llvm asmwriter to give us these details ? const char* mangle = fd->mangle(); std::ostringstream tmpstr; // osx is different // also mangling has an extra underscore prefixed if (global.params.os == OSMacOSX) { std::string section = "text"; bool weak = false; if (DtoIsTemplateInstance(fd)) { tmpstr << "section\t__TEXT,__textcoal_nt,coalesced,pure_instructions"; section = tmpstr.str(); weak = true; } asmstr << "\t." << section << std::endl; asmstr << "\t.align\t4,0x90" << std::endl; asmstr << "\t.globl\t_" << mangle << std::endl; if (weak) { asmstr << "\t.weak_definition\t_" << mangle << std::endl; } asmstr << "_" << mangle << ":" << std::endl; } // this works on linux x86 32 and 64 bit // assume it works everywhere else as well for now else { const char* linkage = "globl"; std::string section = "text"; if (DtoIsTemplateInstance(fd)) { linkage = "weak"; tmpstr << "section\t.gnu.linkonce.t." << mangle << ",\"ax\",@progbits"; section = tmpstr.str(); } asmstr << "\t." << section << std::endl; asmstr << "\t.align\t16" << std::endl; asmstr << "\t." << linkage << "\t" << mangle << std::endl; asmstr << "\t.type\t" << mangle << ",@function" << std::endl; asmstr << mangle << ":" << std::endl; } // emit body fd->fbody->toNakedIR(gIR); // emit size after body // llvm does this on linux, but not on osx if (global.params.os != OSMacOSX) { asmstr << "\t.size\t" << mangle << ", .-" << mangle << std::endl << std::endl; } gIR->module->appendModuleInlineAsm(asmstr.str()); asmstr.str(""); gIR->functions.pop_back(); } ////////////////////////////////////////////////////////////////////////////////////////// void emitABIReturnAsmStmt(IRAsmBlock* asmblock, Loc loc, FuncDeclaration* fdecl) { Logger::println("emitABIReturnAsmStmt(%s)", fdecl->mangle()); LOG_SCOPE; IRAsmStmt* as = new IRAsmStmt; const LLType* llretTy = DtoType(fdecl->type->nextOf()); asmblock->retty = llretTy; asmblock->retn = 1; // FIXME: This should probably be handled by the TargetABI somehow. // It should be able to do this for a greater variety of types. // x86 if (global.params.cpu == ARCHx86) { LINK l = fdecl->linkage; assert((l == LINKd || l == LINKc || l == LINKwindows) && "invalid linkage for asm implicit return"); Type* rt = fdecl->type->nextOf()->toBasetype(); if (rt->isintegral() || rt->ty == Tpointer || rt->ty == Tclass || rt->ty == Taarray) { if (rt->size() == 8) { as->out_c = "=A,"; } else { as->out_c = "={ax},"; } } else if (rt->isfloating()) { if (rt->iscomplex()) { if (fdecl->linkage == LINKd) { // extern(D) always returns on the FPU stack as->out_c = "={st},={st(1)},"; asmblock->retn = 2; } else if (rt->ty == Tcomplex32) { // extern(C) cfloat is return as i64 as->out_c = "=A,"; asmblock->retty = LLType::Int64Ty; } else { // cdouble and creal extern(C) are returned in pointer // don't add anything! asmblock->retty = LLType::VoidTy; asmblock->retn = 0; return; } } else { as->out_c = "={st},"; } } else if (rt->ty == Tarray || rt->ty == Tdelegate) { as->out_c = "={ax},={dx},"; asmblock->retn = 2; #if 0 // this is to show how to allocate a temporary for the return value // in case the appropriate multi register constraint isn't supported. // this way abi return from inline asm can still be emulated. // note that "$<<out0>>" etc in the asm will translate to the correct // numbered output when the asm block in finalized // generate asm as->out_c = "=*m,=*m,"; LLValue* tmp = DtoAlloca(llretTy, ".tmp_asm_ret"); as->out.push_back( tmp ); as->out.push_back( DtoGEPi(tmp, 0,1) ); as->code = "movd %eax, $<<out0>>" "\n\t" "mov %edx, $<<out1>>"; // fix asmblock asmblock->retn = 0; asmblock->retemu = true; asmblock->asmBlock->abiret = tmp; // add "ret" stmt at the end of the block asmblock->s.push_back(as); // done, we don't want anything pushed in the front of the block return; #endif } else { error(loc, "unimplemented return type '%s' for implicit abi return", rt->toChars()); fatal(); } } // x86_64 else if (global.params.cpu == ARCHx86_64) { LINK l = fdecl->linkage; /* TODO: Check if this works with extern(Windows), completely untested. * In particular, returning cdouble may not work with * extern(Windows) since according to X86CallingConv.td it * doesn't allow XMM1 to be used. * (So is extern(C), but that should be fine as the calling convention * is identical to that of extern(D)) */ assert((l == LINKd || l == LINKc || l == LINKwindows) && "invalid linkage for asm implicit return"); Type* rt = fdecl->type->nextOf()->toBasetype(); if (rt->isintegral() || rt->ty == Tpointer || rt->ty == Tclass || rt->ty == Taarray) { as->out_c = "={ax},"; } else if (rt->isfloating()) { if (rt == Type::tcomplex80) { // On x87 stack, re=st, im=st(1) as->out_c = "={st},={st(1)},"; asmblock->retn = 2; } else if (rt == Type::tfloat80 || rt == Type::timaginary80) { // On x87 stack as->out_c = "={st},"; } else if (l != LINKd && rt == Type::tcomplex32) { // LLVM and GCC disagree on how to return {float, float}. // For compatibility, use the GCC/LLVM-GCC way for extern(C/Windows) // extern(C) cfloat -> %xmm0 (extract two floats) as->out_c = "={xmm0},"; asmblock->retty = LLType::DoubleTy; } else if (rt->iscomplex()) { // cdouble and extern(D) cfloat -> re=%xmm0, im=%xmm1 as->out_c = "={xmm0},={xmm1},"; asmblock->retn = 2; } else { // Plain float/double/ifloat/idouble as->out_c = "={xmm0},"; } } else if (rt->ty == Tarray || rt->ty == Tdelegate) { as->out_c = "={ax},={dx},"; asmblock->retn = 2; } else { error(loc, "unimplemented return type '%s' for implicit abi return", rt->toChars()); fatal(); } } // unsupported else { error(loc, "this target (%s) does not implement inline asm falling off the end of the function", global.params.targetTriple); fatal(); } // return values always go in the front asmblock->s.push_front(as); } ////////////////////////////////////////////////////////////////////////////////////////// // sort of kinda related to naked ... DValue * DtoInlineAsmExpr(Loc loc, FuncDeclaration * fd, Expressions * arguments) { Logger::println("DtoInlineAsmExpr @ %s", loc.toChars()); LOG_SCOPE; TemplateInstance* ti = fd->toParent()->isTemplateInstance(); assert(ti && "invalid inline __asm expr"); assert(arguments->dim >= 2 && "invalid __asm call"); // get code param Expression* e = (Expression*)arguments->data[0]; Logger::println("code exp: %s", e->toChars()); StringExp* se = (StringExp*)e; if (e->op != TOKstring || se->sz != 1) { e->error("__asm code argument is not a char[] string literal"); fatal(); } std::string code((char*)se->string, se->len); // get constraints param e = (Expression*)arguments->data[1]; Logger::println("constraint exp: %s", e->toChars()); se = (StringExp*)e; if (e->op != TOKstring || se->sz != 1) { e->error("__asm constraints argument is not a char[] string literal"); fatal(); } std::string constraints((char*)se->string, se->len); // build runtime arguments size_t n = arguments->dim; LLSmallVector<llvm::Value*, 8> args; args.reserve(n-2); std::vector<const llvm::Type*> argtypes; argtypes.reserve(n-2); for (size_t i = 2; i < n; i++) { e = (Expression*)arguments->data[i]; args.push_back(e->toElem(gIR)->getRVal()); argtypes.push_back(args.back()->getType()); } // build asm function type Type* type = fd->type->nextOf()->toBasetype(); const llvm::Type* ret_type = DtoType(type); llvm::FunctionType* FT = llvm::FunctionType::get(ret_type, argtypes, false); // build asm call bool sideeffect = true; llvm::InlineAsm* ia = llvm::InlineAsm::get(FT, code, constraints, sideeffect); llvm::Value* rv = gIR->ir->CreateCall(ia, args.begin(), args.end(), ""); // work around missing tuple support for users of the return value if (type->ty == Tstruct) { // make a copy llvm::Value* mem = DtoAlloca(ret_type, ".__asm_tuple_ret"); TypeStruct* ts = (TypeStruct*)type; size_t n = ts->sym->fields.dim; for (size_t i = 0; i < n; i++) { llvm::Value* v = gIR->ir->CreateExtractValue(rv, i, ""); llvm::Value* gep = DtoGEPi(mem, 0, i); DtoStore(v, gep); } return new DVarValue(fd->type->nextOf(), mem); } // return call as im value return new DImValue(fd->type->nextOf(), rv); }