ldc/gen/asmstmt.cpp
2008-11-28 21:24:08 +01:00

701 lines
19 KiB
C++

// Taken from GDC source tree. Original by David Friedman.
// Released under the Artistic License found in dmd/artistic.txt
#include "gen/llvm.h"
#include "llvm/InlineAsm.h"
//#include "d-gcc-includes.h"
//#include "total.h"
#include "mars.h"
#include "statement.h"
#include "scope.h"
#include "declaration.h"
#include "dsymbol.h"
#include <cassert>
#include <deque>
#include <iostream>
#include <sstream>
#include <cstring>
//#include "d-lang.h"
//#include "d-codegen.h"
#include "gen/irstate.h"
#include "gen/dvalue.h"
#include "gen/tollvm.h"
#include "gen/logger.h"
#include "gen/todebug.h"
#include "gen/llvmhelpers.h"
typedef enum {
Arg_Integer,
Arg_Pointer,
Arg_Memory,
Arg_FrameRelative,
Arg_LocalSize,
Arg_Dollar
} AsmArgType;
typedef enum {
Mode_Input,
Mode_Output,
Mode_Update
} AsmArgMode;
struct AsmArg {
AsmArgType type;
Expression * expr;
AsmArgMode mode;
AsmArg(AsmArgType type, Expression * expr, AsmArgMode mode) {
this->type = type;
this->expr = expr;
this->mode = mode;
}
};
struct AsmCode {
char * insnTemplate;
unsigned insnTemplateLen;
Array args; // of AsmArg
std::vector<bool> regs;
unsigned dollarLabel;
int clobbersMemory;
AsmCode(int n_regs) {
insnTemplate = NULL;
insnTemplateLen = 0;
regs.resize(n_regs, false);
dollarLabel = 0;
clobbersMemory = 0;
}
};
AsmStatement::AsmStatement(Loc loc, Token *tokens) :
Statement(loc)
{
this->tokens = tokens; // Do I need to copy these?
asmcode = 0;
asmalign = 0;
refparam = 0;
naked = 0;
isBranchToLabel = NULL;
}
Statement *AsmStatement::syntaxCopy()
{
// copy tokens? copy 'code'?
AsmStatement * a_s = new AsmStatement(loc,tokens);
a_s->asmcode = asmcode;
a_s->refparam = refparam;
a_s->naked = naked;
return a_s;
}
void AsmStatement::toCBuffer(OutBuffer *buf, HdrGenState *hgs)
{
bool sep = 0, nsep = 0;
buf->writestring("asm { ");
for (Token * t = tokens; t; t = t->next) {
switch (t->value) {
case TOKlparen:
case TOKrparen:
case TOKlbracket:
case TOKrbracket:
case TOKcolon:
case TOKsemicolon:
case TOKcomma:
case TOKstring:
case TOKcharv:
case TOKwcharv:
case TOKdcharv:
nsep = 0;
break;
default:
nsep = 1;
}
if (sep + nsep == 2)
buf->writeByte(' ');
sep = nsep;
buf->writestring(t->toChars());
}
buf->writestring("; }");
buf->writenl();
}
int AsmStatement::comeFrom()
{
return FALSE;
}
struct AsmParserCommon
{
virtual void run(Scope* sc, AsmStatement* asmst) = 0;
virtual std::string getRegName(int i) = 0;
};
AsmParserCommon* asmparser = NULL;
#include "asm-x86-32.h"
#include "asm-x86-64.h"
bool d_have_inline_asm() { return true; }
Statement *AsmStatement::semantic(Scope *sc)
{
bool err = false;
if ((global.params.cpu != ARCHx86) && (global.params.cpu != ARCHx86_64))
{
error("inline asm is not supported for the \"%s\" architecture", global.params.llvmArch);
err = true;
}
if (!global.params.useInlineAsm)
{
error("inline asm is not allowed when the -noasm switch is used");
err = true;
}
if (err)
fatal();
sc->func->inlineAsm = 1;
sc->func->inlineStatus = ILSno; // %% not sure
// %% need to set DECL_UNINLINABLE too?
sc->func->hasReturnExp = 1; // %% DMD does this, apparently...
// empty statement -- still do the above things because they might be expected?
if (! tokens)
return this;
if (!asmparser)
if (global.params.cpu == ARCHx86)
asmparser = new AsmParserx8632::AsmParser;
else if (global.params.cpu == ARCHx86_64)
asmparser = new AsmParserx8664::AsmParser;
asmparser->run(sc, this);
return this;
}
int AsmStatement::blockExit()
{
//printf("AsmStatement::blockExit(%p)\n", this);
return BEfallthru | BEreturn | BEgoto | BEhalt;
}
void
AsmStatement::toIR(IRState * irs)
{
Logger::println("AsmStatement::toIR(): %s", loc.toChars());
LOG_SCOPE;
// sanity check
assert(irs->func()->decl->inlineAsm);
// get asm block
IRAsmBlock* asmblock = irs->asmBlock;
assert(asmblock);
// debug info
if (global.params.symdebug)
DtoDwarfStopPoint(loc.linnum);
if (! asmcode)
return;
static std::string i_cns = "i";
static std::string p_cns = "i";
static std::string m_cns = "*m";
static std::string mw_cns = "=*m";
static std::string mrw_cns = "+*m";
static std::string memory_name = "memory";
AsmCode * code = (AsmCode *) asmcode;
std::deque<LLValue*> input_values;
std::deque<std::string> input_constraints;
std::deque<LLValue*> output_values;
std::deque<std::string> output_constraints;
std::deque<std::string> clobbers;
// FIXME
#define HOST_WIDE_INT long
HOST_WIDE_INT var_frame_offset; // "frame_offset" is a macro
bool clobbers_mem = code->clobbersMemory;
int input_idx = 0;
int n_outputs = 0;
int arg_map[10];
assert(code->args.dim <= 10);
for (unsigned i = 0; i < code->args.dim; i++) {
AsmArg * arg = (AsmArg *) code->args.data[i];
bool is_input = true;
LLValue* arg_val = 0;
std::string cns;
switch (arg->type) {
case Arg_Integer:
arg_val = arg->expr->toElem(irs)->getRVal();
do_integer:
cns = i_cns;
break;
case Arg_Pointer:
assert(arg->expr->op == TOKvar);
arg_val = arg->expr->toElem(irs)->getRVal();
cns = p_cns;
break;
case Arg_Memory:
arg_val = arg->expr->toElem(irs)->getRVal();
switch (arg->mode) {
case Mode_Input: cns = m_cns; break;
case Mode_Output: cns = mw_cns; is_input = false; break;
case Mode_Update: cns = mrw_cns; is_input = false; break;
default: assert(0); break;
}
break;
case Arg_FrameRelative:
// FIXME
std::cout << "asm fixme Arg_FrameRelative" << std::endl;
assert(0);
/* if (arg->expr->op == TOKvar)
arg_val = ((VarExp *) arg->expr)->var->toSymbol()->Stree;
else
assert(0);
if ( getFrameRelativeValue(arg_val, & var_frame_offset) ) {
// arg_val = irs->integerConstant(var_frame_offset);
cns = i_cns;
} else {
this->error("%s", "argument not frame relative");
return;
}
if (arg->mode != Mode_Input)
clobbers_mem = true;
break;*/
case Arg_LocalSize:
// FIXME
std::cout << "asm fixme Arg_LocalSize" << std::endl;
assert(0);
/* var_frame_offset = cfun->x_frame_offset;
if (var_frame_offset < 0)
var_frame_offset = - var_frame_offset;
arg_val = irs->integerConstant( var_frame_offset );*/
goto do_integer;
default:
assert(0);
}
if (is_input) {
arg_map[i] = --input_idx;
//inputs.cons(tree_cons(NULL_TREE, cns, NULL_TREE), arg_val);
input_values.push_back(arg_val);
input_constraints.push_back(cns);
} else {
arg_map[i] = n_outputs++;
//outputs.cons(tree_cons(NULL_TREE, cns, NULL_TREE), arg_val);
output_values.push_back(arg_val);
output_constraints.push_back(cns);
}
}
// Telling GCC that callee-saved registers are clobbered makes it preserve
// those registers. This changes the stack from what a naked function
// expects.
// FIXME
// if (! irs->func->naked) {
assert(asmparser);
for (int i = 0; i < code->regs.size(); i++) {
if (code->regs[i]) {
//clobbers.cons(NULL_TREE, regInfo[i].gccName);
clobbers.push_back(asmparser->getRegName(i));
}
}
if (clobbers_mem)
clobbers.push_back(memory_name);
//clobbers.cons(NULL_TREE, memory_name);
// }
// Remap argument numbers
for (unsigned i = 0; i < code->args.dim; i++) {
if (arg_map[i] < 0)
arg_map[i] = -arg_map[i] - 1 + n_outputs;
}
bool pct = false;
char * p = code->insnTemplate;
char * q = p + code->insnTemplateLen;
//printf("start: %.*s\n", code->insnTemplateLen, code->insnTemplate);
while (p < q) {
if (pct) {
if (*p >= '0' && *p <= '9') {
// %% doesn't check against nargs
*p = '0' + arg_map[*p - '0'];
pct = false;
} else if (*p == '$') {
pct = false;
}
//assert(*p == '%');// could be 'a', etc. so forget it..
} else if (*p == '$')
pct = true;
++p;
}
Logger::println("final asm: %.*s", code->insnTemplateLen, code->insnTemplate);
std::string insnt(code->insnTemplate, code->insnTemplateLen);
// rewrite GCC-style constraints to LLVM-style constraints
std::string llvmOutConstraints;
std::string llvmInConstraints;
int n = 0;
typedef std::deque<std::string>::iterator it;
for(it i = output_constraints.begin(), e = output_constraints.end(); i != e; ++i, ++n) {
// rewrite update constraint to in and out constraints
if((*i)[0] == '+') {
(*i)[0] = '=';
std::string input_constraint;
std::stringstream ss;
ss << n;
ss >> input_constraint;
//FIXME: I think multiple inout constraints will mess up the order!
input_constraints.push_front(input_constraint);
input_values.push_front(output_values[n]);
}
llvmOutConstraints += *i;
llvmOutConstraints += ",";
}
for(it i = input_constraints.begin(), e = input_constraints.end(); i != e; ++i) {
llvmInConstraints += *i;
llvmInConstraints += ",";
}
std::string clobstr;
for(it i = clobbers.begin(), e = clobbers.end(); i != e; ++i) {
clobstr = "~{" + *i + "},";
asmblock->clobs.insert(clobstr);
}
// excessive commas are removed later...
// push asm statement
IRAsmStmt* asmStmt = new IRAsmStmt;
asmStmt->code = insnt;
asmStmt->out_c = llvmOutConstraints;
asmStmt->in_c = llvmInConstraints;
asmStmt->out.insert(asmStmt->out.begin(), output_values.begin(), output_values.end());
asmStmt->in.insert(asmStmt->in.begin(), input_values.begin(), input_values.end());
asmStmt->isBranchToLabel = isBranchToLabel;
asmblock->s.push_back(asmStmt);
}
//////////////////////////////////////////////////////////////////////////////
AsmBlockStatement::AsmBlockStatement(Loc loc, Statements* s)
: CompoundStatement(loc, s)
{
enclosinghandler = NULL;
tf = NULL;
}
// rewrite argument indices to the block scope indices
static void remap_outargs(std::string& insnt, size_t nargs, size_t& idx)
{
static const std::string digits[10] =
{
"0","1","2","3","4",
"5","6","7","8","9"
};
assert(nargs <= 10);
static const std::string prefix("<<out");
static const std::string suffix(">>");
std::string argnum;
std::string needle;
char buf[10];
for (unsigned i = 0; i < nargs; i++) {
needle = prefix + digits[i] + suffix;
size_t pos = insnt.find(needle);
if(std::string::npos != pos)
sprintf(buf, "%" PRIuSIZE, idx++);
while(std::string::npos != (pos = insnt.find(needle)))
insnt.replace(pos, needle.size(), buf);
}
}
// rewrite argument indices to the block scope indices
static void remap_inargs(std::string& insnt, size_t nargs, size_t& idx)
{
static const std::string digits[10] =
{
"0","1","2","3","4",
"5","6","7","8","9"
};
assert(nargs <= 10);
static const std::string prefix("<<in");
static const std::string suffix(">>");
std::string argnum;
std::string needle;
char buf[10];
for (unsigned i = 0; i < nargs; i++) {
needle = prefix + digits[i] + suffix;
size_t pos = insnt.find(needle);
if(std::string::npos != pos)
sprintf(buf, "%" PRIuSIZE, idx++);
while(std::string::npos != (pos = insnt.find(needle)))
insnt.replace(pos, needle.size(), buf);
}
}
void AsmBlockStatement::toIR(IRState* p)
{
Logger::println("AsmBlockStatement::toIR(): %s", loc.toChars());
LOG_SCOPE;
Logger::println("BEGIN ASM");
// disable inlining
gIR->func()->setNeverInline();
// create asm block structure
assert(!p->asmBlock);
IRAsmBlock* asmblock = new IRAsmBlock;
assert(asmblock);
p->asmBlock = asmblock;
// do asm statements
for (int i=0; i<statements->dim; i++)
{
Statement* s = (Statement*)statements->data[i];
if (s) {
s->toIR(p);
}
}
// build forwarder for in-asm branches to external labels
// this additional asm code sets the __llvm_jump_target variable
// to a unique value that will identify the jump target in
// a post-asm switch
// maps each goto destination to its special value
std::map<Identifier*, int> gotoToVal;
// location of the special value determining the goto label
// will be set if post-asm dispatcher block is needed
llvm::AllocaInst* jump_target;
{
FuncDeclaration* fd = gIR->func()->decl;
char* fdmangle = fd->mangle();
// we use a simple static counter to make sure the new end labels are unique
static size_t uniqueLabelsId = 0;
std::ostringstream asmGotoEndLabel;
asmGotoEndLabel << "." << fdmangle << "__llvm_asm_end" << uniqueLabelsId++;
// initialize the setter statement we're going to build
IRAsmStmt* outSetterStmt = new IRAsmStmt;
std::string asmGotoEnd = "jmp "+asmGotoEndLabel.str()+" ; ";
std::ostringstream code;
code << asmGotoEnd;
int n_goto = 1;
size_t n = asmblock->s.size();
for(size_t i=0; i<n; ++i)
{
IRAsmStmt* a = asmblock->s[i];
// skip non-branch statements
if(!a->isBranchToLabel)
continue;
// if internal, no special handling is necessary, skip
std::vector<Identifier*>::const_iterator it, end;
end = asmblock->internalLabels.end();
bool skip = false;
for(it = asmblock->internalLabels.begin(); it != end; ++it)
if((*it)->equals(a->isBranchToLabel))
skip = true;
if(skip)
continue;
// if we already set things up for this branch target, skip
if(gotoToVal.find(a->isBranchToLabel) != gotoToVal.end())
continue;
// record that the jump needs to be handled in the post-asm dispatcher
gotoToVal[a->isBranchToLabel] = n_goto;
// provide an in-asm target for the branch and set value
Logger::println("statement '%s' references outer label '%s': creating forwarder", a->code.c_str(), a->isBranchToLabel->string);
code << fdmangle << '_' << a->isBranchToLabel->string << ": ; ";
code << "movl $<<in" << n_goto << ">>, $<<out0>> ; ";
//FIXME: Store the value -> label mapping somewhere, so it can be referenced later
outSetterStmt->in.push_back(DtoConstUint(n_goto));
outSetterStmt->in_c += "i,";
code << asmGotoEnd;
++n_goto;
}
if(code.str() != asmGotoEnd)
{
// finalize code
outSetterStmt->code = code.str();
outSetterStmt->code += asmGotoEndLabel.str()+": ; ";
// create storage for and initialize the temporary
jump_target = DtoAlloca(LLType::Int32Ty, "__llvm_jump_target");
gIR->ir->CreateStore(DtoConstUint(0), jump_target);
// setup variable for output from asm
outSetterStmt->out_c = "=*m,";
outSetterStmt->out.push_back(jump_target);
asmblock->s.push_back(outSetterStmt);
}
else
delete outSetterStmt;
}
// build asm block
std::vector<LLValue*> outargs;
std::vector<LLValue*> inargs;
std::vector<const LLType*> outtypes;
std::vector<const LLType*> intypes;
std::string out_c;
std::string in_c;
std::string clobbers;
std::string code;
size_t asmIdx = 0;
size_t n = asmblock->s.size();
for (size_t i=0; i<n; ++i)
{
IRAsmStmt* a = asmblock->s[i];
assert(a);
size_t onn = a->out.size();
for (size_t j=0; j<onn; ++j)
{
outargs.push_back(a->out[j]);
outtypes.push_back(a->out[j]->getType());
}
if (!a->out_c.empty())
{
out_c += a->out_c;
}
remap_outargs(a->code, onn+a->in.size(), asmIdx);
}
for (size_t i=0; i<n; ++i)
{
IRAsmStmt* a = asmblock->s[i];
assert(a);
size_t inn = a->in.size();
for (size_t j=0; j<inn; ++j)
{
inargs.push_back(a->in[j]);
intypes.push_back(a->in[j]->getType());
}
if (!a->in_c.empty())
{
in_c += a->in_c;
}
remap_inargs(a->code, inn+a->out.size(), asmIdx);
if (!code.empty())
code += " ; ";
code += a->code;
}
asmblock->s.clear();
// append inputs
out_c += in_c;
// append clobbers
typedef std::set<std::string>::iterator clobs_it;
for (clobs_it i=asmblock->clobs.begin(); i!=asmblock->clobs.end(); ++i)
{
out_c += *i;
}
// remove excessive comma
if (!out_c.empty())
out_c.resize(out_c.size()-1);
Logger::println("code = \"%s\"", code.c_str());
Logger::println("constraints = \"%s\"", out_c.c_str());
std::vector<const LLType*> types;
types.insert(types.end(), outtypes.begin(), outtypes.end());
types.insert(types.end(), intypes.begin(), intypes.end());
llvm::FunctionType* fty = llvm::FunctionType::get(llvm::Type::VoidTy, types, false);
if (Logger::enabled())
Logger::cout() << "function type = " << *fty << '\n';
llvm::InlineAsm* ia = llvm::InlineAsm::get(fty, code, out_c, true);
std::vector<LLValue*> args;
args.insert(args.end(), outargs.begin(), outargs.end());
args.insert(args.end(), inargs.begin(), inargs.end());
llvm::CallInst* call = p->ir->CreateCall(ia, args.begin(), args.end(), "");
p->asmBlock = NULL;
Logger::println("END ASM");
// if asm contained external branches, emit goto forwarder code
if(!gotoToVal.empty())
{
assert(jump_target);
// make new blocks
llvm::BasicBlock* oldend = gIR->scopeend();
llvm::BasicBlock* bb = llvm::BasicBlock::Create("afterasmgotoforwarder", p->topfunc(), oldend);
llvm::LoadInst* val = p->ir->CreateLoad(jump_target, "__llvm_jump_target_value");
llvm::SwitchInst* sw = p->ir->CreateSwitch(val, bb, gotoToVal.size());
// add all cases
std::map<Identifier*, int>::iterator it, end = gotoToVal.end();
for(it = gotoToVal.begin(); it != end; ++it)
{
llvm::BasicBlock* casebb = llvm::BasicBlock::Create("case", p->topfunc(), bb);
sw->addCase(llvm::ConstantInt::get(llvm::IntegerType::get(32), it->second), casebb);
p->scope() = IRScope(casebb,bb);
DtoGoto(&loc, it->first, enclosinghandler, tf);
}
p->scope() = IRScope(bb,oldend);
}
}
// the whole idea of this statement is to avoid the flattening
Statements* AsmBlockStatement::flatten(Scope* sc)
{
return NULL;
}
Statement *AsmBlockStatement::syntaxCopy()
{
Statements *a = new Statements();
a->setDim(statements->dim);
for (size_t i = 0; i < statements->dim; i++)
{
Statement *s = (Statement *)statements->data[i];
if (s)
s = s->syntaxCopy();
a->data[i] = s;
}
AsmBlockStatement *cs = new AsmBlockStatement(loc, a);
return cs;
}
// necessary for in-asm branches
Statement *AsmBlockStatement::semantic(Scope *sc)
{
enclosinghandler = sc->tfOfTry;
tf = sc->tf;
return CompoundStatement::semantic(sc);
}