blob: 8a68f05b2cc24713801b74f89781f9bd0a991ed9 [file] [log] [blame]
/*
* Linearize - walk the statement tree (but _not_ the expressions)
* to generate a linear version of it and the basic blocks.
*
* NOTE! We're not interested in the actual sub-expressions yet,
* even though they can generate conditional branches and
* subroutine calls. That's all "local" behaviour.
*
* Copyright (C) 2004 Linus Torvalds
* Copyright (C) 2004 Christopher Li
*/
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include "parse.h"
#include "expression.h"
#include "linearize.h"
#include "flow.h"
#include "target.h"
pseudo_t linearize_statement(struct entrypoint *ep, struct statement *stmt);
pseudo_t linearize_expression(struct entrypoint *ep, struct expression *expr);
static pseudo_t add_binary_op(struct entrypoint *ep, struct symbol *ctype, int op, pseudo_t left, pseudo_t right);
static pseudo_t add_setval(struct entrypoint *ep, struct symbol *ctype, struct expression *val);
static pseudo_t linearize_one_symbol(struct entrypoint *ep, struct symbol *sym);
struct access_data;
static pseudo_t add_load(struct entrypoint *ep, struct access_data *);
static pseudo_t linearize_initializer(struct entrypoint *ep, struct expression *initializer, struct access_data *);
struct pseudo void_pseudo = {};
static struct position current_pos;
ALLOCATOR(pseudo_user, "pseudo_user");
static struct instruction *alloc_instruction(int opcode, int size)
{
struct instruction * insn = __alloc_instruction(0);
insn->opcode = opcode;
insn->size = size;
insn->pos = current_pos;
return insn;
}
static inline int type_size(struct symbol *type)
{
return type ? type->bit_size > 0 ? type->bit_size : 0 : 0;
}
static struct instruction *alloc_typed_instruction(int opcode, struct symbol *type)
{
return alloc_instruction(opcode, type_size(type));
}
static struct entrypoint *alloc_entrypoint(void)
{
return __alloc_entrypoint(0);
}
static struct basic_block *alloc_basic_block(struct entrypoint *ep, struct position pos)
{
struct basic_block *bb = __alloc_basic_block(0);
bb->context = -1;
bb->pos = pos;
bb->ep = ep;
return bb;
}
static struct multijmp *alloc_multijmp(struct basic_block *target, int begin, int end)
{
struct multijmp *multijmp = __alloc_multijmp(0);
multijmp->target = target;
multijmp->begin = begin;
multijmp->end = end;
return multijmp;
}
static inline int regno(pseudo_t n)
{
int retval = -1;
if (n && n->type == PSEUDO_REG)
retval = n->nr;
return retval;
}
const char *show_pseudo(pseudo_t pseudo)
{
static int n;
static char buffer[4][64];
char *buf;
int i;
if (!pseudo)
return "no pseudo";
if (pseudo == VOID)
return "VOID";
buf = buffer[3 & ++n];
switch(pseudo->type) {
case PSEUDO_SYM: {
struct symbol *sym = pseudo->sym;
struct expression *expr;
if (sym->bb_target) {
snprintf(buf, 64, ".L%p", sym->bb_target);
break;
}
if (sym->ident) {
snprintf(buf, 64, "%s", show_ident(sym->ident));
break;
}
expr = sym->initializer;
snprintf(buf, 64, "<anon symbol:%p>", sym);
if (expr) {
switch (expr->type) {
case EXPR_VALUE:
snprintf(buf, 64, "<symbol value: %lld>", expr->value);
break;
case EXPR_STRING:
return show_string(expr->string);
default:
break;
}
}
break;
}
case PSEUDO_REG:
i = snprintf(buf, 64, "%%r%d", pseudo->nr);
if (pseudo->ident)
sprintf(buf+i, "(%s)", show_ident(pseudo->ident));
break;
case PSEUDO_VAL: {
long long value = pseudo->value;
if (value > 1000 || value < -1000)
snprintf(buf, 64, "$%#llx", value);
else
snprintf(buf, 64, "$%lld", value);
break;
}
case PSEUDO_ARG:
snprintf(buf, 64, "%%arg%d", pseudo->nr);
break;
case PSEUDO_PHI:
i = snprintf(buf, 64, "%%phi%d", pseudo->nr);
if (pseudo->ident)
sprintf(buf+i, "(%s)", show_ident(pseudo->ident));
break;
default:
snprintf(buf, 64, "<bad pseudo type %d>", pseudo->type);
}
return buf;
}
static const char *opcodes[] = {
[OP_BADOP] = "bad_op",
/* Fn entrypoint */
[OP_ENTRY] = "<entry-point>",
/* Terminator */
[OP_RET] = "ret",
[OP_BR] = "br",
[OP_SWITCH] = "switch",
[OP_INVOKE] = "invoke",
[OP_COMPUTEDGOTO] = "jmp *",
[OP_UNWIND] = "unwind",
/* Binary */
[OP_ADD] = "add",
[OP_SUB] = "sub",
[OP_MULU] = "mulu",
[OP_MULS] = "muls",
[OP_DIVU] = "divu",
[OP_DIVS] = "divs",
[OP_MODU] = "modu",
[OP_MODS] = "mods",
[OP_SHL] = "shl",
[OP_LSR] = "lsr",
[OP_ASR] = "asr",
/* Logical */
[OP_AND] = "and",
[OP_OR] = "or",
[OP_XOR] = "xor",
[OP_AND_BOOL] = "and-bool",
[OP_OR_BOOL] = "or-bool",
/* Binary comparison */
[OP_SET_EQ] = "seteq",
[OP_SET_NE] = "setne",
[OP_SET_LE] = "setle",
[OP_SET_GE] = "setge",
[OP_SET_LT] = "setlt",
[OP_SET_GT] = "setgt",
[OP_SET_B] = "setb",
[OP_SET_A] = "seta",
[OP_SET_BE] = "setbe",
[OP_SET_AE] = "setae",
/* Uni */
[OP_NOT] = "not",
[OP_NEG] = "neg",
/* Special three-input */
[OP_SEL] = "select",
/* Memory */
[OP_MALLOC] = "malloc",
[OP_FREE] = "free",
[OP_ALLOCA] = "alloca",
[OP_LOAD] = "load",
[OP_STORE] = "store",
[OP_SETVAL] = "set",
[OP_SYMADDR] = "symaddr",
[OP_GET_ELEMENT_PTR] = "getelem",
/* Other */
[OP_PHI] = "phi",
[OP_PHISOURCE] = "phisrc",
[OP_CAST] = "cast",
[OP_SCAST] = "scast",
[OP_FPCAST] = "fpcast",
[OP_PTRCAST] = "ptrcast",
[OP_INLINED_CALL] = "# call",
[OP_CALL] = "call",
[OP_VANEXT] = "va_next",
[OP_VAARG] = "va_arg",
[OP_SLICE] = "slice",
[OP_SNOP] = "snop",
[OP_LNOP] = "lnop",
[OP_NOP] = "nop",
[OP_DEATHNOTE] = "dead",
[OP_ASM] = "asm",
/* Sparse tagging (line numbers, context, whatever) */
[OP_CONTEXT] = "context",
[OP_RANGE] = "range-check",
[OP_COPY] = "copy",
};
static char *show_asm_constraints(char *buf, const char *sep, struct asm_constraint_list *list)
{
struct asm_constraint *entry;
FOR_EACH_PTR(list, entry) {
buf += sprintf(buf, "%s\"%s\"", sep, entry->constraint);
if (entry->pseudo)
buf += sprintf(buf, " (%s)", show_pseudo(entry->pseudo));
if (entry->ident)
buf += sprintf(buf, " [%s]", show_ident(entry->ident));
sep = ", ";
} END_FOR_EACH_PTR(entry);
return buf;
}
static char *show_asm(char *buf, struct instruction *insn)
{
struct asm_rules *rules = insn->asm_rules;
buf += sprintf(buf, "\"%s\"", insn->string);
buf = show_asm_constraints(buf, "\n\t\tout: ", rules->outputs);
buf = show_asm_constraints(buf, "\n\t\tin: ", rules->inputs);
buf = show_asm_constraints(buf, "\n\t\tclobber: ", rules->clobbers);
return buf;
}
const char *show_instruction(struct instruction *insn)
{
int opcode = insn->opcode;
static char buffer[4096];
char *buf;
buf = buffer;
if (!insn->bb)
buf += sprintf(buf, "# ");
if (opcode < sizeof(opcodes)/sizeof(char *)) {
const char *op = opcodes[opcode];
if (!op)
buf += sprintf(buf, "opcode:%d", opcode);
else
buf += sprintf(buf, "%s", op);
if (insn->size)
buf += sprintf(buf, ".%d", insn->size);
memset(buf, ' ', 20);
buf++;
}
if (buf < buffer + 12)
buf = buffer + 12;
switch (opcode) {
case OP_RET:
if (insn->src && insn->src != VOID)
buf += sprintf(buf, "%s", show_pseudo(insn->src));
break;
case OP_BR:
if (insn->bb_true && insn->bb_false) {
buf += sprintf(buf, "%s, .L%p, .L%p", show_pseudo(insn->cond), insn->bb_true, insn->bb_false);
break;
}
buf += sprintf(buf, ".L%p", insn->bb_true ? insn->bb_true : insn->bb_false);
break;
case OP_SYMADDR: {
struct symbol *sym = insn->symbol->sym;
buf += sprintf(buf, "%s <- ", show_pseudo(insn->target));
if (sym->bb_target) {
buf += sprintf(buf, ".L%p", sym->bb_target);
break;
}
if (sym->ident) {
buf += sprintf(buf, "%s", show_ident(sym->ident));
break;
}
buf += sprintf(buf, "<anon symbol:%p>", sym);
break;
}
case OP_SETVAL: {
struct expression *expr = insn->val;
buf += sprintf(buf, "%s <- ", show_pseudo(insn->target));
if (!expr) {
buf += sprintf(buf, "%s", "<none>");
break;
}
switch (expr->type) {
case EXPR_VALUE:
buf += sprintf(buf, "%lld", expr->value);
break;
case EXPR_FVALUE:
buf += sprintf(buf, "%Lf", expr->fvalue);
break;
case EXPR_STRING:
buf += sprintf(buf, "%.40s", show_string(expr->string));
break;
case EXPR_SYMBOL:
buf += sprintf(buf, "%s", show_ident(expr->symbol->ident));
break;
case EXPR_LABEL:
buf += sprintf(buf, ".L%p", expr->symbol->bb_target);
break;
default:
buf += sprintf(buf, "SETVAL EXPR TYPE %d", expr->type);
}
break;
}
case OP_SWITCH: {
struct multijmp *jmp;
buf += sprintf(buf, "%s", show_pseudo(insn->target));
FOR_EACH_PTR(insn->multijmp_list, jmp) {
if (jmp->begin == jmp->end)
buf += sprintf(buf, ", %d -> .L%p", jmp->begin, jmp->target);
else if (jmp->begin < jmp->end)
buf += sprintf(buf, ", %d ... %d -> .L%p", jmp->begin, jmp->end, jmp->target);
else
buf += sprintf(buf, ", default -> .L%p", jmp->target);
} END_FOR_EACH_PTR(jmp);
break;
}
case OP_COMPUTEDGOTO: {
struct multijmp *jmp;
buf += sprintf(buf, "%s", show_pseudo(insn->target));
FOR_EACH_PTR(insn->multijmp_list, jmp) {
buf += sprintf(buf, ", .L%p", jmp->target);
} END_FOR_EACH_PTR(jmp);
break;
}
case OP_PHISOURCE: {
struct instruction *phi;
buf += sprintf(buf, "%s <- %s ", show_pseudo(insn->target), show_pseudo(insn->phi_src));
FOR_EACH_PTR(insn->phi_users, phi) {
buf += sprintf(buf, " (%s)", show_pseudo(phi->target));
} END_FOR_EACH_PTR(phi);
break;
}
case OP_PHI: {
pseudo_t phi;
const char *s = " <-";
buf += sprintf(buf, "%s", show_pseudo(insn->target));
FOR_EACH_PTR(insn->phi_list, phi) {
buf += sprintf(buf, "%s %s", s, show_pseudo(phi));
s = ",";
} END_FOR_EACH_PTR(phi);
break;
}
case OP_LOAD: case OP_LNOP:
buf += sprintf(buf, "%s <- %d[%s]", show_pseudo(insn->target), insn->offset, show_pseudo(insn->src));
break;
case OP_STORE: case OP_SNOP:
buf += sprintf(buf, "%s -> %d[%s]", show_pseudo(insn->target), insn->offset, show_pseudo(insn->src));
break;
case OP_INLINED_CALL:
case OP_CALL: {
struct pseudo *arg;
if (insn->target && insn->target != VOID)
buf += sprintf(buf, "%s <- ", show_pseudo(insn->target));
buf += sprintf(buf, "%s", show_pseudo(insn->func));
FOR_EACH_PTR(insn->arguments, arg) {
buf += sprintf(buf, ", %s", show_pseudo(arg));
} END_FOR_EACH_PTR(arg);
break;
}
case OP_CAST:
case OP_SCAST:
case OP_FPCAST:
case OP_PTRCAST:
buf += sprintf(buf, "%s <- (%d) %s",
show_pseudo(insn->target),
type_size(insn->orig_type),
show_pseudo(insn->src));
break;
case OP_BINARY ... OP_BINARY_END:
case OP_BINCMP ... OP_BINCMP_END:
buf += sprintf(buf, "%s <- %s, %s", show_pseudo(insn->target), show_pseudo(insn->src1), show_pseudo(insn->src2));
break;
case OP_SEL:
buf += sprintf(buf, "%s <- %s, %s, %s", show_pseudo(insn->target),
show_pseudo(insn->src1), show_pseudo(insn->src2), show_pseudo(insn->src3));
break;
case OP_SLICE:
buf += sprintf(buf, "%s <- %s, %d, %d", show_pseudo(insn->target), show_pseudo(insn->base), insn->from, insn->len);
break;
case OP_NOT: case OP_NEG:
buf += sprintf(buf, "%s <- %s", show_pseudo(insn->target), show_pseudo(insn->src1));
break;
case OP_CONTEXT:
buf += sprintf(buf, "%s%d", insn->check ? "check: " : "", insn->increment);
break;
case OP_RANGE:
buf += sprintf(buf, "%s between %s..%s", show_pseudo(insn->src1), show_pseudo(insn->src2), show_pseudo(insn->src3));
break;
case OP_NOP:
buf += sprintf(buf, "%s <- %s", show_pseudo(insn->target), show_pseudo(insn->src1));
break;
case OP_DEATHNOTE:
buf += sprintf(buf, "%s", show_pseudo(insn->target));
break;
case OP_ASM:
buf = show_asm(buf, insn);
break;
case OP_COPY:
buf += sprintf(buf, "%s <- %s", show_pseudo(insn->target), show_pseudo(insn->src));
break;
default:
break;
}
if (buf >= buffer + sizeof(buffer))
die("instruction buffer overflowed %td\n", buf - buffer);
do { --buf; } while (*buf == ' ');
*++buf = 0;
return buffer;
}
void show_bb(struct basic_block *bb)
{
struct instruction *insn;
printf(".L%p:\n", bb);
if (verbose) {
pseudo_t needs, defines;
printf("%s:%d\n", stream_name(bb->pos.stream), bb->pos.line);
FOR_EACH_PTR(bb->needs, needs) {
struct instruction *def = needs->def;
if (def->opcode != OP_PHI) {
printf(" **uses %s (from .L%p)**\n", show_pseudo(needs), def->bb);
} else {
pseudo_t phi;
const char *sep = " ";
printf(" **uses %s (from", show_pseudo(needs));
FOR_EACH_PTR(def->phi_list, phi) {
if (phi == VOID)
continue;
printf("%s(%s:.L%p)", sep, show_pseudo(phi), phi->def->bb);
sep = ", ";
} END_FOR_EACH_PTR(phi);
printf(")**\n");
}
} END_FOR_EACH_PTR(needs);
FOR_EACH_PTR(bb->defines, defines) {
printf(" **defines %s **\n", show_pseudo(defines));
} END_FOR_EACH_PTR(defines);
if (bb->parents) {
struct basic_block *from;
FOR_EACH_PTR(bb->parents, from) {
printf(" **from %p (%s:%d:%d)**\n", from,
stream_name(from->pos.stream), from->pos.line, from->pos.pos);
} END_FOR_EACH_PTR(from);
}
if (bb->children) {
struct basic_block *to;
FOR_EACH_PTR(bb->children, to) {
printf(" **to %p (%s:%d:%d)**\n", to,
stream_name(to->pos.stream), to->pos.line, to->pos.pos);
} END_FOR_EACH_PTR(to);
}
}
FOR_EACH_PTR(bb->insns, insn) {
if (!insn->bb && verbose < 2)
continue;
printf("\t%s\n", show_instruction(insn));
} END_FOR_EACH_PTR(insn);
if (!bb_terminated(bb))
printf("\tEND\n");
}
static void show_symbol_usage(pseudo_t pseudo)
{
struct pseudo_user *pu;
if (pseudo) {
FOR_EACH_PTR(pseudo->users, pu) {
printf("\t%s\n", show_instruction(pu->insn));
} END_FOR_EACH_PTR(pu);
}
}
void show_entry(struct entrypoint *ep)
{
struct symbol *sym;
struct basic_block *bb;
printf("%s:\n", show_ident(ep->name->ident));
if (verbose) {
printf("ep %p: %s\n", ep, show_ident(ep->name->ident));
FOR_EACH_PTR(ep->syms, sym) {
if (!sym->pseudo)
continue;
if (!sym->pseudo->users)
continue;
printf(" sym: %p %s\n", sym, show_ident(sym->ident));
if (sym->ctype.modifiers & (MOD_EXTERN | MOD_STATIC | MOD_ADDRESSABLE))
printf("\texternal visibility\n");
show_symbol_usage(sym->pseudo);
} END_FOR_EACH_PTR(sym);
printf("\n");
}
FOR_EACH_PTR(ep->bbs, bb) {
if (!bb)
continue;
if (!bb->parents && !bb->children && !bb->insns && verbose < 2)
continue;
show_bb(bb);
printf("\n");
} END_FOR_EACH_PTR(bb);
printf("\n");
}
static void bind_label(struct symbol *label, struct basic_block *bb, struct position pos)
{
if (label->bb_target)
warning(pos, "label '%s' already bound", show_ident(label->ident));
label->bb_target = bb;
}
static struct basic_block * get_bound_block(struct entrypoint *ep, struct symbol *label)
{
struct basic_block *bb = label->bb_target;
if (!bb) {
bb = alloc_basic_block(ep, label->pos);
label->bb_target = bb;
}
return bb;
}
static void finish_block(struct entrypoint *ep)
{
struct basic_block *src = ep->active;
if (bb_reachable(src))
ep->active = NULL;
}
static void add_goto(struct entrypoint *ep, struct basic_block *dst)
{
struct basic_block *src = ep->active;
if (bb_reachable(src)) {
struct instruction *br = alloc_instruction(OP_BR, 0);
br->bb_true = dst;
add_bb(&dst->parents, src);
add_bb(&src->children, dst);
br->bb = src;
add_instruction(&src->insns, br);
ep->active = NULL;
}
}
static void add_one_insn(struct entrypoint *ep, struct instruction *insn)
{
struct basic_block *bb = ep->active;
if (bb_reachable(bb)) {
insn->bb = bb;
add_instruction(&bb->insns, insn);
}
}
static void set_activeblock(struct entrypoint *ep, struct basic_block *bb)
{
if (!bb_terminated(ep->active))
add_goto(ep, bb);
ep->active = bb;
if (bb_reachable(bb))
add_bb(&ep->bbs, bb);
}
static void remove_parent(struct basic_block *child, struct basic_block *parent)
{
remove_bb_from_list(&child->parents, parent, 1);
if (!child->parents)
kill_bb(child);
}
/* Change a "switch" into a branch */
void insert_branch(struct basic_block *bb, struct instruction *jmp, struct basic_block *target)
{
struct instruction *br, *old;
struct basic_block *child;
/* Remove the switch */
old = delete_last_instruction(&bb->insns);
assert(old == jmp);
br = alloc_instruction(OP_BR, 0);
br->bb = bb;
br->bb_true = target;
add_instruction(&bb->insns, br);
FOR_EACH_PTR(bb->children, child) {
if (child == target) {
target = NULL; /* Trigger just once */
continue;
}
DELETE_CURRENT_PTR(child);
remove_parent(child, bb);
} END_FOR_EACH_PTR(child);
PACK_PTR_LIST(&bb->children);
}
void insert_select(struct basic_block *bb, struct instruction *br, struct instruction *phi_node, pseudo_t true, pseudo_t false)
{
pseudo_t target;
struct instruction *select;
/* Remove the 'br' */
delete_last_instruction(&bb->insns);
select = alloc_instruction(OP_SEL, phi_node->size);
select->bb = bb;
assert(br->cond);
use_pseudo(select, br->cond, &select->src1);
target = phi_node->target;
assert(target->def == phi_node);
select->target = target;
target->def = select;
use_pseudo(select, true, &select->src2);
use_pseudo(select, false, &select->src3);
add_instruction(&bb->insns, select);
add_instruction(&bb->insns, br);
}
static inline int bb_empty(struct basic_block *bb)
{
return !bb->insns;
}
/* Add a label to the currently active block, return new active block */
static struct basic_block * add_label(struct entrypoint *ep, struct symbol *label)
{
struct basic_block *bb = label->bb_target;
if (bb) {
set_activeblock(ep, bb);
return bb;
}
bb = ep->active;
if (!bb_reachable(bb) || !bb_empty(bb)) {
bb = alloc_basic_block(ep, label->pos);
set_activeblock(ep, bb);
}
label->bb_target = bb;
return bb;
}
static void add_branch(struct entrypoint *ep, struct expression *expr, pseudo_t cond, struct basic_block *bb_true, struct basic_block *bb_false)
{
struct basic_block *bb = ep->active;
struct instruction *br;
if (bb_reachable(bb)) {
br = alloc_instruction(OP_BR, 0);
use_pseudo(br, cond, &br->cond);
br->bb_true = bb_true;
br->bb_false = bb_false;
add_bb(&bb_true->parents, bb);
add_bb(&bb_false->parents, bb);
add_bb(&bb->children, bb_true);
add_bb(&bb->children, bb_false);
add_one_insn(ep, br);
}
}
/* Dummy pseudo allocator */
pseudo_t alloc_pseudo(struct instruction *def)
{
static int nr = 0;
struct pseudo * pseudo = __alloc_pseudo(0);
pseudo->type = PSEUDO_REG;
pseudo->nr = ++nr;
pseudo->def = def;
return pseudo;
}
static void clear_symbol_pseudos(struct entrypoint *ep)
{
pseudo_t pseudo;
FOR_EACH_PTR(ep->accesses, pseudo) {
pseudo->sym->pseudo = NULL;
} END_FOR_EACH_PTR(pseudo);
}
static pseudo_t symbol_pseudo(struct entrypoint *ep, struct symbol *sym)
{
pseudo_t pseudo;
if (!sym)
return VOID;
pseudo = sym->pseudo;
if (!pseudo) {
pseudo = __alloc_pseudo(0);
pseudo->nr = -1;
pseudo->type = PSEUDO_SYM;
pseudo->sym = sym;
pseudo->ident = sym->ident;
sym->pseudo = pseudo;
add_pseudo(&ep->accesses, pseudo);
}
/* Symbol pseudos have neither nr, usage nor def */
return pseudo;
}
pseudo_t value_pseudo(long long val)
{
#define MAX_VAL_HASH 64
static struct pseudo_list *prev[MAX_VAL_HASH];
int hash = val & (MAX_VAL_HASH-1);
struct pseudo_list **list = prev + hash;
pseudo_t pseudo;
FOR_EACH_PTR(*list, pseudo) {
if (pseudo->value == val)
return pseudo;
} END_FOR_EACH_PTR(pseudo);
pseudo = __alloc_pseudo(0);
pseudo->type = PSEUDO_VAL;
pseudo->value = val;
add_pseudo(list, pseudo);
/* Value pseudos have neither nr, usage nor def */
return pseudo;
}
static pseudo_t argument_pseudo(struct entrypoint *ep, int nr)
{
pseudo_t pseudo = __alloc_pseudo(0);
struct instruction *entry = ep->entry;
pseudo->type = PSEUDO_ARG;
pseudo->nr = nr;
pseudo->def = entry;
add_pseudo(&entry->arg_list, pseudo);
/* Argument pseudos have neither usage nor def */
return pseudo;
}
pseudo_t alloc_phi(struct basic_block *source, pseudo_t pseudo, int size)
{
struct instruction *insn = alloc_instruction(OP_PHISOURCE, size);
pseudo_t phi = __alloc_pseudo(0);
static int nr = 0;
phi->type = PSEUDO_PHI;
phi->nr = ++nr;
phi->def = insn;
use_pseudo(insn, pseudo, &insn->phi_src);
insn->bb = source;
insn->target = phi;
add_instruction(&source->insns, insn);
return phi;
}
/*
* We carry the "access_data" structure around for any accesses,
* which simplifies things a lot. It contains all the access
* information in one place.
*/
struct access_data {
struct symbol *result_type; // result ctype
struct symbol *source_type; // source ctype
pseudo_t address; // pseudo containing address ..
pseudo_t origval; // pseudo for original value ..
unsigned int offset, alignment; // byte offset
unsigned int bit_size, bit_offset; // which bits
struct position pos;
};
static void finish_address_gen(struct entrypoint *ep, struct access_data *ad)
{
}
static int linearize_simple_address(struct entrypoint *ep,
struct expression *addr,
struct access_data *ad)
{
if (addr->type == EXPR_SYMBOL) {
linearize_one_symbol(ep, addr->symbol);
ad->address = symbol_pseudo(ep, addr->symbol);
return 1;
}
if (addr->type == EXPR_BINOP) {
if (addr->right->type == EXPR_VALUE) {
if (addr->op == '+') {
ad->offset += get_expression_value(addr->right);
return linearize_simple_address(ep, addr->left, ad);
}
}
}
ad->address = linearize_expression(ep, addr);
return 1;
}
static struct symbol *base_type(struct symbol *sym)
{
struct symbol *base = sym;
if (sym) {
if (sym->type == SYM_NODE)
base = base->ctype.base_type;
if (base->type == SYM_BITFIELD)
return base->ctype.base_type;
}
return sym;
}
static int linearize_address_gen(struct entrypoint *ep,
struct expression *expr,
struct access_data *ad)
{
struct symbol *ctype = expr->ctype;
if (!ctype)
return 0;
ad->pos = expr->pos;
ad->result_type = ctype;
ad->source_type = base_type(ctype);
ad->bit_size = ctype->bit_size;
ad->alignment = ctype->ctype.alignment;
ad->bit_offset = ctype->bit_offset;
if (expr->type == EXPR_PREOP && expr->op == '*')
return linearize_simple_address(ep, expr->unop, ad);
warning(expr->pos, "generating address of non-lvalue (%d)", expr->type);
return 0;
}
static pseudo_t add_load(struct entrypoint *ep, struct access_data *ad)
{
struct instruction *insn;
pseudo_t new;
new = ad->origval;
if (0 && new)
return new;
insn = alloc_typed_instruction(OP_LOAD, ad->source_type);
new = alloc_pseudo(insn);
ad->origval = new;
insn->target = new;
insn->offset = ad->offset;
use_pseudo(insn, ad->address, &insn->src);
add_one_insn(ep, insn);
return new;
}
static void add_store(struct entrypoint *ep, struct access_data *ad, pseudo_t value)
{
struct basic_block *bb = ep->active;
if (bb_reachable(bb)) {
struct instruction *store = alloc_typed_instruction(OP_STORE, ad->source_type);
store->offset = ad->offset;
use_pseudo(store, value, &store->target);
use_pseudo(store, ad->address, &store->src);
add_one_insn(ep, store);
}
}
static pseudo_t linearize_store_gen(struct entrypoint *ep,
pseudo_t value,
struct access_data *ad)
{
pseudo_t store = value;
if (type_size(ad->source_type) != type_size(ad->result_type)) {
pseudo_t orig = add_load(ep, ad);
int shift = ad->bit_offset;
unsigned long long mask = (1ULL << ad->bit_size)-1;
if (shift) {
store = add_binary_op(ep, ad->source_type, OP_SHL, value, value_pseudo(shift));
mask <<= shift;
}
orig = add_binary_op(ep, ad->source_type, OP_AND, orig, value_pseudo(~mask));
store = add_binary_op(ep, ad->source_type, OP_OR, orig, store);
}
add_store(ep, ad, store);
return value;
}
static pseudo_t add_binary_op(struct entrypoint *ep, struct symbol *ctype, int op, pseudo_t left, pseudo_t right)
{
struct instruction *insn = alloc_typed_instruction(op, ctype);
pseudo_t target = alloc_pseudo(insn);
insn->target = target;
use_pseudo(insn, left, &insn->src1);
use_pseudo(insn, right, &insn->src2);
add_one_insn(ep, insn);
return target;
}
static pseudo_t add_setval(struct entrypoint *ep, struct symbol *ctype, struct expression *val)
{
struct instruction *insn = alloc_typed_instruction(OP_SETVAL, ctype);
pseudo_t target = alloc_pseudo(insn);
insn->target = target;
insn->val = val;
add_one_insn(ep, insn);
return target;
}
static pseudo_t add_symbol_address(struct entrypoint *ep, struct symbol *sym)
{
struct instruction *insn = alloc_instruction(OP_SYMADDR, bits_in_pointer);
pseudo_t target = alloc_pseudo(insn);
insn->target = target;
use_pseudo(insn, symbol_pseudo(ep, sym), &insn->symbol);
add_one_insn(ep, insn);
return target;
}
static pseudo_t linearize_load_gen(struct entrypoint *ep, struct access_data *ad)
{
pseudo_t new = add_load(ep, ad);
if (ad->bit_offset) {
pseudo_t shift = value_pseudo(ad->bit_offset);
pseudo_t newval = add_binary_op(ep, ad->source_type, OP_LSR, new, shift);
new = newval;
}
return new;
}
static pseudo_t linearize_access(struct entrypoint *ep, struct expression *expr)
{
struct access_data ad = { NULL, };
pseudo_t value;
if (!linearize_address_gen(ep, expr, &ad))
return VOID;
value = linearize_load_gen(ep, &ad);
finish_address_gen(ep, &ad);
return value;
}
/* FIXME: FP */
static pseudo_t linearize_inc_dec(struct entrypoint *ep, struct expression *expr, int postop)
{
struct access_data ad = { NULL, };
pseudo_t old, new, one;
int op = expr->op == SPECIAL_INCREMENT ? OP_ADD : OP_SUB;
if (!linearize_address_gen(ep, expr->unop, &ad))
return VOID;
old = linearize_load_gen(ep, &ad);
one = value_pseudo(expr->op_value);
new = add_binary_op(ep, expr->ctype, op, old, one);
linearize_store_gen(ep, new, &ad);
finish_address_gen(ep, &ad);
return postop ? old : new;
}
static pseudo_t add_uniop(struct entrypoint *ep, struct expression *expr, int op, pseudo_t src)
{
struct instruction *insn = alloc_typed_instruction(op, expr->ctype);
pseudo_t new = alloc_pseudo(insn);
insn->target = new;
use_pseudo(insn, src, &insn->src1);
add_one_insn(ep, insn);
return new;
}
static pseudo_t linearize_slice(struct entrypoint *ep, struct expression *expr)
{
pseudo_t pre = linearize_expression(ep, expr->base);
struct instruction *insn = alloc_typed_instruction(OP_SLICE, expr->ctype);
pseudo_t new = alloc_pseudo(insn);
insn->target = new;
insn->from = expr->r_bitpos;
insn->len = expr->r_nrbits;
use_pseudo(insn, pre, &insn->base);
add_one_insn(ep, insn);
return new;
}
static pseudo_t linearize_regular_preop(struct entrypoint *ep, struct expression *expr)
{
pseudo_t pre = linearize_expression(ep, expr->unop);
switch (expr->op) {
case '+':
return pre;
case '!': {
pseudo_t zero = value_pseudo(0);
return add_binary_op(ep, expr->unop->ctype, OP_SET_EQ, pre, zero);
}
case '~':
return add_uniop(ep, expr, OP_NOT, pre);
case '-':
return add_uniop(ep, expr, OP_NEG, pre);
}
return VOID;
}
static pseudo_t linearize_preop(struct entrypoint *ep, struct expression *expr)
{
/*
* '*' is an lvalue access, and is fundamentally different
* from an arithmetic operation. Maybe it should have an
* expression type of its own..
*/
if (expr->op == '*')
return linearize_access(ep, expr);
if (expr->op == SPECIAL_INCREMENT || expr->op == SPECIAL_DECREMENT)
return linearize_inc_dec(ep, expr, 0);
return linearize_regular_preop(ep, expr);
}
static pseudo_t linearize_postop(struct entrypoint *ep, struct expression *expr)
{
return linearize_inc_dec(ep, expr, 1);
}
/*
* Casts to pointers are "less safe" than other casts, since
* they imply type-unsafe accesses. "void *" is a special
* case, since you can't access through it anyway without another
* cast.
*/
static struct instruction *alloc_cast_instruction(struct symbol *ctype)
{
int opcode = OP_CAST;
struct symbol *base = ctype;
if (base->ctype.modifiers & MOD_SIGNED)
opcode = OP_SCAST;
if (base->type == SYM_NODE)
base = base->ctype.base_type;
if (base->type == SYM_PTR) {
base = base->ctype.base_type;
if (base != &void_ctype)
opcode = OP_PTRCAST;
}
if (base->ctype.base_type == &fp_type)
opcode = OP_FPCAST;
return alloc_typed_instruction(opcode, ctype);
}
static pseudo_t cast_pseudo(struct entrypoint *ep, pseudo_t src, struct symbol *from, struct symbol *to)
{
pseudo_t result;
struct instruction *insn;
if (src == VOID)
return VOID;
if (!from || !to)
return VOID;
if (from->bit_size < 0 || to->bit_size < 0)
return VOID;
insn = alloc_cast_instruction(to);
result = alloc_pseudo(insn);
insn->target = result;
insn->orig_type = from;
use_pseudo(insn, src, &insn->src);
add_one_insn(ep, insn);
return result;
}
static int opcode_sign(int opcode, struct symbol *ctype)
{
if (ctype && (ctype->ctype.modifiers & MOD_SIGNED)) {
switch(opcode) {
case OP_MULU: case OP_DIVU: case OP_MODU: case OP_LSR:
opcode++;
}
}
return opcode;
}
static pseudo_t linearize_assignment(struct entrypoint *ep, struct expression *expr)
{
struct access_data ad = { NULL, };
struct expression *target = expr->left;
struct expression *src = expr->right;
pseudo_t value;
value = linearize_expression(ep, src);
if (!target || !linearize_address_gen(ep, target, &ad))
return value;
if (expr->op != '=') {
pseudo_t oldvalue = linearize_load_gen(ep, &ad);
pseudo_t dst;
static const int op_trans[] = {
[SPECIAL_ADD_ASSIGN - SPECIAL_BASE] = OP_ADD,
[SPECIAL_SUB_ASSIGN - SPECIAL_BASE] = OP_SUB,
[SPECIAL_MUL_ASSIGN - SPECIAL_BASE] = OP_MULU,
[SPECIAL_DIV_ASSIGN - SPECIAL_BASE] = OP_DIVU,
[SPECIAL_MOD_ASSIGN - SPECIAL_BASE] = OP_MODU,
[SPECIAL_SHL_ASSIGN - SPECIAL_BASE] = OP_SHL,
[SPECIAL_SHR_ASSIGN - SPECIAL_BASE] = OP_LSR,
[SPECIAL_AND_ASSIGN - SPECIAL_BASE] = OP_AND,
[SPECIAL_OR_ASSIGN - SPECIAL_BASE] = OP_OR,
[SPECIAL_XOR_ASSIGN - SPECIAL_BASE] = OP_XOR
};
int opcode;
if (!src)
return VOID;
oldvalue = cast_pseudo(ep, oldvalue, src->ctype, expr->ctype);
opcode = opcode_sign(op_trans[expr->op - SPECIAL_BASE], src->ctype);
dst = add_binary_op(ep, src->ctype, opcode, oldvalue, value);
value = cast_pseudo(ep, dst, expr->ctype, src->ctype);
}
value = linearize_store_gen(ep, value, &ad);
finish_address_gen(ep, &ad);
return value;
}
static pseudo_t linearize_call_expression(struct entrypoint *ep, struct expression *expr)
{
struct expression *arg, *fn;
struct instruction *insn = alloc_typed_instruction(OP_CALL, expr->ctype);
pseudo_t retval, call;
struct ctype *ctype = NULL;
struct context *context;
if (!expr->ctype) {
warning(expr->pos, "call with no type!");
return VOID;
}
FOR_EACH_PTR(expr->args, arg) {
pseudo_t new = linearize_expression(ep, arg);
use_pseudo(insn, new, add_pseudo(&insn->arguments, new));
} END_FOR_EACH_PTR(arg);
fn = expr->fn;
if (fn->ctype)
ctype = &fn->ctype->ctype;
if (fn->type == EXPR_PREOP) {
if (fn->unop->type == EXPR_SYMBOL) {
struct symbol *sym = fn->unop->symbol;
if (sym->ctype.base_type->type == SYM_FN)
fn = fn->unop;
}
}
if (fn->type == EXPR_SYMBOL) {
call = symbol_pseudo(ep, fn->symbol);
} else {
call = linearize_expression(ep, fn);
}
use_pseudo(insn, call, &insn->func);
retval = VOID;
if (expr->ctype != &void_ctype)
retval = alloc_pseudo(insn);
insn->target = retval;
add_one_insn(ep, insn);
if (ctype) {
FOR_EACH_PTR(ctype->contexts, context) {
int in = context->in;
int out = context->out;
int check = 0;
int context_diff;
if (in < 0) {
check = 1;
in = 0;
}
if (out < 0) {
check = 0;
out = 0;
}
context_diff = out - in;
if (check || context_diff) {
insn = alloc_instruction(OP_CONTEXT, 0);
insn->increment = context_diff;
insn->check = check;
insn->context_expr = context->context;
add_one_insn(ep, insn);
}
} END_FOR_EACH_PTR(context);
}
return retval;
}
static pseudo_t linearize_binop(struct entrypoint *ep, struct expression *expr)
{
pseudo_t src1, src2, dst;
static const int opcode[] = {
['+'] = OP_ADD, ['-'] = OP_SUB,
['*'] = OP_MULU, ['/'] = OP_DIVU,
['%'] = OP_MODU, ['&'] = OP_AND,
['|'] = OP_OR, ['^'] = OP_XOR,
[SPECIAL_LEFTSHIFT] = OP_SHL,
[SPECIAL_RIGHTSHIFT] = OP_LSR,
[SPECIAL_LOGICAL_AND] = OP_AND_BOOL,
[SPECIAL_LOGICAL_OR] = OP_OR_BOOL,
};
int op;
src1 = linearize_expression(ep, expr->left);
src2 = linearize_expression(ep, expr->right);
op = opcode_sign(opcode[expr->op], expr->ctype);
dst = add_binary_op(ep, expr->ctype, op, src1, src2);
return dst;
}
static pseudo_t linearize_logical_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false);
pseudo_t linearize_cond_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false);
static pseudo_t linearize_select(struct entrypoint *ep, struct expression *expr)
{
pseudo_t cond, true, false, res;
struct instruction *insn;
true = linearize_expression(ep, expr->cond_true);
false = linearize_expression(ep, expr->cond_false);
cond = linearize_expression(ep, expr->conditional);
insn = alloc_typed_instruction(OP_SEL, expr->ctype);
if (!expr->cond_true)
true = cond;
use_pseudo(insn, cond, &insn->src1);
use_pseudo(insn, true, &insn->src2);
use_pseudo(insn, false, &insn->src3);
res = alloc_pseudo(insn);
insn->target = res;
add_one_insn(ep, insn);
return res;
}
static pseudo_t add_join_conditional(struct entrypoint *ep, struct expression *expr,
pseudo_t phi1, pseudo_t phi2)
{
pseudo_t target;
struct instruction *phi_node;
if (phi1 == VOID)
return phi2;
if (phi2 == VOID)
return phi1;
phi_node = alloc_typed_instruction(OP_PHI, expr->ctype);
use_pseudo(phi_node, phi1, add_pseudo(&phi_node->phi_list, phi1));
use_pseudo(phi_node, phi2, add_pseudo(&phi_node->phi_list, phi2));
phi_node->target = target = alloc_pseudo(phi_node);
add_one_insn(ep, phi_node);
return target;
}
static pseudo_t linearize_short_conditional(struct entrypoint *ep, struct expression *expr,
struct expression *cond,
struct expression *expr_false)
{
pseudo_t src1, src2;
struct basic_block *bb_false;
struct basic_block *merge = alloc_basic_block(ep, expr->pos);
pseudo_t phi1, phi2;
int size = type_size(expr->ctype);
if (!expr_false || !ep->active)
return VOID;
bb_false = alloc_basic_block(ep, expr_false->pos);
src1 = linearize_expression(ep, cond);
phi1 = alloc_phi(ep->active, src1, size);
add_branch(ep, expr, src1, merge, bb_false);
set_activeblock(ep, bb_false);
src2 = linearize_expression(ep, expr_false);
phi2 = alloc_phi(ep->active, src2, size);
set_activeblock(ep, merge);
return add_join_conditional(ep, expr, phi1, phi2);
}
static pseudo_t linearize_conditional(struct entrypoint *ep, struct expression *expr,
struct expression *cond,
struct expression *expr_true,
struct expression *expr_false)
{
pseudo_t src1, src2;
pseudo_t phi1, phi2;
struct basic_block *bb_true, *bb_false, *merge;
int size = type_size(expr->ctype);
if (!cond || !expr_true || !expr_false || !ep->active)
return VOID;
bb_true = alloc_basic_block(ep, expr_true->pos);
bb_false = alloc_basic_block(ep, expr_false->pos);
merge = alloc_basic_block(ep, expr->pos);
linearize_cond_branch(ep, cond, bb_true, bb_false);
set_activeblock(ep, bb_true);
src1 = linearize_expression(ep, expr_true);
phi1 = alloc_phi(ep->active, src1, size);
add_goto(ep, merge);
set_activeblock(ep, bb_false);
src2 = linearize_expression(ep, expr_false);
phi2 = alloc_phi(ep->active, src2, size);
set_activeblock(ep, merge);
return add_join_conditional(ep, expr, phi1, phi2);
}
static pseudo_t linearize_logical(struct entrypoint *ep, struct expression *expr)
{
struct expression *shortcut;
shortcut = alloc_const_expression(expr->pos, expr->op == SPECIAL_LOGICAL_OR);
shortcut->ctype = expr->ctype;
return linearize_conditional(ep, expr, expr->left, shortcut, expr->right);
}
static pseudo_t linearize_compare(struct entrypoint *ep, struct expression *expr)
{
static const int cmpop[] = {
['>'] = OP_SET_GT, ['<'] = OP_SET_LT,
[SPECIAL_EQUAL] = OP_SET_EQ,
[SPECIAL_NOTEQUAL] = OP_SET_NE,
[SPECIAL_GTE] = OP_SET_GE,
[SPECIAL_LTE] = OP_SET_LE,
[SPECIAL_UNSIGNED_LT] = OP_SET_B,
[SPECIAL_UNSIGNED_GT] = OP_SET_A,
[SPECIAL_UNSIGNED_LTE] = OP_SET_BE,
[SPECIAL_UNSIGNED_GTE] = OP_SET_AE,
};
pseudo_t src1 = linearize_expression(ep, expr->left);
pseudo_t src2 = linearize_expression(ep, expr->right);
pseudo_t dst = add_binary_op(ep, expr->left->ctype, cmpop[expr->op], src1, src2);
return dst;
}
pseudo_t linearize_cond_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false)
{
pseudo_t cond;
if (!expr || !bb_reachable(ep->active))
return VOID;
switch (expr->type) {
case EXPR_STRING:
case EXPR_VALUE:
add_goto(ep, expr->value ? bb_true : bb_false);
return VOID;
case EXPR_FVALUE:
add_goto(ep, expr->fvalue ? bb_true : bb_false);
return VOID;
case EXPR_LOGICAL:
linearize_logical_branch(ep, expr, bb_true, bb_false);
return VOID;
case EXPR_COMPARE:
cond = linearize_compare(ep, expr);
add_branch(ep, expr, cond, bb_true, bb_false);
break;
case EXPR_PREOP:
if (expr->op == '!')
return linearize_cond_branch(ep, expr->unop, bb_false, bb_true);
/* fall through */
default: {
cond = linearize_expression(ep, expr);
add_branch(ep, expr, cond, bb_true, bb_false);
return VOID;
}
}
return VOID;
}
static pseudo_t linearize_logical_branch(struct entrypoint *ep, struct expression *expr, struct basic_block *bb_true, struct basic_block *bb_false)
{
struct basic_block *next = alloc_basic_block(ep, expr->pos);
if (expr->op == SPECIAL_LOGICAL_OR)
linearize_cond_branch(ep, expr->left, bb_true, next);
else
linearize_cond_branch(ep, expr->left, next, bb_false);
set_activeblock(ep, next);
linearize_cond_branch(ep, expr->right, bb_true, bb_false);
return VOID;
}
static pseudo_t linearize_cast(struct entrypoint *ep, struct expression *expr)
{
pseudo_t src;
struct expression *orig = expr->cast_expression;
if (!orig)
return VOID;
src = linearize_expression(ep, orig);
return cast_pseudo(ep, src, orig->ctype, expr->ctype);
}
static pseudo_t linearize_position(struct entrypoint *ep, struct expression *pos, struct access_data *ad)
{
struct expression *init_expr = pos->init_expr;
ad->offset = pos->init_offset;
ad->source_type = base_type(init_expr->ctype);
ad->result_type = init_expr->ctype;
return linearize_initializer(ep, init_expr, ad);
}
static pseudo_t linearize_initializer(struct entrypoint *ep, struct expression *initializer, struct access_data *ad)
{
switch (initializer->type) {
case EXPR_INITIALIZER: {
struct expression *expr;
FOR_EACH_PTR(initializer->expr_list, expr) {
linearize_initializer(ep, expr, ad);
} END_FOR_EACH_PTR(expr);
break;
}
case EXPR_POS:
linearize_position(ep, initializer, ad);
break;
default: {
pseudo_t value = linearize_expression(ep, initializer);
ad->source_type = base_type(initializer->ctype);
ad->result_type = initializer->ctype;
linearize_store_gen(ep, value, ad);
return value;
}
}
return VOID;
}
static void linearize_argument(struct entrypoint *ep, struct symbol *arg, int nr)
{
struct access_data ad = { NULL, };
ad.source_type = arg;
ad.result_type = arg;
ad.address = symbol_pseudo(ep, arg);
linearize_store_gen(ep, argument_pseudo(ep, nr), &ad);
finish_address_gen(ep, &ad);
}
pseudo_t linearize_expression(struct entrypoint *ep, struct expression *expr)
{
if (!expr)
return VOID;
current_pos = expr->pos;
switch (expr->type) {
case EXPR_SYMBOL:
linearize_one_symbol(ep, expr->symbol);
return add_symbol_address(ep, expr->symbol);
case EXPR_VALUE:
return value_pseudo(expr->value);
case EXPR_STRING: case EXPR_FVALUE: case EXPR_LABEL:
return add_setval(ep, expr->ctype, expr);
case EXPR_STATEMENT:
return linearize_statement(ep, expr->statement);
case EXPR_CALL:
return linearize_call_expression(ep, expr);
case EXPR_BINOP:
return linearize_binop(ep, expr);
case EXPR_LOGICAL:
return linearize_logical(ep, expr);
case EXPR_COMPARE:
return linearize_compare(ep, expr);
case EXPR_SELECT:
return linearize_select(ep, expr);
case EXPR_CONDITIONAL:
if (!expr->cond_true)
return linearize_short_conditional(ep, expr, expr->conditional, expr->cond_false);
return linearize_conditional(ep, expr, expr->conditional,
expr->cond_true, expr->cond_false);
case EXPR_COMMA:
linearize_expression(ep, expr->left);
return linearize_expression(ep, expr->right);
case EXPR_ASSIGNMENT:
return linearize_assignment(ep, expr);
case EXPR_PREOP:
return linearize_preop(ep, expr);
case EXPR_POSTOP:
return linearize_postop(ep, expr);
case EXPR_CAST:
case EXPR_FORCE_CAST:
case EXPR_IMPLIED_CAST:
return linearize_cast(ep, expr);
case EXPR_SLICE:
return linearize_slice(ep, expr);
case EXPR_INITIALIZER:
case EXPR_POS:
warning(expr->pos, "unexpected initializer expression (%d %d)", expr->type, expr->op);
return VOID;
default:
warning(expr->pos, "unknown expression (%d %d)", expr->type, expr->op);
return VOID;
}
return VOID;
}
static pseudo_t linearize_one_symbol(struct entrypoint *ep, struct symbol *sym)
{
struct access_data ad = { NULL, };
pseudo_t value;
if (!sym || !sym->initializer || sym->initialized)
return VOID;
/* We need to output these puppies some day too.. */
if (sym->ctype.modifiers & (MOD_STATIC | MOD_TOPLEVEL))
return VOID;
sym->initialized = 1;
ad.address = symbol_pseudo(ep, sym);
value = linearize_initializer(ep, sym->initializer, &ad);
finish_address_gen(ep, &ad);
return value;
}
static pseudo_t linearize_compound_statement(struct entrypoint *ep, struct statement *stmt)
{
pseudo_t pseudo;
struct statement *s;
struct symbol *ret = stmt->ret;
pseudo = VOID;
FOR_EACH_PTR(stmt->stmts, s) {
pseudo = linearize_statement(ep, s);
} END_FOR_EACH_PTR(s);
if (ret) {
struct basic_block *bb = add_label(ep, ret);
struct instruction *phi_node = first_instruction(bb->insns);
if (!phi_node)
return pseudo;
if (pseudo_list_size(phi_node->phi_list)==1) {
pseudo = first_pseudo(phi_node->phi_list);
assert(pseudo->type == PSEUDO_PHI);
return pseudo->def->src1;
}
return phi_node->target;
}
return pseudo;
}
static pseudo_t linearize_inlined_call(struct entrypoint *ep, struct statement *stmt)
{
struct instruction *insn = alloc_instruction(OP_INLINED_CALL, 0);
struct statement *args = stmt->args;
struct basic_block *bb;
pseudo_t pseudo;
if (args) {
struct symbol *sym;
concat_symbol_list(args->declaration, &ep->syms);
FOR_EACH_PTR(args->declaration, sym) {
pseudo_t value = linearize_one_symbol(ep, sym);
use_pseudo(insn, value, add_pseudo(&insn->arguments, value));
} END_FOR_EACH_PTR(sym);
}
insn->target = pseudo = linearize_compound_statement(ep, stmt);
use_pseudo(insn, symbol_pseudo(ep, stmt->inline_fn), &insn->func);
bb = ep->active;
if (bb && !bb->insns)
bb->pos = stmt->pos;
add_one_insn(ep, insn);
return pseudo;
}
static pseudo_t linearize_context(struct entrypoint *ep, struct statement *stmt)
{
struct instruction *insn = alloc_instruction(OP_CONTEXT, 0);
struct expression *expr = stmt->expression;
int value = 0;
if (expr->type == EXPR_VALUE)
value = expr->value;
insn->increment = value;
insn->context_expr = stmt->context;
add_one_insn(ep, insn);
return VOID;
}
static pseudo_t linearize_range(struct entrypoint *ep, struct statement *stmt)
{
struct instruction *insn = alloc_instruction(OP_RANGE, 0);
use_pseudo(insn, linearize_expression(ep, stmt->range_expression), &insn->src1);
use_pseudo(insn, linearize_expression(ep, stmt->range_low), &insn->src2);
use_pseudo(insn, linearize_expression(ep, stmt->range_high), &insn->src3);
add_one_insn(ep, insn);
return VOID;
}
ALLOCATOR(asm_rules, "asm rules");
ALLOCATOR(asm_constraint, "asm constraints");
static void add_asm_input(struct entrypoint *ep, struct instruction *insn, struct expression *expr,
const char *constraint, const struct ident *ident)
{
pseudo_t pseudo = linearize_expression(ep, expr);
struct asm_constraint *rule = __alloc_asm_constraint(0);
rule->ident = ident;
rule->constraint = constraint;
use_pseudo(insn, pseudo, &rule->pseudo);
add_ptr_list(&insn->asm_rules->inputs, rule);
}
static void add_asm_output(struct entrypoint *ep, struct instruction *insn, struct expression *expr,
const char *constraint, const struct ident *ident)
{
struct access_data ad = { NULL, };
pseudo_t pseudo = alloc_pseudo(insn);
struct asm_constraint *rule;
if (!expr || !linearize_address_gen(ep, expr, &ad))
return;
linearize_store_gen(ep, pseudo, &ad);
finish_address_gen(ep, &ad);
rule = __alloc_asm_constraint(0);
rule->ident = ident;
rule->constraint = constraint;
use_pseudo(insn, pseudo, &rule->pseudo);
add_ptr_list(&insn->asm_rules->outputs, rule);
}
static pseudo_t linearize_asm_statement(struct entrypoint *ep, struct statement *stmt)
{
int state;
struct expression *expr;
struct instruction *insn;
struct asm_rules *rules;
const char *constraint;
struct ident *ident;
insn = alloc_instruction(OP_ASM, 0);
expr = stmt->asm_string;
if (!expr || expr->type != EXPR_STRING) {
warning(stmt->pos, "expected string in inline asm");
return VOID;
}
insn->string = expr->string->data;
rules = __alloc_asm_rules(0);
insn->asm_rules = rules;
/* Gather the inputs.. */
state = 0;
ident = NULL;
constraint = NULL;
FOR_EACH_PTR(stmt->asm_inputs, expr) {
switch (state) {
case 0: /* Identifier */
state = 1;
ident = (struct ident *)expr;
continue;
case 1: /* Constraint */
state = 2;
constraint = expr ? expr->string->data : "";
continue;
case 2: /* Expression */
state = 0;
add_asm_input(ep, insn, expr, constraint, ident);
}
} END_FOR_EACH_PTR(expr);
add_one_insn(ep, insn);
/* Assign the outputs */
state = 0;
ident = NULL;
constraint = NULL;
FOR_EACH_PTR(stmt->asm_outputs, expr) {
switch (state) {
case 0: /* Identifier */
state = 1;
ident = (struct ident *)expr;
continue;
case 1: /* Constraint */
state = 2;
constraint = expr ? expr->string->data : "";
continue;
case 2:
state = 0;
add_asm_output(ep, insn, expr, constraint, ident);
}
} END_FOR_EACH_PTR(expr);
return VOID;
}
static int multijmp_cmp(const void *_a, const void *_b)
{
const struct multijmp *a = _a;
const struct multijmp *b = _b;
// "default" case?
if (a->begin > a->end) {
if (b->begin > b->end)
return 0;
return 1;
}
if (b->begin > b->end)
return -1;
if (a->begin == b->begin) {
if (a->end == b->end)
return 0;
return (a->end < b->end) ? -1 : 1;
}
return a->begin < b->begin ? -1 : 1;
}
static void sort_switch_cases(struct instruction *insn)
{
sort_list((struct ptr_list **)&insn->multijmp_list, multijmp_cmp);
}
static pseudo_t linearize_declaration(struct entrypoint *ep, struct statement *stmt)
{
struct symbol *sym;
concat_symbol_list(stmt->declaration, &ep->syms);
FOR_EACH_PTR(stmt->declaration, sym) {
linearize_one_symbol(ep, sym);
} END_FOR_EACH_PTR(sym);
return VOID;
}
pseudo_t linearize_statement(struct entrypoint *ep, struct statement *stmt)
{
struct basic_block *bb;
if (!stmt)
return VOID;
bb = ep->active;
if (bb && !bb->insns)
bb->pos = stmt->pos;
current_pos = stmt->pos;
switch (stmt->type) {
case STMT_NONE:
break;
case STMT_DECLARATION:
return linearize_declaration(ep, stmt);
case STMT_CONTEXT:
return linearize_context(ep, stmt);
case STMT_RANGE:
return linearize_range(ep, stmt);
case STMT_EXPRESSION:
return linearize_expression(ep, stmt->expression);
case STMT_ASM:
return linearize_asm_statement(ep, stmt);
case STMT_RETURN: {
struct expression *expr = stmt->expression;
struct basic_block *bb_return = get_bound_block(ep, stmt->ret_target);
struct basic_block *active;
pseudo_t src = linearize_expression(ep, expr);
active = ep->active;
if (active && src != &void_pseudo) {
struct instruction *phi_node = first_instruction(bb_return->insns);
pseudo_t phi;
if (!phi_node) {
phi_node = alloc_typed_instruction(OP_PHI, expr->ctype);
phi_node->target = alloc_pseudo(phi_node);
phi_node->bb = bb_return;
add_instruction(&bb_return->insns, phi_node);
}
phi = alloc_phi(active, src, type_size(expr->ctype));
phi->ident = &return_ident;
use_pseudo(phi_node, phi, add_pseudo(&phi_node->phi_list, phi));
}
add_goto(ep, bb_return);
return VOID;
}
case STMT_CASE: {
add_label(ep, stmt->case_label);
linearize_statement(ep, stmt->case_statement);
break;
}
case STMT_LABEL: {
struct symbol *label = stmt->label_identifier;
if (label->used) {
add_label(ep, label);
linearize_statement(ep, stmt->label_statement);
}
break;
}
case STMT_GOTO: {
struct symbol *sym;
struct expression *expr;
struct instruction *goto_ins;
struct basic_block *active;
pseudo_t pseudo;
active = ep->active;
if (!bb_reachable(active))
break;
if (stmt->goto_label) {
add_goto(ep, get_bound_block(ep, stmt->goto_label));
break;
}
expr = stmt->goto_expression;
if (!expr)
break;
/* This can happen as part of simplification */
if (expr->type == EXPR_LABEL) {
add_goto(ep, get_bound_block(ep, expr->label_symbol));
break;
}
pseudo = linearize_expression(ep, expr);
goto_ins = alloc_instruction(OP_COMPUTEDGOTO, 0);
use_pseudo(goto_ins, pseudo, &goto_ins->target);
add_one_insn(ep, goto_ins);
FOR_EACH_PTR(stmt->target_list, sym) {
struct basic_block *bb_computed = get_bound_block(ep, sym);
struct multijmp *jmp = alloc_multijmp(bb_computed, 1, 0);
add_multijmp(&goto_ins->multijmp_list, jmp);
add_bb(&bb_computed->parents, ep->active);
add_bb(&active->children, bb_computed);
} END_FOR_EACH_PTR(sym);
finish_block(ep);
break;
}
case STMT_COMPOUND:
if (stmt->inline_fn)
return linearize_inlined_call(ep, stmt);
return linearize_compound_statement(ep, stmt);
/*
* This could take 'likely/unlikely' into account, and
* switch the arms around appropriately..
*/
case STMT_IF: {
struct basic_block *bb_true, *bb_false, *endif;
struct expression *cond = stmt->if_conditional;
bb_true = alloc_basic_block(ep, stmt->pos);
bb_false = endif = alloc_basic_block(ep, stmt->pos);
linearize_cond_branch(ep, cond, bb_true, bb_false);
set_activeblock(ep, bb_true);
linearize_statement(ep, stmt->if_true);
if (stmt->if_false) {
endif = alloc_basic_block(ep, stmt->pos);
add_goto(ep, endif);
set_activeblock(ep, bb_false);
linearize_statement(ep, stmt->if_false);
}
set_activeblock(ep, endif);
break;
}
case STMT_SWITCH: {
struct symbol *sym;
struct instruction *switch_ins;
struct basic_block *switch_end = alloc_basic_block(ep, stmt->pos);
struct basic_block *active, *default_case;
struct multijmp *jmp;
pseudo_t pseudo;
pseudo = linearize_expression(ep, stmt->switch_expression);
active = ep->active;
if (!bb_reachable(active))
break;
switch_ins = alloc_instruction(OP_SWITCH, 0);
use_pseudo(switch_ins, pseudo, &switch_ins->cond);
add_one_insn(ep, switch_ins);
finish_block(ep);
default_case = NULL;
FOR_EACH_PTR(stmt->switch_case->symbol_list, sym) {
struct statement *case_stmt = sym->stmt;
struct basic_block *bb_case = get_bound_block(ep, sym);
if (!case_stmt->case_expression) {
default_case = bb_case;
continue;
} else {
int begin, end;
begin = end = case_stmt->case_expression->value;
if (case_stmt->case_to)
end = case_stmt->case_to->value;
if (begin > end)
jmp = alloc_multijmp(bb_case, end, begin);
else
jmp = alloc_multijmp(bb_case, begin, end);
}
add_multijmp(&switch_ins->multijmp_list, jmp);
add_bb(&bb_case->parents, active);
add_bb(&active->children, bb_case);
} END_FOR_EACH_PTR(sym);
bind_label(stmt->switch_break, switch_end, stmt->pos);
/* And linearize the actual statement */
linearize_statement(ep, stmt->switch_statement);
set_activeblock(ep, switch_end);
if (!default_case)
default_case = switch_end;
jmp = alloc_multijmp(default_case, 1, 0);
add_multijmp(&switch_ins->multijmp_list, jmp);
add_bb(&default_case->parents, active);
add_bb(&active->children, default_case);
sort_switch_cases(switch_ins);
break;
}
case STMT_ITERATOR: {
struct statement *pre_statement = stmt->iterator_pre_statement;
struct expression *pre_condition = stmt->iterator_pre_condition;
struct statement *statement = stmt->iterator_statement;
struct statement *post_statement = stmt->iterator_post_statement;
struct expression *post_condition = stmt->iterator_post_condition;
struct basic_block *loop_top, *loop_body, *loop_continue, *loop_end;
concat_symbol_list(stmt->iterator_syms, &ep->syms);
linearize_statement(ep, pre_statement);
loop_body = loop_top = alloc_basic_block(ep, stmt->pos);
loop_continue = alloc_basic_block(ep, stmt->pos);
loop_end = alloc_basic_block(ep, stmt->pos);
/* An empty post-condition means that it's the same as the pre-condition */
if (!post_condition) {
loop_top = alloc_basic_block(ep, stmt->pos);
set_activeblock(ep, loop_top);
}
if (pre_condition)
linearize_cond_branch(ep, pre_condition, loop_body, loop_end);
bind_label(stmt->iterator_continue, loop_continue, stmt->pos);
bind_label(stmt->iterator_break, loop_end, stmt->pos);
set_activeblock(ep, loop_body);
linearize_statement(ep, statement);
add_goto(ep, loop_continue);
set_activeblock(ep, loop_continue);
linearize_statement(ep, post_statement);
if (!post_condition)
add_goto(ep, loop_top);
else
linearize_cond_branch(ep, post_condition, loop_top, loop_end);
set_activeblock(ep, loop_end);
break;
}
default:
break;
}
return VOID;
}
static struct entrypoint *linearize_fn(struct symbol *sym, struct symbol *base_type)
{
struct entrypoint *ep;
struct basic_block *bb;
struct symbol *arg;
struct instruction *entry;
pseudo_t result;
int i;
if (!base_type->stmt)
return NULL;
ep = alloc_entrypoint();
bb = alloc_basic_block(ep, sym->pos);
ep->name = sym;
sym->ep = ep;
set_activeblock(ep, bb);
entry = alloc_instruction(OP_ENTRY, 0);
add_one_insn(ep, entry);
ep->entry = entry;
concat_symbol_list(base_type->arguments, &ep->syms);
/* FIXME!! We should do something else about varargs.. */
i = 0;
FOR_EACH_PTR(base_type->arguments, arg) {
linearize_argument(ep, arg, ++i);
} END_FOR_EACH_PTR(arg);
result = linearize_statement(ep, base_type->stmt);
if (bb_reachable(ep->active) && !bb_terminated(ep->active)) {
struct symbol *ret_type = base_type->ctype.base_type;
struct instruction *insn = alloc_typed_instruction(OP_RET, ret_type);
if (type_size(ret_type) > 0)
use_pseudo(insn, result, &insn->src);
add_one_insn(ep, insn);
}
/*
* Do trivial flow simplification - branches to
* branches, kill dead basicblocks etc
*/
kill_unreachable_bbs(ep);
/*
* Turn symbols into pseudos
*/
simplify_symbol_usage(ep);
repeat:
/*
* Remove trivial instructions, and try to CSE
* the rest.
*/
do {
cleanup_and_cse(ep);
pack_basic_blocks(ep);
} while (repeat_phase & REPEAT_CSE);
kill_unreachable_bbs(ep);
vrfy_flow(ep);
/* Cleanup */
clear_symbol_pseudos(ep);
/* And track pseudo register usage */
track_pseudo_liveness(ep);
/*
* Some flow optimizations can only effectively
* be done when we've done liveness analysis. But
* if they trigger, we need to start all over
* again
*/
if (simplify_flow(ep)) {
clear_liveness(ep);
goto repeat;
}
/* Finally, add deathnotes to pseudos now that we have them */
if (dbg_dead)
track_pseudo_death(ep);
return ep;
}
struct entrypoint *linearize_symbol(struct symbol *sym)
{
struct symbol *base_type;
if (!sym)
return NULL;
current_pos = sym->pos;
base_type = sym->ctype.base_type;
if (!base_type)
return NULL;
if (base_type->type == SYM_FN)
return linearize_fn(sym, base_type);
return NULL;
}