//Check and replace 'exp' with 'cand_expr' if they are
//equal, and update SSA info. If 'cand_expr' is NOT leaf,
//that will create redundant computation, and
//depends on later Redundancy Elimination to reverse back.
//
//'cand_expr': substitute cand_expr for exp.
// e.g: exp is pr1 of S2, cand_expr is 10.
// pr1 = 10 //S1
// g = pr1 //S2
// =>
// pr1 = 10
// g = 10
//
//NOTE: Do NOT handle stmt.
void IR_CP::replaceExpViaSSADu(IR * exp, IR const* cand_expr,
IN OUT CPCtx & ctx)
{
ASSERT0(exp && exp->is_exp() && cand_expr && cand_expr->is_exp());
ASSERT0(exp->get_exact_ref());
if (!checkTypeConsistency(exp, cand_expr)) {
return;
}
IR * parent = IR_parent(exp);
if (parent->is_ild()) {
CPC_need_recomp_aa(ctx) = true;
} else if (parent->is_ist() && exp == IST_base(parent)) {
if (!cand_expr->is_ld() &&
!cand_expr->is_pr() &&
!cand_expr->is_lda()) {
return;
}
CPC_need_recomp_aa(ctx) = true;
}
IR * newir = m_ru->dupIRTree(cand_expr);
if (cand_expr->is_read_pr() && PR_ssainfo(cand_expr) != NULL) {
PR_ssainfo(newir) = PR_ssainfo(cand_expr);
SSA_uses(PR_ssainfo(newir)).append(newir);
} else {
m_du->copyIRTreeDU(newir, cand_expr, true);
}
//cand_expr may be IR tree. And there might be PR or LD on the tree.
newir->copyRefForTree(cand_expr, m_ru);
//Add SSA use for new exp.
SSAInfo * cand_ssainfo = NULL;
if ((cand_ssainfo = cand_expr->get_ssainfo()) != NULL) {
SSA_uses(cand_ssainfo).append(newir);
}
//Remove old exp SSA use.
SSAInfo * exp_ssainfo = exp->get_ssainfo();
ASSERT0(exp_ssainfo);
ASSERT0(SSA_uses(exp_ssainfo).find(exp));
SSA_uses(exp_ssainfo).remove(exp);
CPC_change(ctx) = true;
ASSERT0(exp->get_stmt());
bool doit = parent->replaceKid(exp, newir, false);
ASSERT0(doit);
UNUSED(doit);
m_ru->freeIRTree(exp);
}
//Check and replace 'ir' with 'cand_expr' if they are
//equal, and update DU info. If 'cand_expr' is NOT leaf,
//that will create redundant computation, and
//depends on later Redundancy Elimination to reverse back.
//exp: expression which will be replaced.
//
//cand_expr: substitute cand_expr for exp.
// e.g: cand_expr is *p, cand_expr_md is MD3
// *p(MD3) = 10 //p point to MD3
// ...
// g = *q(MD3) //q point to MD3
//
//exp_use_ssadu: true if exp used SSA du info.
//
//NOTE: Do NOT handle stmt.
void IR_CP::replaceExp(IR * exp, IR const* cand_expr,
IN OUT CPCtx & ctx, bool exp_use_ssadu)
{
ASSERT0(exp && exp->is_exp() && cand_expr);
ASSERT0(exp->get_exact_ref());
if (!checkTypeConsistency(exp, cand_expr)) {
return;
}
IR * parent = IR_parent(exp);
if (parent->is_ild()) {
CPC_need_recomp_aa(ctx) = true;
} else if (parent->is_ist() && exp == IST_base(parent)) {
if (!cand_expr->is_ld() && !cand_expr->is_pr() && !cand_expr->is_lda()) {
return;
}
CPC_need_recomp_aa(ctx) = true;
}
IR * newir = m_ru->dupIRTree(cand_expr);
m_du->copyIRTreeDU(newir, cand_expr, true);
ASSERT0(cand_expr->get_stmt());
if (exp_use_ssadu) {
//Remove exp SSA use.
ASSERT0(exp->get_ssainfo());
ASSERT0(exp->get_ssainfo()->get_uses().find(exp));
exp->removeSSAUse();
} else {
m_du->removeUseOutFromDefset(exp);
}
CPC_change(ctx) = true;
ASSERT0(exp->get_stmt());
bool doit = parent->replaceKid(exp, newir, false);
ASSERT0(doit);
UNUSED(doit);
m_ru->freeIRTree(exp);
}
//The followed forms
// x is signed
// IF(x > 0x7FFFFFFF) {a=1} ELSE {b=1} => b=1
// IF(x < 0x80000000) {a=1} ELSE {b=1} => b=1
//
// x is unsigned
// IF(x > 0xFFFFFFFF){a=1} ELSE {b=1} => b=1
// IF(x < 0x0) {a=1} ELSE {b=1} => b=1
bool IR_CFS_OPT::transformIf3(IR ** head, IR * ir)
{
ASSERT(head && *head, ("invalid parameter"));
if (ir == NULL || !ir->is_if()) { return false; }
IR * det = IF_det(ir);
if (det->is_gt()) {
IR * opnd0 = BIN_opnd0(det);
IR * opnd1 = BIN_opnd1(det);
if (opnd0->is_ld() &&
opnd0->is_int() &&
opnd1->is_const() &&
opnd1->is_int() &&
m_ru->getIntegerInDataTypeValueRange(opnd1) ==
m_ru->getMaxInteger(m_tm->get_dtype_bitsize(
TY_dtype(opnd1->get_type())), opnd1->is_signed())) {
//e.g:
//x is unsigned, if(x>0xFFFFFFFF) {a=1} else {b=1} => b=1
//x is signed, if(x>0x7FFFFFFF) {a=1} else {b=1} => b=1
IR * allocIR = NULL;
if (IF_falsebody(ir) != NULL) {
allocIR = m_ru->dupIRTree(IF_falsebody(ir));
}
xcom::replace(head, ir, allocIR);
if (allocIR != NULL) {
IR_parent(allocIR) = IR_parent(ir);
}
m_ru->freeIRTree(ir);
return true;
}
} else if (det->is_lt()) {
IR * opnd0 = BIN_opnd0(det);
IR * opnd1 = BIN_opnd1(det);
if (opnd0->is_ld() &&
opnd0->is_int() &&
opnd1->is_const() &&
opnd1->is_int() &&
m_ru->getIntegerInDataTypeValueRange(opnd1) ==
m_ru->getMinInteger(m_tm->get_dtype_bitsize(
TY_dtype(opnd1->get_type())), opnd1->is_signed())) {
//x is signed, IF(x < 0x80000000) {a=1} ELSE {b=1} => b=1
IR * allocIR = NULL;
if (IF_falsebody(ir) != NULL) {
allocIR = m_ru->dupIRTree(IF_falsebody(ir));
}
xcom::replace(head, ir, allocIR);
if (allocIR != NULL) {
IR_parent(allocIR) = IR_parent(ir);
}
m_ru->freeIRTree(ir);
return true;
} else if (opnd0->is_ld() &&
opnd1->is_const() &&
opnd0->is_uint() &&
CONST_int_val(opnd1) == 0) {
//x is unsigned, if(x<0) {a=1} else {b=1} => b=1
IR * allocIR = NULL;
if (IF_falsebody(ir) != NULL) {
allocIR = m_ru->dupIRTree(IF_falsebody(ir));
}
xcom::replace(head, ir, allocIR);
if (allocIR != NULL) {
IR_parent(allocIR) = IR_parent(ir);
}
m_ru->freeIRTree(ir);
return true;
}
}
return false;
}
//The followed forms
// if (cond) {
// t=1
// a=1
// goto L1;
// }
// f=1
// goto L2;
// L1:
//
//is replaced with
//
// if (!cond) {
// f=1
// goto L2;
// }
// t=1
// a=1
// L1:
//
//'goto L1' is removed and free, and L1 is removed if it is not a target
//of some other instruction.
bool IR_CFS_OPT::transformIf1(IR ** head, IR * ir)
{
ASSERT(head && *head, ("invalid parameter"));
if (ir == NULL || !ir->is_if()) { return false; }
//Check true part.
IR * t = IF_truebody(ir);
while (t != NULL) {
if (!is_non_branch_ir(t)) {
break;
}
t = t->get_next();
}
if (t != NULL && t->get_next() == NULL && t->is_goto()) {
IR * first_goto = t;
t = ir->get_next();
while (t != NULL) {
if (!is_non_branch_ir(t)) { break; }
t = t->get_next();
}
if (t != NULL && t->is_goto()) {
IR * second_goto = t;
if (IR_next(second_goto) != NULL &&
IR_next(second_goto)->is_lab() &&
isSameLabel(GOTO_lab(first_goto),
LAB_lab(IR_next(second_goto)))) {
//Start transforming.
m_ru->invertCondition(&IF_det(ir));
IR * new_list1 = NULL;
IR * new_list2 = NULL;
t = IF_truebody(ir);
//Split true body of IF.
IR * last = NULL;
while (t != first_goto) {
IR * c = t;
t = t->get_next();
xcom::remove(&IF_truebody(ir), c);
xcom::add_next(&new_list1, &last, c);
}
ASSERT(t && t == first_goto, ("invalid control flow"));
xcom::remove(&IF_truebody(ir), first_goto);
m_ru->freeIRTree(first_goto);
//Split all irs between IF and L1.
t = ir->get_next();
while (t != second_goto) {
IR * c = t;
t = t->get_next();
xcom::remove(head, c);
xcom::add_next(&new_list2, c);
}
ASSERT(t != NULL && t == second_goto, ("???"));
xcom::remove(head, second_goto);
xcom::add_next(&new_list2, second_goto);
//Swap new_list1 and new_list2
xcom::insertbefore(&IF_truebody(ir), IF_truebody(ir), new_list2);
//Update the IR_parent for new_list2.
for (IR * tmp = new_list2; tmp != NULL; tmp = IR_next(tmp)) {
IR_parent(tmp) = ir;
}
ASSERT(IF_truebody(ir) == new_list2, ("illegal insertbefore<T>"));
xcom::insertafter(&ir, new_list1);
//Update the IR_parent for new_list1.
for (IR * tmp = new_list1; tmp != NULL; tmp = IR_next(tmp)) {
IR_parent(tmp) = IR_parent(ir);
}
return true;
}
}
}
return false;
}
/* The followed forms
x is signed
IF(x > 0x7FFFFFFF) {a=1} ELSE {b=1} => b=1
IF(x < 0x80000000) {a=1} ELSE {b=1} => b=1
x is unsigned
IF(x > 0xFFFFFFFF){a=1} ELSE {b=1} => b=1
IF(x < 0x0) {a=1} ELSE {b=1} => b=1 */
bool IR_CFS_OPT::trans_if3(IR ** head, IR * ir)
{
IS_TRUE(head && *head, ("invalid parameter"));
if (ir == NULL || IR_type(ir) != IR_IF) { return false; }
IR * det = IF_det(ir);
if (IR_type(det) == IR_GT) {
IR * opnd0 = BIN_opnd0(det);
IR * opnd1 = BIN_opnd1(det);
DTD const* op0_rty = opnd0->get_dtd(m_dm);
DTD const* op1_rty = opnd1->get_dtd(m_dm);
if (IR_type(opnd0) == IR_LD &&
opnd1->is_const() &&
opnd0->is_int(m_dm) &&
CONST_int_val(opnd1) == MAX_INT_VALUE) {
//x is signed, if(x>0x7FFFFFFF) {a=1} else {b=1} => b=1
IR * new_ir = NULL;
if (IF_falsebody(ir)) {
new_ir = m_ru->dup_irs(IF_falsebody(ir));
}
replace(head, ir, new_ir);
//Revise IR_parent.
IR_parent(new_ir) = IR_parent(ir);
m_ru->free_irs(ir);
return true;
} else if (IR_type(opnd0) == IR_LD &&
IR_is_const(opnd1) &&
opnd0->is_uint(m_dm) &&
CONST_int_val(opnd1) == MAX_UINT_VALUE) {
//x is unsigned, if(x>0xFFFFFFFF) {a=1} else {b=1} => b=1
IR * new_ir = NULL;
if (IF_falsebody(ir)) {
new_ir = m_ru->dup_irs(IF_falsebody(ir));
}
replace(head, ir, new_ir);
//Revise IR_parent.
IR_parent(new_ir) = IR_parent(ir);
m_ru->free_irs(ir);
return true;
}
} else if (IR_type(det) == IR_LT) {
IR * opnd0 = BIN_opnd0(det);
IR * opnd1 = BIN_opnd1(det);
DTD const* op0_rty = opnd0->get_dtd(m_dm);
DTD const* op1_rty = opnd1->get_dtd(m_dm);
if (IR_type(opnd0) == IR_LD &&
IR_is_const(opnd1) &&
opnd0->is_int(m_dm) &&
CONST_int_val(opnd1) == MIN_INT_VALUE) {
//x is signed, IF(x < 0x80000000) {a=1} ELSE {b=1} => b=1
IR * new_ir = NULL;
if (IF_falsebody(ir)) {
new_ir = m_ru->dup_irs(IF_falsebody(ir));
}
replace(head, ir, new_ir);
m_ru->free_irs(ir);
return true;
} else if (IR_type(opnd0) == IR_LD &&
IR_is_const(opnd1) &&
opnd0->is_uint(m_dm) &&
CONST_int_val(opnd1) == 0) {
//x is unsigned, if(x<0) {a=1} else {b=1} => b=1
IR * new_ir = NULL;
if (IF_falsebody(ir)) {
new_ir = m_ru->dup_irs(IF_falsebody(ir));
}
replace(head, ir, new_ir);
//Revise IR_parent.
IR_parent(new_ir) = IR_parent(ir);
m_ru->free_irs(ir);
return true;
}
}
return false;
}
/* The followed forms
if (cond) {
t=1
a=1
goto L1;
}
f=1
goto L2;
L1:
is replaced by
if (!cond) {
f=1
goto L2;
}
t=1
a=1
L1:
'goto L1' is removed and free, and L1 is removed if it is not a target
of some other instruction. */
bool IR_CFS_OPT::trans_if1(IR ** head, IR * ir)
{
IS_TRUE(head && *head, ("invalid parameter"));
if (ir == NULL || IR_type(ir) != IR_IF) { return false; }
//Check true part.
IR * t = IF_truebody(ir);
while (t != NULL) {
if (!is_non_branch_ir(t)) {
break;
}
t = IR_next(t);
}
if (t != NULL && IR_next(t) == NULL && IR_type(t) == IR_GOTO) {
IR * first_goto = t;
t = IR_next(ir);
while (t != NULL) {
if (!is_non_branch_ir(t)) break;
t = IR_next(t);
}
if (t != NULL && IR_type(t) == IR_GOTO) {
IR * second_goto = t;
if (IR_next(second_goto) != NULL &&
IR_next(second_goto)->is_lab() &&
is_same_label(GOTO_lab(first_goto),
LAB_lab(IR_next(second_goto)))) {
//Here we start to transform...
m_ru->invert_cond(&IF_det(ir));
IR * new_list1 = NULL;
IR * new_list2 = NULL;
t = IF_truebody(ir);
//Split true body of IF.
IR * last = NULL;
while (t != first_goto) {
IR * c = t;
t = IR_next(t);
remove(&IF_truebody(ir), c);
add_next(&new_list1, &last, c);
}
IS_TRUE(t && t == first_goto, ("invalid control flow"));
remove(&IF_truebody(ir), first_goto);
m_ru->free_irs(first_goto);
//Split all irs between IF and L1.
t = IR_next(ir);
while (t != second_goto) {
IR * c = t;
t = IR_next(t);
remove(head, c);
add_next(&new_list2, c);
}
IS_TRUE(t != NULL && t == second_goto, ("???"));
remove(head, second_goto);
add_next(&new_list2, second_goto);
//Swap new_list1 and new_list2
insertbefore(&IF_truebody(ir), IF_truebody(ir), new_list2);
//Update the IR_parent for new_list2.
for (IR * tmp = new_list2; tmp != NULL; tmp = IR_next(tmp)) {
IR_parent(tmp) = ir;
}
IS_TRUE(IF_truebody(ir) == new_list2,
("illegal insertbefore<T>"));
insertafter(&ir, new_list1);
//Update the IR_parent for new_list1.
for (IR * tmp = new_list1; tmp != NULL; tmp = IR_next(tmp)) {
IR_parent(tmp) = IR_parent(ir);
}
return true;
}
}
}
return false;
}
