1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/c1/c1_Canonicalizer.cpp Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,945 @@
1.4 +/*
1.5 + * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#include "precompiled.hpp"
1.29 +#include "c1/c1_Canonicalizer.hpp"
1.30 +#include "c1/c1_InstructionPrinter.hpp"
1.31 +#include "c1/c1_ValueStack.hpp"
1.32 +#include "ci/ciArray.hpp"
1.33 +#include "runtime/sharedRuntime.hpp"
1.34 +
1.35 +
1.36 +class PrintValueVisitor: public ValueVisitor {
1.37 + void visit(Value* vp) {
1.38 + (*vp)->print_line();
1.39 + }
1.40 +};
1.41 +
1.42 +void Canonicalizer::set_canonical(Value x) {
1.43 + assert(x != NULL, "value must exist");
1.44 + // Note: we can not currently substitute root nodes which show up in
1.45 + // the instruction stream (because the instruction list is embedded
1.46 + // in the instructions).
1.47 + if (canonical() != x) {
1.48 +#ifndef PRODUCT
1.49 + if (!x->has_printable_bci()) {
1.50 + x->set_printable_bci(bci());
1.51 + }
1.52 +#endif
1.53 + if (PrintCanonicalization) {
1.54 + PrintValueVisitor do_print_value;
1.55 + canonical()->input_values_do(&do_print_value);
1.56 + canonical()->print_line();
1.57 + tty->print_cr("canonicalized to:");
1.58 + x->input_values_do(&do_print_value);
1.59 + x->print_line();
1.60 + tty->cr();
1.61 + }
1.62 + assert(_canonical->type()->tag() == x->type()->tag(), "types must match");
1.63 + _canonical = x;
1.64 + }
1.65 +}
1.66 +
1.67 +
1.68 +void Canonicalizer::move_const_to_right(Op2* x) {
1.69 + if (x->x()->type()->is_constant() && x->is_commutative()) x->swap_operands();
1.70 +}
1.71 +
1.72 +
1.73 +void Canonicalizer::do_Op2(Op2* x) {
1.74 + if (x->x() == x->y()) {
1.75 + switch (x->op()) {
1.76 + case Bytecodes::_isub: set_constant(0); return;
1.77 + case Bytecodes::_lsub: set_constant(jlong_cast(0)); return;
1.78 + case Bytecodes::_iand: // fall through
1.79 + case Bytecodes::_land: // fall through
1.80 + case Bytecodes::_ior: // fall through
1.81 + case Bytecodes::_lor : set_canonical(x->x()); return;
1.82 + case Bytecodes::_ixor: set_constant(0); return;
1.83 + case Bytecodes::_lxor: set_constant(jlong_cast(0)); return;
1.84 + }
1.85 + }
1.86 +
1.87 + if (x->x()->type()->is_constant() && x->y()->type()->is_constant()) {
1.88 + // do constant folding for selected operations
1.89 + switch (x->type()->tag()) {
1.90 + case intTag:
1.91 + { jint a = x->x()->type()->as_IntConstant()->value();
1.92 + jint b = x->y()->type()->as_IntConstant()->value();
1.93 + switch (x->op()) {
1.94 + case Bytecodes::_iadd: set_constant(a + b); return;
1.95 + case Bytecodes::_isub: set_constant(a - b); return;
1.96 + case Bytecodes::_imul: set_constant(a * b); return;
1.97 + case Bytecodes::_idiv:
1.98 + if (b != 0) {
1.99 + if (a == min_jint && b == -1) {
1.100 + set_constant(min_jint);
1.101 + } else {
1.102 + set_constant(a / b);
1.103 + }
1.104 + return;
1.105 + }
1.106 + break;
1.107 + case Bytecodes::_irem:
1.108 + if (b != 0) {
1.109 + if (a == min_jint && b == -1) {
1.110 + set_constant(0);
1.111 + } else {
1.112 + set_constant(a % b);
1.113 + }
1.114 + return;
1.115 + }
1.116 + break;
1.117 + case Bytecodes::_iand: set_constant(a & b); return;
1.118 + case Bytecodes::_ior : set_constant(a | b); return;
1.119 + case Bytecodes::_ixor: set_constant(a ^ b); return;
1.120 + }
1.121 + }
1.122 + break;
1.123 + case longTag:
1.124 + { jlong a = x->x()->type()->as_LongConstant()->value();
1.125 + jlong b = x->y()->type()->as_LongConstant()->value();
1.126 + switch (x->op()) {
1.127 + case Bytecodes::_ladd: set_constant(a + b); return;
1.128 + case Bytecodes::_lsub: set_constant(a - b); return;
1.129 + case Bytecodes::_lmul: set_constant(a * b); return;
1.130 + case Bytecodes::_ldiv:
1.131 + if (b != 0) {
1.132 + set_constant(SharedRuntime::ldiv(b, a));
1.133 + return;
1.134 + }
1.135 + break;
1.136 + case Bytecodes::_lrem:
1.137 + if (b != 0) {
1.138 + set_constant(SharedRuntime::lrem(b, a));
1.139 + return;
1.140 + }
1.141 + break;
1.142 + case Bytecodes::_land: set_constant(a & b); return;
1.143 + case Bytecodes::_lor : set_constant(a | b); return;
1.144 + case Bytecodes::_lxor: set_constant(a ^ b); return;
1.145 + }
1.146 + }
1.147 + break;
1.148 + // other cases not implemented (must be extremely careful with floats & doubles!)
1.149 + }
1.150 + }
1.151 + // make sure constant is on the right side, if any
1.152 + move_const_to_right(x);
1.153 +
1.154 + if (x->y()->type()->is_constant()) {
1.155 + // do constant folding for selected operations
1.156 + switch (x->type()->tag()) {
1.157 + case intTag:
1.158 + if (x->y()->type()->as_IntConstant()->value() == 0) {
1.159 + switch (x->op()) {
1.160 + case Bytecodes::_iadd: set_canonical(x->x()); return;
1.161 + case Bytecodes::_isub: set_canonical(x->x()); return;
1.162 + case Bytecodes::_imul: set_constant(0); return;
1.163 + // Note: for div and rem, make sure that C semantics
1.164 + // corresponds to Java semantics!
1.165 + case Bytecodes::_iand: set_constant(0); return;
1.166 + case Bytecodes::_ior : set_canonical(x->x()); return;
1.167 + }
1.168 + }
1.169 + break;
1.170 + case longTag:
1.171 + if (x->y()->type()->as_LongConstant()->value() == (jlong)0) {
1.172 + switch (x->op()) {
1.173 + case Bytecodes::_ladd: set_canonical(x->x()); return;
1.174 + case Bytecodes::_lsub: set_canonical(x->x()); return;
1.175 + case Bytecodes::_lmul: set_constant((jlong)0); return;
1.176 + // Note: for div and rem, make sure that C semantics
1.177 + // corresponds to Java semantics!
1.178 + case Bytecodes::_land: set_constant((jlong)0); return;
1.179 + case Bytecodes::_lor : set_canonical(x->x()); return;
1.180 + }
1.181 + }
1.182 + break;
1.183 + }
1.184 + }
1.185 +}
1.186 +
1.187 +
1.188 +void Canonicalizer::do_Phi (Phi* x) {}
1.189 +void Canonicalizer::do_Constant (Constant* x) {}
1.190 +void Canonicalizer::do_Local (Local* x) {}
1.191 +void Canonicalizer::do_LoadField (LoadField* x) {}
1.192 +
1.193 +// checks if v is in the block that is currently processed by
1.194 +// GraphBuilder. This is the only block that has not BlockEnd yet.
1.195 +static bool in_current_block(Value v) {
1.196 + int max_distance = 4;
1.197 + while (max_distance > 0 && v != NULL && v->as_BlockEnd() == NULL) {
1.198 + v = v->next();
1.199 + max_distance--;
1.200 + }
1.201 + return v == NULL;
1.202 +}
1.203 +
1.204 +void Canonicalizer::do_StoreField (StoreField* x) {
1.205 + // If a value is going to be stored into a field or array some of
1.206 + // the conversions emitted by javac are unneeded because the fields
1.207 + // are packed to their natural size.
1.208 + Convert* conv = x->value()->as_Convert();
1.209 + if (conv) {
1.210 + Value value = NULL;
1.211 + BasicType type = x->field()->type()->basic_type();
1.212 + switch (conv->op()) {
1.213 + case Bytecodes::_i2b: if (type == T_BYTE) value = conv->value(); break;
1.214 + case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) value = conv->value(); break;
1.215 + case Bytecodes::_i2c: if (type == T_CHAR || type == T_BYTE) value = conv->value(); break;
1.216 + }
1.217 + // limit this optimization to current block
1.218 + if (value != NULL && in_current_block(conv)) {
1.219 + set_canonical(new StoreField(x->obj(), x->offset(), x->field(), value, x->is_static(),
1.220 + x->state_before(), x->needs_patching()));
1.221 + return;
1.222 + }
1.223 + }
1.224 +
1.225 +}
1.226 +
1.227 +void Canonicalizer::do_ArrayLength (ArrayLength* x) {
1.228 + NewArray* array = x->array()->as_NewArray();
1.229 + if (array != NULL && array->length() != NULL) {
1.230 + Constant* length = array->length()->as_Constant();
1.231 + if (length != NULL) {
1.232 + // do not use the Constant itself, but create a new Constant
1.233 + // with same value Otherwise a Constant is live over multiple
1.234 + // blocks without being registered in a state array.
1.235 + assert(length->type()->as_IntConstant() != NULL, "array length must be integer");
1.236 + set_constant(length->type()->as_IntConstant()->value());
1.237 + }
1.238 + } else {
1.239 + LoadField* lf = x->array()->as_LoadField();
1.240 + if (lf != NULL) {
1.241 + ciField* field = lf->field();
1.242 + if (field->is_constant() && field->is_static()) {
1.243 + // final static field
1.244 + ciObject* c = field->constant_value().as_object();
1.245 + if (c->is_array()) {
1.246 + ciArray* array = (ciArray*) c;
1.247 + set_constant(array->length());
1.248 + }
1.249 + }
1.250 + }
1.251 + }
1.252 +}
1.253 +
1.254 +void Canonicalizer::do_LoadIndexed (LoadIndexed* x) {}
1.255 +void Canonicalizer::do_StoreIndexed (StoreIndexed* x) {
1.256 + // If a value is going to be stored into a field or array some of
1.257 + // the conversions emitted by javac are unneeded because the fields
1.258 + // are packed to their natural size.
1.259 + Convert* conv = x->value()->as_Convert();
1.260 + if (conv) {
1.261 + Value value = NULL;
1.262 + BasicType type = x->elt_type();
1.263 + switch (conv->op()) {
1.264 + case Bytecodes::_i2b: if (type == T_BYTE) value = conv->value(); break;
1.265 + case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) value = conv->value(); break;
1.266 + case Bytecodes::_i2c: if (type == T_CHAR || type == T_BYTE) value = conv->value(); break;
1.267 + }
1.268 + // limit this optimization to current block
1.269 + if (value != NULL && in_current_block(conv)) {
1.270 + set_canonical(new StoreIndexed(x->array(), x->index(), x->length(),
1.271 + x->elt_type(), value, x->state_before()));
1.272 + return;
1.273 + }
1.274 + }
1.275 +
1.276 +
1.277 +}
1.278 +
1.279 +
1.280 +void Canonicalizer::do_NegateOp(NegateOp* x) {
1.281 + ValueType* t = x->x()->type();
1.282 + if (t->is_constant()) {
1.283 + switch (t->tag()) {
1.284 + case intTag : set_constant(-t->as_IntConstant ()->value()); return;
1.285 + case longTag : set_constant(-t->as_LongConstant ()->value()); return;
1.286 + case floatTag : set_constant(-t->as_FloatConstant ()->value()); return;
1.287 + case doubleTag: set_constant(-t->as_DoubleConstant()->value()); return;
1.288 + default : ShouldNotReachHere();
1.289 + }
1.290 + }
1.291 +}
1.292 +
1.293 +
1.294 +void Canonicalizer::do_ArithmeticOp (ArithmeticOp* x) { do_Op2(x); }
1.295 +
1.296 +
1.297 +void Canonicalizer::do_ShiftOp (ShiftOp* x) {
1.298 + ValueType* t = x->x()->type();
1.299 + ValueType* t2 = x->y()->type();
1.300 + if (t->is_constant()) {
1.301 + switch (t->tag()) {
1.302 + case intTag : if (t->as_IntConstant()->value() == 0) { set_constant(0); return; } break;
1.303 + case longTag : if (t->as_LongConstant()->value() == (jlong)0) { set_constant(jlong_cast(0)); return; } break;
1.304 + default : ShouldNotReachHere();
1.305 + }
1.306 + if (t2->is_constant()) {
1.307 + if (t->tag() == intTag) {
1.308 + int value = t->as_IntConstant()->value();
1.309 + int shift = t2->as_IntConstant()->value() & 31;
1.310 + jint mask = ~(~0 << (32 - shift));
1.311 + if (shift == 0) mask = ~0;
1.312 + switch (x->op()) {
1.313 + case Bytecodes::_ishl: set_constant(value << shift); return;
1.314 + case Bytecodes::_ishr: set_constant(value >> shift); return;
1.315 + case Bytecodes::_iushr: set_constant((value >> shift) & mask); return;
1.316 + }
1.317 + } else if (t->tag() == longTag) {
1.318 + jlong value = t->as_LongConstant()->value();
1.319 + int shift = t2->as_IntConstant()->value() & 63;
1.320 + jlong mask = ~(~jlong_cast(0) << (64 - shift));
1.321 + if (shift == 0) mask = ~jlong_cast(0);
1.322 + switch (x->op()) {
1.323 + case Bytecodes::_lshl: set_constant(value << shift); return;
1.324 + case Bytecodes::_lshr: set_constant(value >> shift); return;
1.325 + case Bytecodes::_lushr: set_constant((value >> shift) & mask); return;
1.326 + }
1.327 + }
1.328 + }
1.329 + }
1.330 + if (t2->is_constant()) {
1.331 + switch (t2->tag()) {
1.332 + case intTag : if (t2->as_IntConstant()->value() == 0) set_canonical(x->x()); return;
1.333 + case longTag : if (t2->as_IntConstant()->value() == 0) set_canonical(x->x()); return;
1.334 + default : ShouldNotReachHere();
1.335 + }
1.336 + }
1.337 +}
1.338 +
1.339 +
1.340 +void Canonicalizer::do_LogicOp (LogicOp* x) { do_Op2(x); }
1.341 +void Canonicalizer::do_CompareOp (CompareOp* x) {
1.342 + if (x->x() == x->y()) {
1.343 + switch (x->x()->type()->tag()) {
1.344 + case longTag: set_constant(0); break;
1.345 + case floatTag: {
1.346 + FloatConstant* fc = x->x()->type()->as_FloatConstant();
1.347 + if (fc) {
1.348 + if (g_isnan(fc->value())) {
1.349 + set_constant(x->op() == Bytecodes::_fcmpl ? -1 : 1);
1.350 + } else {
1.351 + set_constant(0);
1.352 + }
1.353 + }
1.354 + break;
1.355 + }
1.356 + case doubleTag: {
1.357 + DoubleConstant* dc = x->x()->type()->as_DoubleConstant();
1.358 + if (dc) {
1.359 + if (g_isnan(dc->value())) {
1.360 + set_constant(x->op() == Bytecodes::_dcmpl ? -1 : 1);
1.361 + } else {
1.362 + set_constant(0);
1.363 + }
1.364 + }
1.365 + break;
1.366 + }
1.367 + }
1.368 + } else if (x->x()->type()->is_constant() && x->y()->type()->is_constant()) {
1.369 + switch (x->x()->type()->tag()) {
1.370 + case longTag: {
1.371 + jlong vx = x->x()->type()->as_LongConstant()->value();
1.372 + jlong vy = x->y()->type()->as_LongConstant()->value();
1.373 + if (vx == vy)
1.374 + set_constant(0);
1.375 + else if (vx < vy)
1.376 + set_constant(-1);
1.377 + else
1.378 + set_constant(1);
1.379 + break;
1.380 + }
1.381 +
1.382 + case floatTag: {
1.383 + float vx = x->x()->type()->as_FloatConstant()->value();
1.384 + float vy = x->y()->type()->as_FloatConstant()->value();
1.385 + if (g_isnan(vx) || g_isnan(vy))
1.386 + set_constant(x->op() == Bytecodes::_fcmpl ? -1 : 1);
1.387 + else if (vx == vy)
1.388 + set_constant(0);
1.389 + else if (vx < vy)
1.390 + set_constant(-1);
1.391 + else
1.392 + set_constant(1);
1.393 + break;
1.394 + }
1.395 +
1.396 + case doubleTag: {
1.397 + double vx = x->x()->type()->as_DoubleConstant()->value();
1.398 + double vy = x->y()->type()->as_DoubleConstant()->value();
1.399 + if (g_isnan(vx) || g_isnan(vy))
1.400 + set_constant(x->op() == Bytecodes::_dcmpl ? -1 : 1);
1.401 + else if (vx == vy)
1.402 + set_constant(0);
1.403 + else if (vx < vy)
1.404 + set_constant(-1);
1.405 + else
1.406 + set_constant(1);
1.407 + break;
1.408 + }
1.409 + }
1.410 +
1.411 + }
1.412 +}
1.413 +
1.414 +
1.415 +void Canonicalizer::do_IfInstanceOf(IfInstanceOf* x) {}
1.416 +
1.417 +void Canonicalizer::do_IfOp(IfOp* x) {
1.418 + // Caution: do not use do_Op2(x) here for now since
1.419 + // we map the condition to the op for now!
1.420 + move_const_to_right(x);
1.421 +}
1.422 +
1.423 +
1.424 +void Canonicalizer::do_Intrinsic (Intrinsic* x) {
1.425 + switch (x->id()) {
1.426 + case vmIntrinsics::_floatToRawIntBits : {
1.427 + FloatConstant* c = x->argument_at(0)->type()->as_FloatConstant();
1.428 + if (c != NULL) {
1.429 + JavaValue v;
1.430 + v.set_jfloat(c->value());
1.431 + set_constant(v.get_jint());
1.432 + }
1.433 + break;
1.434 + }
1.435 + case vmIntrinsics::_intBitsToFloat : {
1.436 + IntConstant* c = x->argument_at(0)->type()->as_IntConstant();
1.437 + if (c != NULL) {
1.438 + JavaValue v;
1.439 + v.set_jint(c->value());
1.440 + set_constant(v.get_jfloat());
1.441 + }
1.442 + break;
1.443 + }
1.444 + case vmIntrinsics::_doubleToRawLongBits : {
1.445 + DoubleConstant* c = x->argument_at(0)->type()->as_DoubleConstant();
1.446 + if (c != NULL) {
1.447 + JavaValue v;
1.448 + v.set_jdouble(c->value());
1.449 + set_constant(v.get_jlong());
1.450 + }
1.451 + break;
1.452 + }
1.453 + case vmIntrinsics::_longBitsToDouble : {
1.454 + LongConstant* c = x->argument_at(0)->type()->as_LongConstant();
1.455 + if (c != NULL) {
1.456 + JavaValue v;
1.457 + v.set_jlong(c->value());
1.458 + set_constant(v.get_jdouble());
1.459 + }
1.460 + break;
1.461 + }
1.462 + case vmIntrinsics::_isInstance : {
1.463 + assert(x->number_of_arguments() == 2, "wrong type");
1.464 +
1.465 + InstanceConstant* c = x->argument_at(0)->type()->as_InstanceConstant();
1.466 + if (c != NULL && !c->value()->is_null_object()) {
1.467 + // ciInstance::java_mirror_type() returns non-NULL only for Java mirrors
1.468 + ciType* t = c->value()->as_instance()->java_mirror_type();
1.469 + if (t->is_klass()) {
1.470 + // substitute cls.isInstance(obj) of a constant Class into
1.471 + // an InstantOf instruction
1.472 + InstanceOf* i = new InstanceOf(t->as_klass(), x->argument_at(1), x->state_before());
1.473 + set_canonical(i);
1.474 + // and try to canonicalize even further
1.475 + do_InstanceOf(i);
1.476 + } else {
1.477 + assert(t->is_primitive_type(), "should be a primitive type");
1.478 + // cls.isInstance(obj) always returns false for primitive classes
1.479 + set_constant(0);
1.480 + }
1.481 + }
1.482 + break;
1.483 + }
1.484 + }
1.485 +}
1.486 +
1.487 +void Canonicalizer::do_Convert (Convert* x) {
1.488 + if (x->value()->type()->is_constant()) {
1.489 + switch (x->op()) {
1.490 + case Bytecodes::_i2b: set_constant((int)((x->value()->type()->as_IntConstant()->value() << 24) >> 24)); break;
1.491 + case Bytecodes::_i2s: set_constant((int)((x->value()->type()->as_IntConstant()->value() << 16) >> 16)); break;
1.492 + case Bytecodes::_i2c: set_constant((int)(x->value()->type()->as_IntConstant()->value() & ((1<<16)-1))); break;
1.493 + case Bytecodes::_i2l: set_constant((jlong)(x->value()->type()->as_IntConstant()->value())); break;
1.494 + case Bytecodes::_i2f: set_constant((float)(x->value()->type()->as_IntConstant()->value())); break;
1.495 + case Bytecodes::_i2d: set_constant((double)(x->value()->type()->as_IntConstant()->value())); break;
1.496 + case Bytecodes::_l2i: set_constant((int)(x->value()->type()->as_LongConstant()->value())); break;
1.497 + case Bytecodes::_l2f: set_constant(SharedRuntime::l2f(x->value()->type()->as_LongConstant()->value())); break;
1.498 + case Bytecodes::_l2d: set_constant(SharedRuntime::l2d(x->value()->type()->as_LongConstant()->value())); break;
1.499 + case Bytecodes::_f2d: set_constant((double)(x->value()->type()->as_FloatConstant()->value())); break;
1.500 + case Bytecodes::_f2i: set_constant(SharedRuntime::f2i(x->value()->type()->as_FloatConstant()->value())); break;
1.501 + case Bytecodes::_f2l: set_constant(SharedRuntime::f2l(x->value()->type()->as_FloatConstant()->value())); break;
1.502 + case Bytecodes::_d2f: set_constant((float)(x->value()->type()->as_DoubleConstant()->value())); break;
1.503 + case Bytecodes::_d2i: set_constant(SharedRuntime::d2i(x->value()->type()->as_DoubleConstant()->value())); break;
1.504 + case Bytecodes::_d2l: set_constant(SharedRuntime::d2l(x->value()->type()->as_DoubleConstant()->value())); break;
1.505 + default:
1.506 + ShouldNotReachHere();
1.507 + }
1.508 + }
1.509 +
1.510 + Value value = x->value();
1.511 + BasicType type = T_ILLEGAL;
1.512 + LoadField* lf = value->as_LoadField();
1.513 + if (lf) {
1.514 + type = lf->field_type();
1.515 + } else {
1.516 + LoadIndexed* li = value->as_LoadIndexed();
1.517 + if (li) {
1.518 + type = li->elt_type();
1.519 + } else {
1.520 + Convert* conv = value->as_Convert();
1.521 + if (conv) {
1.522 + switch (conv->op()) {
1.523 + case Bytecodes::_i2b: type = T_BYTE; break;
1.524 + case Bytecodes::_i2s: type = T_SHORT; break;
1.525 + case Bytecodes::_i2c: type = T_CHAR; break;
1.526 + }
1.527 + }
1.528 + }
1.529 + }
1.530 + if (type != T_ILLEGAL) {
1.531 + switch (x->op()) {
1.532 + case Bytecodes::_i2b: if (type == T_BYTE) set_canonical(x->value()); break;
1.533 + case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) set_canonical(x->value()); break;
1.534 + case Bytecodes::_i2c: if (type == T_CHAR) set_canonical(x->value()); break;
1.535 + }
1.536 + } else {
1.537 + Op2* op2 = x->value()->as_Op2();
1.538 + if (op2 && op2->op() == Bytecodes::_iand && op2->y()->type()->is_constant()) {
1.539 + jint safebits = 0;
1.540 + jint mask = op2->y()->type()->as_IntConstant()->value();
1.541 + switch (x->op()) {
1.542 + case Bytecodes::_i2b: safebits = 0x7f; break;
1.543 + case Bytecodes::_i2s: safebits = 0x7fff; break;
1.544 + case Bytecodes::_i2c: safebits = 0xffff; break;
1.545 + }
1.546 + // When casting a masked integer to a smaller signed type, if
1.547 + // the mask doesn't include the sign bit the cast isn't needed.
1.548 + if (safebits && (mask & ~safebits) == 0) {
1.549 + set_canonical(x->value());
1.550 + }
1.551 + }
1.552 + }
1.553 +
1.554 +}
1.555 +
1.556 +void Canonicalizer::do_NullCheck (NullCheck* x) {
1.557 + if (x->obj()->as_NewArray() != NULL || x->obj()->as_NewInstance() != NULL) {
1.558 + set_canonical(x->obj());
1.559 + } else {
1.560 + Constant* con = x->obj()->as_Constant();
1.561 + if (con) {
1.562 + ObjectType* c = con->type()->as_ObjectType();
1.563 + if (c && c->is_loaded()) {
1.564 + ObjectConstant* oc = c->as_ObjectConstant();
1.565 + if (!oc || !oc->value()->is_null_object()) {
1.566 + set_canonical(con);
1.567 + }
1.568 + }
1.569 + }
1.570 + }
1.571 +}
1.572 +
1.573 +void Canonicalizer::do_TypeCast (TypeCast* x) {}
1.574 +void Canonicalizer::do_Invoke (Invoke* x) {}
1.575 +void Canonicalizer::do_NewInstance (NewInstance* x) {}
1.576 +void Canonicalizer::do_NewTypeArray (NewTypeArray* x) {}
1.577 +void Canonicalizer::do_NewObjectArray (NewObjectArray* x) {}
1.578 +void Canonicalizer::do_NewMultiArray (NewMultiArray* x) {}
1.579 +void Canonicalizer::do_CheckCast (CheckCast* x) {
1.580 + if (x->klass()->is_loaded()) {
1.581 + Value obj = x->obj();
1.582 + ciType* klass = obj->exact_type();
1.583 + if (klass == NULL) klass = obj->declared_type();
1.584 + if (klass != NULL && klass->is_loaded() && klass->is_subtype_of(x->klass())) {
1.585 + set_canonical(obj);
1.586 + return;
1.587 + }
1.588 + // checkcast of null returns null
1.589 + if (obj->as_Constant() && obj->type()->as_ObjectType()->constant_value()->is_null_object()) {
1.590 + set_canonical(obj);
1.591 + }
1.592 + }
1.593 +}
1.594 +void Canonicalizer::do_InstanceOf (InstanceOf* x) {
1.595 + if (x->klass()->is_loaded()) {
1.596 + Value obj = x->obj();
1.597 + ciType* exact = obj->exact_type();
1.598 + if (exact != NULL && exact->is_loaded() && (obj->as_NewInstance() || obj->as_NewArray())) {
1.599 + set_constant(exact->is_subtype_of(x->klass()) ? 1 : 0);
1.600 + return;
1.601 + }
1.602 + // instanceof null returns false
1.603 + if (obj->as_Constant() && obj->type()->as_ObjectType()->constant_value()->is_null_object()) {
1.604 + set_constant(0);
1.605 + }
1.606 + }
1.607 +
1.608 +}
1.609 +void Canonicalizer::do_MonitorEnter (MonitorEnter* x) {}
1.610 +void Canonicalizer::do_MonitorExit (MonitorExit* x) {}
1.611 +void Canonicalizer::do_BlockBegin (BlockBegin* x) {}
1.612 +void Canonicalizer::do_Goto (Goto* x) {}
1.613 +
1.614 +
1.615 +static bool is_true(jlong x, If::Condition cond, jlong y) {
1.616 + switch (cond) {
1.617 + case If::eql: return x == y;
1.618 + case If::neq: return x != y;
1.619 + case If::lss: return x < y;
1.620 + case If::leq: return x <= y;
1.621 + case If::gtr: return x > y;
1.622 + case If::geq: return x >= y;
1.623 + }
1.624 + ShouldNotReachHere();
1.625 + return false;
1.626 +}
1.627 +
1.628 +static bool is_safepoint(BlockEnd* x, BlockBegin* sux) {
1.629 + // An Instruction with multiple successors, x, is replaced by a Goto
1.630 + // to a single successor, sux. Is a safepoint check needed = was the
1.631 + // instruction being replaced a safepoint and the single remaining
1.632 + // successor a back branch?
1.633 + return x->is_safepoint() && (sux->bci() < x->state_before()->bci());
1.634 +}
1.635 +
1.636 +void Canonicalizer::do_If(If* x) {
1.637 + // move const to right
1.638 + if (x->x()->type()->is_constant()) x->swap_operands();
1.639 + // simplify
1.640 + const Value l = x->x(); ValueType* lt = l->type();
1.641 + const Value r = x->y(); ValueType* rt = r->type();
1.642 +
1.643 + if (l == r && !lt->is_float_kind()) {
1.644 + // pattern: If (a cond a) => simplify to Goto
1.645 + BlockBegin* sux;
1.646 + switch (x->cond()) {
1.647 + case If::eql: sux = x->sux_for(true); break;
1.648 + case If::neq: sux = x->sux_for(false); break;
1.649 + case If::lss: sux = x->sux_for(false); break;
1.650 + case If::leq: sux = x->sux_for(true); break;
1.651 + case If::gtr: sux = x->sux_for(false); break;
1.652 + case If::geq: sux = x->sux_for(true); break;
1.653 + }
1.654 + // If is a safepoint then the debug information should come from the state_before of the If.
1.655 + set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux)));
1.656 + return;
1.657 + }
1.658 +
1.659 + if (lt->is_constant() && rt->is_constant()) {
1.660 + if (x->x()->as_Constant() != NULL) {
1.661 + // pattern: If (lc cond rc) => simplify to: Goto
1.662 + BlockBegin* sux = x->x()->as_Constant()->compare(x->cond(), x->y(),
1.663 + x->sux_for(true),
1.664 + x->sux_for(false));
1.665 + if (sux != NULL) {
1.666 + // If is a safepoint then the debug information should come from the state_before of the If.
1.667 + set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux)));
1.668 + }
1.669 + }
1.670 + } else if (rt->as_IntConstant() != NULL) {
1.671 + // pattern: If (l cond rc) => investigate further
1.672 + const jint rc = rt->as_IntConstant()->value();
1.673 + if (l->as_CompareOp() != NULL) {
1.674 + // pattern: If ((a cmp b) cond rc) => simplify to: If (x cond y) or: Goto
1.675 + CompareOp* cmp = l->as_CompareOp();
1.676 + bool unordered_is_less = cmp->op() == Bytecodes::_fcmpl || cmp->op() == Bytecodes::_dcmpl;
1.677 + BlockBegin* lss_sux = x->sux_for(is_true(-1, x->cond(), rc)); // successor for a < b
1.678 + BlockBegin* eql_sux = x->sux_for(is_true( 0, x->cond(), rc)); // successor for a = b
1.679 + BlockBegin* gtr_sux = x->sux_for(is_true(+1, x->cond(), rc)); // successor for a > b
1.680 + BlockBegin* nan_sux = unordered_is_less ? lss_sux : gtr_sux ; // successor for unordered
1.681 + // Note: At this point all successors (lss_sux, eql_sux, gtr_sux, nan_sux) are
1.682 + // equal to x->tsux() or x->fsux(). Furthermore, nan_sux equals either
1.683 + // lss_sux or gtr_sux.
1.684 + if (lss_sux == eql_sux && eql_sux == gtr_sux) {
1.685 + // all successors identical => simplify to: Goto
1.686 + set_canonical(new Goto(lss_sux, x->state_before(), x->is_safepoint()));
1.687 + } else {
1.688 + // two successors differ and two successors are the same => simplify to: If (x cmp y)
1.689 + // determine new condition & successors
1.690 + If::Condition cond;
1.691 + BlockBegin* tsux = NULL;
1.692 + BlockBegin* fsux = NULL;
1.693 + if (lss_sux == eql_sux) { cond = If::leq; tsux = lss_sux; fsux = gtr_sux; }
1.694 + else if (lss_sux == gtr_sux) { cond = If::neq; tsux = lss_sux; fsux = eql_sux; }
1.695 + else if (eql_sux == gtr_sux) { cond = If::geq; tsux = eql_sux; fsux = lss_sux; }
1.696 + else { ShouldNotReachHere(); }
1.697 + If* canon = new If(cmp->x(), cond, nan_sux == tsux, cmp->y(), tsux, fsux, cmp->state_before(), x->is_safepoint());
1.698 + if (cmp->x() == cmp->y()) {
1.699 + do_If(canon);
1.700 + } else {
1.701 + if (compilation()->profile_branches()) {
1.702 + // TODO: If profiling, leave floating point comparisons unoptimized.
1.703 + // We currently do not support profiling of the unordered case.
1.704 + switch(cmp->op()) {
1.705 + case Bytecodes::_fcmpl: case Bytecodes::_fcmpg:
1.706 + case Bytecodes::_dcmpl: case Bytecodes::_dcmpg:
1.707 + set_canonical(x);
1.708 + return;
1.709 + }
1.710 + }
1.711 + set_bci(cmp->state_before()->bci());
1.712 + set_canonical(canon);
1.713 + }
1.714 + }
1.715 + } else if (l->as_InstanceOf() != NULL) {
1.716 + // NOTE: Code permanently disabled for now since it leaves the old InstanceOf
1.717 + // instruction in the graph (it is pinned). Need to fix this at some point.
1.718 + // It should also be left in the graph when generating a profiled method version or Goto
1.719 + // has to know that it was an InstanceOf.
1.720 + return;
1.721 + // pattern: If ((obj instanceof klass) cond rc) => simplify to: IfInstanceOf or: Goto
1.722 + InstanceOf* inst = l->as_InstanceOf();
1.723 + BlockBegin* is_inst_sux = x->sux_for(is_true(1, x->cond(), rc)); // successor for instanceof == 1
1.724 + BlockBegin* no_inst_sux = x->sux_for(is_true(0, x->cond(), rc)); // successor for instanceof == 0
1.725 + if (is_inst_sux == no_inst_sux && inst->is_loaded()) {
1.726 + // both successors identical and klass is loaded => simplify to: Goto
1.727 + set_canonical(new Goto(is_inst_sux, x->state_before(), x->is_safepoint()));
1.728 + } else {
1.729 + // successors differ => simplify to: IfInstanceOf
1.730 + set_canonical(new IfInstanceOf(inst->klass(), inst->obj(), true, inst->state_before()->bci(), is_inst_sux, no_inst_sux));
1.731 + }
1.732 + }
1.733 + } else if (rt == objectNull && (l->as_NewInstance() || l->as_NewArray())) {
1.734 + if (x->cond() == Instruction::eql) {
1.735 + BlockBegin* sux = x->fsux();
1.736 + set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux)));
1.737 + } else {
1.738 + assert(x->cond() == Instruction::neq, "only other valid case");
1.739 + BlockBegin* sux = x->tsux();
1.740 + set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux)));
1.741 + }
1.742 + }
1.743 +}
1.744 +
1.745 +
1.746 +void Canonicalizer::do_TableSwitch(TableSwitch* x) {
1.747 + if (x->tag()->type()->is_constant()) {
1.748 + int v = x->tag()->type()->as_IntConstant()->value();
1.749 + BlockBegin* sux = x->default_sux();
1.750 + if (v >= x->lo_key() && v <= x->hi_key()) {
1.751 + sux = x->sux_at(v - x->lo_key());
1.752 + }
1.753 + set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux)));
1.754 + } else if (x->number_of_sux() == 1) {
1.755 + // NOTE: Code permanently disabled for now since the switch statement's
1.756 + // tag expression may produce side-effects in which case it must
1.757 + // be executed.
1.758 + return;
1.759 + // simplify to Goto
1.760 + set_canonical(new Goto(x->default_sux(), x->state_before(), x->is_safepoint()));
1.761 + } else if (x->number_of_sux() == 2) {
1.762 + // NOTE: Code permanently disabled for now since it produces two new nodes
1.763 + // (Constant & If) and the Canonicalizer cannot return them correctly
1.764 + // yet. For now we copied the corresponding code directly into the
1.765 + // GraphBuilder (i.e., we should never reach here).
1.766 + return;
1.767 + // simplify to If
1.768 + assert(x->lo_key() == x->hi_key(), "keys must be the same");
1.769 + Constant* key = new Constant(new IntConstant(x->lo_key()));
1.770 + set_canonical(new If(x->tag(), If::eql, true, key, x->sux_at(0), x->default_sux(), x->state_before(), x->is_safepoint()));
1.771 + }
1.772 +}
1.773 +
1.774 +
1.775 +void Canonicalizer::do_LookupSwitch(LookupSwitch* x) {
1.776 + if (x->tag()->type()->is_constant()) {
1.777 + int v = x->tag()->type()->as_IntConstant()->value();
1.778 + BlockBegin* sux = x->default_sux();
1.779 + for (int i = 0; i < x->length(); i++) {
1.780 + if (v == x->key_at(i)) {
1.781 + sux = x->sux_at(i);
1.782 + }
1.783 + }
1.784 + set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux)));
1.785 + } else if (x->number_of_sux() == 1) {
1.786 + // NOTE: Code permanently disabled for now since the switch statement's
1.787 + // tag expression may produce side-effects in which case it must
1.788 + // be executed.
1.789 + return;
1.790 + // simplify to Goto
1.791 + set_canonical(new Goto(x->default_sux(), x->state_before(), x->is_safepoint()));
1.792 + } else if (x->number_of_sux() == 2) {
1.793 + // NOTE: Code permanently disabled for now since it produces two new nodes
1.794 + // (Constant & If) and the Canonicalizer cannot return them correctly
1.795 + // yet. For now we copied the corresponding code directly into the
1.796 + // GraphBuilder (i.e., we should never reach here).
1.797 + return;
1.798 + // simplify to If
1.799 + assert(x->length() == 1, "length must be the same");
1.800 + Constant* key = new Constant(new IntConstant(x->key_at(0)));
1.801 + set_canonical(new If(x->tag(), If::eql, true, key, x->sux_at(0), x->default_sux(), x->state_before(), x->is_safepoint()));
1.802 + }
1.803 +}
1.804 +
1.805 +
1.806 +void Canonicalizer::do_Return (Return* x) {}
1.807 +void Canonicalizer::do_Throw (Throw* x) {}
1.808 +void Canonicalizer::do_Base (Base* x) {}
1.809 +void Canonicalizer::do_OsrEntry (OsrEntry* x) {}
1.810 +void Canonicalizer::do_ExceptionObject(ExceptionObject* x) {}
1.811 +
1.812 +static bool match_index_and_scale(Instruction* instr,
1.813 + Instruction** index,
1.814 + int* log2_scale,
1.815 + Instruction** instr_to_unpin) {
1.816 + *instr_to_unpin = NULL;
1.817 +
1.818 + // Skip conversion ops
1.819 + Convert* convert = instr->as_Convert();
1.820 + if (convert != NULL) {
1.821 + instr = convert->value();
1.822 + }
1.823 +
1.824 + ShiftOp* shift = instr->as_ShiftOp();
1.825 + if (shift != NULL) {
1.826 + if (shift->is_pinned()) {
1.827 + *instr_to_unpin = shift;
1.828 + }
1.829 + // Constant shift value?
1.830 + Constant* con = shift->y()->as_Constant();
1.831 + if (con == NULL) return false;
1.832 + // Well-known type and value?
1.833 + IntConstant* val = con->type()->as_IntConstant();
1.834 + if (val == NULL) return false;
1.835 + if (shift->x()->type() != intType) return false;
1.836 + *index = shift->x();
1.837 + int tmp_scale = val->value();
1.838 + if (tmp_scale >= 0 && tmp_scale < 4) {
1.839 + *log2_scale = tmp_scale;
1.840 + return true;
1.841 + } else {
1.842 + return false;
1.843 + }
1.844 + }
1.845 +
1.846 + ArithmeticOp* arith = instr->as_ArithmeticOp();
1.847 + if (arith != NULL) {
1.848 + if (arith->is_pinned()) {
1.849 + *instr_to_unpin = arith;
1.850 + }
1.851 + // Check for integer multiply
1.852 + if (arith->op() == Bytecodes::_imul) {
1.853 + // See if either arg is a known constant
1.854 + Constant* con = arith->x()->as_Constant();
1.855 + if (con != NULL) {
1.856 + *index = arith->y();
1.857 + } else {
1.858 + con = arith->y()->as_Constant();
1.859 + if (con == NULL) return false;
1.860 + *index = arith->x();
1.861 + }
1.862 + if ((*index)->type() != intType) return false;
1.863 + // Well-known type and value?
1.864 + IntConstant* val = con->type()->as_IntConstant();
1.865 + if (val == NULL) return false;
1.866 + switch (val->value()) {
1.867 + case 1: *log2_scale = 0; return true;
1.868 + case 2: *log2_scale = 1; return true;
1.869 + case 4: *log2_scale = 2; return true;
1.870 + case 8: *log2_scale = 3; return true;
1.871 + default: return false;
1.872 + }
1.873 + }
1.874 + }
1.875 +
1.876 + // Unknown instruction sequence; don't touch it
1.877 + return false;
1.878 +}
1.879 +
1.880 +
1.881 +static bool match(UnsafeRawOp* x,
1.882 + Instruction** base,
1.883 + Instruction** index,
1.884 + int* log2_scale) {
1.885 + Instruction* instr_to_unpin = NULL;
1.886 + ArithmeticOp* root = x->base()->as_ArithmeticOp();
1.887 + if (root == NULL) return false;
1.888 + // Limit ourselves to addition for now
1.889 + if (root->op() != Bytecodes::_ladd) return false;
1.890 + // Try to find shift or scale op
1.891 + if (match_index_and_scale(root->y(), index, log2_scale, &instr_to_unpin)) {
1.892 + *base = root->x();
1.893 + } else if (match_index_and_scale(root->x(), index, log2_scale, &instr_to_unpin)) {
1.894 + *base = root->y();
1.895 + } else if (root->y()->as_Convert() != NULL) {
1.896 + Convert* convert = root->y()->as_Convert();
1.897 + if (convert->op() == Bytecodes::_i2l && convert->value()->type() == intType) {
1.898 + // pick base and index, setting scale at 1
1.899 + *base = root->x();
1.900 + *index = convert->value();
1.901 + *log2_scale = 0;
1.902 + } else {
1.903 + return false;
1.904 + }
1.905 + } else {
1.906 + // doesn't match any expected sequences
1.907 + return false;
1.908 + }
1.909 +
1.910 + // If the value is pinned then it will be always be computed so
1.911 + // there's no profit to reshaping the expression.
1.912 + return !root->is_pinned();
1.913 +}
1.914 +
1.915 +
1.916 +void Canonicalizer::do_UnsafeRawOp(UnsafeRawOp* x) {
1.917 + Instruction* base = NULL;
1.918 + Instruction* index = NULL;
1.919 + int log2_scale;
1.920 +
1.921 + if (match(x, &base, &index, &log2_scale)) {
1.922 + x->set_base(base);
1.923 + x->set_index(index);
1.924 + x->set_log2_scale(log2_scale);
1.925 + if (PrintUnsafeOptimization) {
1.926 + tty->print_cr("Canonicalizer: UnsafeRawOp id %d: base = id %d, index = id %d, log2_scale = %d",
1.927 + x->id(), x->base()->id(), x->index()->id(), x->log2_scale());
1.928 + }
1.929 + }
1.930 +}
1.931 +
1.932 +void Canonicalizer::do_RoundFP(RoundFP* x) {}
1.933 +void Canonicalizer::do_UnsafeGetRaw(UnsafeGetRaw* x) { if (OptimizeUnsafes) do_UnsafeRawOp(x); }
1.934 +void Canonicalizer::do_UnsafePutRaw(UnsafePutRaw* x) { if (OptimizeUnsafes) do_UnsafeRawOp(x); }
1.935 +void Canonicalizer::do_UnsafeGetObject(UnsafeGetObject* x) {}
1.936 +void Canonicalizer::do_UnsafePutObject(UnsafePutObject* x) {}
1.937 +void Canonicalizer::do_UnsafeGetAndSetObject(UnsafeGetAndSetObject* x) {}
1.938 +void Canonicalizer::do_UnsafePrefetchRead (UnsafePrefetchRead* x) {}
1.939 +void Canonicalizer::do_UnsafePrefetchWrite(UnsafePrefetchWrite* x) {}
1.940 +void Canonicalizer::do_ProfileCall(ProfileCall* x) {}
1.941 +void Canonicalizer::do_ProfileReturnType(ProfileReturnType* x) {}
1.942 +void Canonicalizer::do_ProfileInvoke(ProfileInvoke* x) {}
1.943 +void Canonicalizer::do_RuntimeCall(RuntimeCall* x) {}
1.944 +void Canonicalizer::do_RangeCheckPredicate(RangeCheckPredicate* x) {}
1.945 +#ifdef ASSERT
1.946 +void Canonicalizer::do_Assert(Assert* x) {}
1.947 +#endif
1.948 +void Canonicalizer::do_MemBar(MemBar* x) {}
