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6705887: Compressed Oops: generate x64 addressing and implicit null checks with narrow oops

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Generate addresses and implicit null checks with narrow oops to avoid decoding.

Reviewed-by: jrose, never
This commit is contained in:
Vladimir Kozlov 2008-05-29 12:04:14 -07:00
parent 646ceb4a45
commit a1f50998ae
20 changed files with 138 additions and 81 deletions
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49
hotspot/src/share/vm/opto/compile.cpp
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@ -1842,6 +1842,7 @@ static bool oop_offset_is_sane(const TypeInstPtr* tp) {
// Implement items 1-5 from final_graph_reshaping below.
static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
if ( n->outcnt() == 0 ) return; // dead node
uint nop = n->Opcode();
// Check for 2-input instruction with "last use" on right input.
@ -1908,7 +1909,7 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
break;
case Op_Opaque1: // Remove Opaque Nodes before matching
case Op_Opaque2: // Remove Opaque Nodes before matching
n->replace_by(n->in(1));
n->subsume_by(n->in(1));
break;
case Op_CallStaticJava:
case Op_CallJava:
@ -2001,24 +2002,34 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
#ifdef _LP64
case Op_CmpP:
if( n->in(1)->Opcode() == Op_DecodeN ) {
// Do this transformation here to preserve CmpPNode::sub() and
// other TypePtr related Ideal optimizations (for example, ptr nullness).
if( n->in(1)->is_DecodeN() ) {
Compile* C = Compile::current();
Node* in2 = NULL;
if( n->in(2)->Opcode() == Op_DecodeN ) {
if( n->in(2)->is_DecodeN() ) {
in2 = n->in(2)->in(1);
} else if ( n->in(2)->Opcode() == Op_ConP ) {
const Type* t = n->in(2)->bottom_type();
if (t == TypePtr::NULL_PTR) {
Node *in1 = n->in(1);
uint i = 0;
for (; i < in1->outcnt(); i++) {
if (in1->raw_out(i)->is_AddP())
break;
}
if (i >= in1->outcnt()) {
// Don't replace CmpP(o ,null) if 'o' is used in AddP
// to generate implicit NULL check.
if (Matcher::clone_shift_expressions) {
// x86, ARM and friends can handle 2 adds in addressing mode.
// Decode a narrow oop and do implicit NULL check in address
// [R12 + narrow_oop_reg<<3 + offset]
in2 = ConNode::make(C, TypeNarrowOop::NULL_PTR);
} else {
// Don't replace CmpP(o ,null) if 'o' is used in AddP
// to generate implicit NULL check on Sparc where
// narrow oops can't be used in address.
uint i = 0;
for (; i < in1->outcnt(); i++) {
if (in1->raw_out(i)->is_AddP())
break;
}
if (i >= in1->outcnt()) {
in2 = ConNode::make(C, TypeNarrowOop::NULL_PTR);
}
}
} else if (t->isa_oopptr()) {
in2 = ConNode::make(C, t->is_oopptr()->make_narrowoop());
@ -2026,7 +2037,7 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
}
if( in2 != NULL ) {
Node* cmpN = new (C, 3) CmpNNode(n->in(1)->in(1), in2);
n->replace_by( cmpN );
n->subsume_by( cmpN );
}
}
#endif
@ -2040,13 +2051,13 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
Compile* C = Compile::current();
if (Matcher::has_match_rule(Op_DivModI)) {
DivModINode* divmod = DivModINode::make(C, n);
d->replace_by(divmod->div_proj());
n->replace_by(divmod->mod_proj());
d->subsume_by(divmod->div_proj());
n->subsume_by(divmod->mod_proj());
} else {
// replace a%b with a-((a/b)*b)
Node* mult = new (C, 3) MulINode(d, d->in(2));
Node* sub = new (C, 3) SubINode(d->in(1), mult);
n->replace_by( sub );
n->subsume_by( sub );
}
}
}
@ -2061,13 +2072,13 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
Compile* C = Compile::current();
if (Matcher::has_match_rule(Op_DivModL)) {
DivModLNode* divmod = DivModLNode::make(C, n);
d->replace_by(divmod->div_proj());
n->replace_by(divmod->mod_proj());
d->subsume_by(divmod->div_proj());
n->subsume_by(divmod->mod_proj());
} else {
// replace a%b with a-((a/b)*b)
Node* mult = new (C, 3) MulLNode(d, d->in(2));
Node* sub = new (C, 3) SubLNode(d->in(1), mult);
n->replace_by( sub );
n->subsume_by( sub );
}
}
}
@ -2113,7 +2124,7 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &fpu ) {
// Replace many operand PackNodes with a binary tree for matching
PackNode* p = (PackNode*) n;
Node* btp = p->binaryTreePack(Compile::current(), 1, n->req());
n->replace_by(btp);
n->subsume_by(btp);
}
break;
default: