infernap12/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2026-02-13 20:05:31 +00:00
Code Issues Packages Projects Releases Wiki Activity

8244924: Additional fix for JDK-8241119

Browse Source 
Reviewed-by: kvn, vlivanov, rhalade, ahgross
This commit is contained in:
Tobias Hartmann 2020-05-13 09:07:02 +02:00 committed by Henry Jen
parent 62a03bd387
commit 7c05f32bc9
1 changed files with 26 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
src/hotspot/share/opto/addnode.cpp
View File

@ -1004,6 +1004,14 @@ const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
}
// Check if addition of an integer with type 't' and a constant 'c' can overflow
static bool can_overflow(const TypeInt* t, jint c) {
jint t_lo = t->_lo;
jint t_hi = t->_hi;
return ((c < 0 && (java_add(t_lo, c) > t_lo)) ||
(c > 0 && (java_add(t_hi, c) < t_hi)));
}
//=============================================================================
//------------------------------Idealize---------------------------------------
// MINs show up in range-check loop limit calculations. Look for
@ -1026,7 +1034,7 @@ Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
// Get left input & constant
Node *x = l;
int x_off = 0;
jint x_off = 0;
if( x->Opcode() == Op_AddI && // Check for "x+c0" and collect constant
x->in(2)->is_Con() ) {
const Type *t = x->in(2)->bottom_type();
@ -1037,7 +1045,7 @@ Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
// Scan a right-spline-tree for MINs
Node *y = r;
int y_off = 0;
jint y_off = 0;
// Check final part of MIN tree
if( y->Opcode() == Op_AddI && // Check for "y+c1" and collect constant
y->in(2)->is_Con() ) {
@ -1051,6 +1059,7 @@ Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
return this;
}
const TypeInt* tx = phase->type(x)->isa_int();
if( r->Opcode() == Op_MinI ) {
assert( r != r->in(2), "dead loop in MinINode::Ideal" );
@ -1067,18 +1076,23 @@ Node *MinINode::Ideal(PhaseGVN *phase, bool can_reshape) {
if( x->_idx > y->_idx )
return new MinINode(r->in(1),phase->transform(new MinINode(l,r->in(2))));
// See if covers: MIN2(x+c0,MIN2(y+c1,z))
if( !phase->eqv(x,y) ) return NULL;
// If (y == x) transform MIN2(x+c0, MIN2(x+c1,z)) into
// MIN2(x+c0 or x+c1 which less, z).
return new MinINode(phase->transform(new AddINode(x,phase->intcon(MIN2(x_off,y_off)))),r->in(2));
// Transform MIN2(x + c0, MIN2(x + c1, z)) into MIN2(x + MIN2(c0, c1), z)
// if x == y and the additions can't overflow.
if (phase->eqv(x,y) &&
!can_overflow(tx, x_off) &&
!can_overflow(tx, y_off)) {
return new MinINode(phase->transform(new AddINode(x, phase->intcon(MIN2(x_off, y_off)))), r->in(2));
}
} else {
// See if covers: MIN2(x+c0,y+c1)
if( !phase->eqv(x,y) ) return NULL;
// If (y == x) transform MIN2(x+c0,x+c1) into x+c0 or x+c1 which less.
return new AddINode(x,phase->intcon(MIN2(x_off,y_off)));
// Transform MIN2(x + c0, y + c1) into x + MIN2(c0, c1)
// if x == y and the additions can't overflow.
if (phase->eqv(x,y) &&
!can_overflow(tx, x_off) &&
!can_overflow(tx, y_off)) {
return new AddINode(x,phase->intcon(MIN2(x_off,y_off)));
}
}
return NULL;
}
//------------------------------add_ring---------------------------------------