8216050: Superword optimization fails with assert(0 <= i && i < _len) failed: illegal index
Summary: Fix for the crash by matching the operands by swapping to right positions.
Reviewed-by: thartmann, kvn
--- a/src/hotspot/cpu/x86/x86.ad Tue Jan 15 10:55:26 2019 -0800
+++ b/src/hotspot/cpu/x86/x86.ad Tue Jan 15 11:19:14 2019 -0800
@@ -9936,6 +9936,7 @@
__ evpdpwssd($dst$$XMMRegister, $src1$$XMMRegister, $src2$$XMMRegister, vector_len);
%}
ins_pipe( pipe_slow );
+ ins_cost(10);
%}
instruct vmuladdadd8S4I_reg(vecX dst, vecX src1, vecX src2) %{
@@ -9947,6 +9948,7 @@
__ evpdpwssd($dst$$XMMRegister, $src1$$XMMRegister, $src2$$XMMRegister, vector_len);
%}
ins_pipe( pipe_slow );
+ ins_cost(10);
%}
instruct vmuladdadd16S8I_reg(vecY dst, vecY src1, vecY src2) %{
@@ -9958,6 +9960,7 @@
__ evpdpwssd($dst$$XMMRegister, $src1$$XMMRegister, $src2$$XMMRegister, vector_len);
%}
ins_pipe( pipe_slow );
+ ins_cost(10);
%}
instruct vmuladdadd32S16I_reg(vecZ dst, vecZ src1, vecZ src2) %{
@@ -9969,6 +9972,7 @@
__ evpdpwssd($dst$$XMMRegister, $src1$$XMMRegister, $src2$$XMMRegister, vector_len);
%}
ins_pipe( pipe_slow );
+ ins_cost(10);
%}
// --------------------------------- PopCount --------------------------------------
--- a/src/hotspot/share/opto/loopopts.cpp Tue Jan 15 10:55:26 2019 -0800
+++ b/src/hotspot/share/opto/loopopts.cpp Tue Jan 15 11:19:14 2019 -0800
@@ -532,6 +532,12 @@
register_new_node(nn, get_ctrl(n));
_igvn.replace_node(n, nn);
return nn;
+ } else if ((adr1->in(AddPNode::Base) == adr4->in(AddPNode::Base)) &&
+ (adr2->in(AddPNode::Base) == adr3->in(AddPNode::Base))) {
+ nn = new MulAddS2INode(mul_in1, mul_in2, mul_in4, mul_in3);
+ register_new_node(nn, get_ctrl(n));
+ _igvn.replace_node(n, nn);
+ return nn;
}
}
}
--- a/src/hotspot/share/opto/mulnode.cpp Tue Jan 15 10:55:26 2019 -0800
+++ b/src/hotspot/share/opto/mulnode.cpp Tue Jan 15 11:19:14 2019 -0800
@@ -1401,3 +1401,12 @@
return TypeF::make(fma(f1, f2, f3));
#endif
}
+
+//=============================================================================
+//------------------------------hash-------------------------------------------
+// Hash function for MulAddS2INode. Operation is commutative with commutative pairs.
+// The hash function must return the same value when edge swapping is performed.
+uint MulAddS2INode::hash() const {
+ return (uintptr_t)in(1) + (uintptr_t)in(2) + (uintptr_t)in(3) + (uintptr_t)in(4) + Opcode();
+}
+
--- a/src/hotspot/share/opto/mulnode.hpp Tue Jan 15 10:55:26 2019 -0800
+++ b/src/hotspot/share/opto/mulnode.hpp Tue Jan 15 11:19:14 2019 -0800
@@ -289,6 +289,7 @@
// Multiply shorts into integers and add them.
// Semantics: I_OUT = S1 * S2 + S3 * S4
class MulAddS2INode : public Node {
+ virtual uint hash() const;
public:
MulAddS2INode(Node* in1, Node *in2, Node *in3, Node* in4) : Node(0, in1, in2, in3, in4) {}
virtual int Opcode() const;
--- a/src/hotspot/share/opto/superword.cpp Tue Jan 15 10:55:26 2019 -0800
+++ b/src/hotspot/share/opto/superword.cpp Tue Jan 15 11:19:14 2019 -0800
@@ -1445,7 +1445,7 @@
Node* t1 = s1->fast_out(i);
// Only allow operand swap on commuting operations
- if (!t1->is_Add() && !t1->is_Mul()) {
+ if (!t1->is_Add() && !t1->is_Mul() && !VectorNode::is_muladds2i(t1)) {
break;
}
@@ -1500,9 +1500,23 @@
if ((i1 == (3-i2)) && (u2->is_Add() || u2->is_Mul())) {
// Further analysis relies on operands position matching.
u2->swap_edges(i1, i2);
+ } else if (VectorNode::is_muladds2i(u2) && u1 != u2) {
+ if (i1 == 5 - i2) { // ((i1 == 3 && i2 == 2) || (i1 == 2 && i2 == 3) || (i1 == 1 && i2 == 4) || (i1 == 4 && i2 == 1))
+ u2->swap_edges(1, 2);
+ u2->swap_edges(3, 4);
+ }
+ if (i1 == 3 - i2 || i1 == 7 - i2) { // ((i1 == 1 && i2 == 2) || (i1 == 2 && i2 == 1) || (i1 == 3 && i2 == 4) || (i1 == 4 && i2 == 3))
+ u2->swap_edges(2, 3);
+ u2->swap_edges(1, 4);
+ }
+ return false; // Just swap the edges, the muladds2i nodes get packed in follow_use_defs
} else {
return false;
}
+ } else if (i1 == i2 && VectorNode::is_muladds2i(u2) && u1 != u2) {
+ u2->swap_edges(1, 3);
+ u2->swap_edges(2, 4);
+ return false; // Just swap the edges, the muladds2i nodes get packed in follow_use_defs
}
} while (i1 < ct);
return true;