From 9237cae0e384d34df0a84e232c130cabe85cbd77 Mon Sep 17 00:00:00 2001 From: Aleksey Shipilev Date: Tue, 19 Dec 2023 11:30:24 +0000 Subject: [PATCH] 8317507: C2 compilation fails with "Exceeded _node_regs array" Backport-of: a5818972c16bd883d768ff2fb23a8aa9e0142c65 --- src/hotspot/share/adlc/output_c.cpp | 3 + .../regalloc/TestNodeRegArrayOverflow.java | 599 ++++++++++++++++++ 2 files changed, 602 insertions(+) create mode 100644 test/hotspot/jtreg/compiler/regalloc/TestNodeRegArrayOverflow.java diff --git a/src/hotspot/share/adlc/output_c.cpp b/src/hotspot/share/adlc/output_c.cpp index 9d9154eaec1..9fe8b6e3afe 100644 --- a/src/hotspot/share/adlc/output_c.cpp +++ b/src/hotspot/share/adlc/output_c.cpp @@ -3040,6 +3040,9 @@ static void define_fill_new_machnode(bool used, FILE *fp_cpp) { fprintf(fp_cpp, " if( i != cisc_operand() ) \n"); fprintf(fp_cpp, " to[i] = _opnds[i]->clone();\n"); fprintf(fp_cpp, " }\n"); + fprintf(fp_cpp, " // Do not increment node index counter, since node reuses my index\n"); + fprintf(fp_cpp, " Compile* C = Compile::current();\n"); + fprintf(fp_cpp, " C->set_unique(C->unique() - 1);\n"); fprintf(fp_cpp, "}\n"); } fprintf(fp_cpp, "\n"); diff --git a/test/hotspot/jtreg/compiler/regalloc/TestNodeRegArrayOverflow.java b/test/hotspot/jtreg/compiler/regalloc/TestNodeRegArrayOverflow.java new file mode 100644 index 00000000000..281524cc13f --- /dev/null +++ b/test/hotspot/jtreg/compiler/regalloc/TestNodeRegArrayOverflow.java @@ -0,0 +1,599 @@ +/* + * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +package compiler.regalloc; + +/** + * @test + * @bug 8317507 + * @summary Test that C2's PhaseRegAlloc::_node_regs (a post-register-allocation + * mapping from machine nodes to assigned registers) does not overflow + * in the face of a program with a high-density of CISC spilling + * candidate nodes. + * @run main/othervm -Xcomp -XX:CompileOnly=compiler.regalloc.TestNodeRegArrayOverflow::testWithCompilerUnrolling + -XX:CompileCommand=dontinline,compiler.regalloc.TestNodeRegArrayOverflow::dontInline + compiler.regalloc.TestNodeRegArrayOverflow compiler + * @run main/othervm -Xcomp -XX:CompileOnly=compiler.regalloc.TestNodeRegArrayOverflow::testWithManualUnrolling + -XX:CompileCommand=dontinline,compiler.regalloc.TestNodeRegArrayOverflow::dontInline + compiler.regalloc.TestNodeRegArrayOverflow manual + */ + +public class TestNodeRegArrayOverflow { + + static int dontInline() { + return 0; + } + + static float testWithCompilerUnrolling(float inc) { + int i = 0, j = 0; + // This non-inlined method call causes 'inc' to be spilled. + float f = dontInline(); + // This two-level reduction loop is unrolled 512 times, which is + // requested by the SLP-specific unrolling analysis, but not vectorized. + // Because 'inc' is spilled, each of the unrolled AddF nodes is + // CISC-spill converted (PhaseChaitin::fixup_spills()). Before the fix, + // this causes the unique node index counter (Compile::_unique) to grow + // beyond the size of the node register array + // (PhaseRegAlloc::_node_regs), and leads to overflow when accessed for + // nodes that are created later (e.g. during the peephole phase). + while (i++ < 128) { + for (j = 0; j < 16; j++) { + f += inc; + } + } + return f; + } + + // This test reproduces the same failure as 'testWithCompilerUnrolling' + // without relying on loop transformations. + static float testWithManualUnrolling(float inc) { + int i = 0, j = 0; + float f = dontInline(); + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + f += inc; + return f; + } + + public static void main(String[] args) { + switch (args[0]) { + case "compiler": + testWithCompilerUnrolling(0); + break; + case "manual": + testWithManualUnrolling(0); + break; + default: + throw new IllegalArgumentException("Invalid mode: " + args[0]); + } + } +}