6940701: Don't align loops in stubs for Niagara sparc
Summary: Don't align loops in stubs for Niagara sparc since NOPs are expensive.
Reviewed-by: twisti, never
/*
* Copyright 1997-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
*/
# include "incls/_precompiled.incl"
# include "incls/_vm_version_sparc.cpp.incl"
int VM_Version::_features = VM_Version::unknown_m;
const char* VM_Version::_features_str = "";
bool VM_Version::is_niagara1_plus() {
// This is a placeholder until the real test is determined.
return is_niagara1() &&
(os::processor_count() > maximum_niagara1_processor_count());
}
void VM_Version::initialize() {
_features = determine_features();
PrefetchCopyIntervalInBytes = prefetch_copy_interval_in_bytes();
PrefetchScanIntervalInBytes = prefetch_scan_interval_in_bytes();
PrefetchFieldsAhead = prefetch_fields_ahead();
// Allocation prefetch settings
intx cache_line_size = L1_data_cache_line_size();
if( cache_line_size > AllocatePrefetchStepSize )
AllocatePrefetchStepSize = cache_line_size;
if( FLAG_IS_DEFAULT(AllocatePrefetchLines) )
AllocatePrefetchLines = 3; // Optimistic value
assert( AllocatePrefetchLines > 0, "invalid value");
if( AllocatePrefetchLines < 1 ) // set valid value in product VM
AllocatePrefetchLines = 1; // Conservative value
AllocatePrefetchDistance = allocate_prefetch_distance();
AllocatePrefetchStyle = allocate_prefetch_style();
assert(AllocatePrefetchDistance % AllocatePrefetchStepSize == 0, "invalid value");
UseSSE = 0; // Only on x86 and x64
_supports_cx8 = has_v9();
if (is_niagara1()) {
// Indirect branch is the same cost as direct
if (FLAG_IS_DEFAULT(UseInlineCaches)) {
FLAG_SET_DEFAULT(UseInlineCaches, false);
}
#ifdef _LP64
// Single issue niagara1 is slower for CompressedOops
// but niagaras after that it's fine.
if (!is_niagara1_plus()) {
if (FLAG_IS_DEFAULT(UseCompressedOops)) {
FLAG_SET_ERGO(bool, UseCompressedOops, false);
}
}
// 32-bit oops don't make sense for the 64-bit VM on sparc
// since the 32-bit VM has the same registers and smaller objects.
Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
#endif // _LP64
#ifdef COMPILER2
// Indirect branch is the same cost as direct
if (FLAG_IS_DEFAULT(UseJumpTables)) {
FLAG_SET_DEFAULT(UseJumpTables, true);
}
// Single-issue, so entry and loop tops are
// aligned on a single instruction boundary
if (FLAG_IS_DEFAULT(InteriorEntryAlignment)) {
FLAG_SET_DEFAULT(InteriorEntryAlignment, 4);
}
if (is_niagara1_plus() && FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
// Use smaller prefetch distance on N2
FLAG_SET_DEFAULT(AllocatePrefetchDistance, 256);
}
#endif
if (FLAG_IS_DEFAULT(OptoLoopAlignment)) {
FLAG_SET_DEFAULT(OptoLoopAlignment, 4);
}
}
// Use hardware population count instruction if available.
if (has_hardware_popc()) {
if (FLAG_IS_DEFAULT(UsePopCountInstruction)) {
FLAG_SET_DEFAULT(UsePopCountInstruction, true);
}
}
char buf[512];
jio_snprintf(buf, sizeof(buf), "%s%s%s%s%s%s%s%s%s%s%s%s",
(has_v8() ? ", has_v8" : ""),
(has_v9() ? ", has_v9" : ""),
(has_hardware_popc() ? ", popc" : ""),
(has_vis1() ? ", has_vis1" : ""),
(has_vis2() ? ", has_vis2" : ""),
(is_ultra3() ? ", is_ultra3" : ""),
(is_sun4v() ? ", is_sun4v" : ""),
(is_niagara1() ? ", is_niagara1" : ""),
(is_niagara1_plus() ? ", is_niagara1_plus" : ""),
(!has_hardware_mul32() ? ", no-mul32" : ""),
(!has_hardware_div32() ? ", no-div32" : ""),
(!has_hardware_fsmuld() ? ", no-fsmuld" : ""));
// buf is started with ", " or is empty
_features_str = strdup(strlen(buf) > 2 ? buf + 2 : buf);
#ifndef PRODUCT
if (PrintMiscellaneous && Verbose) {
tty->print("Allocation: ");
if (AllocatePrefetchStyle <= 0) {
tty->print_cr("no prefetching");
} else {
if (AllocatePrefetchLines > 1) {
tty->print_cr("PREFETCH %d, %d lines of size %d bytes", AllocatePrefetchDistance, AllocatePrefetchLines, AllocatePrefetchStepSize);
} else {
tty->print_cr("PREFETCH %d, one line", AllocatePrefetchDistance);
}
}
if (PrefetchCopyIntervalInBytes > 0) {
tty->print_cr("PrefetchCopyIntervalInBytes %d", PrefetchCopyIntervalInBytes);
}
if (PrefetchScanIntervalInBytes > 0) {
tty->print_cr("PrefetchScanIntervalInBytes %d", PrefetchScanIntervalInBytes);
}
if (PrefetchFieldsAhead > 0) {
tty->print_cr("PrefetchFieldsAhead %d", PrefetchFieldsAhead);
}
}
#endif // PRODUCT
}
void VM_Version::print_features() {
tty->print_cr("Version:%s", cpu_features());
}
int VM_Version::determine_features() {
if (UseV8InstrsOnly) {
NOT_PRODUCT(if (PrintMiscellaneous && Verbose) tty->print_cr("Version is Forced-V8");)
return generic_v8_m;
}
int features = platform_features(unknown_m); // platform_features() is os_arch specific
if (features == unknown_m) {
features = generic_v9_m;
warning("Cannot recognize SPARC version. Default to V9");
}
if (UseNiagaraInstrs) {
if (is_niagara1(features)) {
// Happy to accomodate...
} else {
NOT_PRODUCT(if (PrintMiscellaneous && Verbose) tty->print_cr("Version is Forced-Niagara");)
features = niagara1_m;
}
} else {
if (is_niagara1(features) && !FLAG_IS_DEFAULT(UseNiagaraInstrs)) {
NOT_PRODUCT(if (PrintMiscellaneous && Verbose) tty->print_cr("Version is Forced-Not-Niagara");)
features &= ~niagara1_unique_m;
} else {
// Happy to accomodate...
}
}
return features;
}
static int saved_features = 0;
void VM_Version::allow_all() {
saved_features = _features;
_features = all_features_m;
}
void VM_Version::revert() {
_features = saved_features;
}
unsigned int VM_Version::calc_parallel_worker_threads() {
unsigned int result;
if (is_niagara1_plus()) {
result = nof_parallel_worker_threads(5, 16, 8);
} else {
result = nof_parallel_worker_threads(5, 8, 8);
}
return result;
}