From: "roger@nextmovesoftware.com" <roger@nextmovesoftware.com>
To: java-patches@gcc.gnu.org, gcc-patches@gcc.gnu.org
Subject: [JAVA PATCH] Builtin support for popcount* and bswap* functions
Date: Mon, 22 Feb 2016 18:13:00 -0000 [thread overview]
Message-ID: <A2FAACD0-FA5D-4C85-82F6-42AEECBF0322@nextmovesoftware.com> (raw)
[-- Attachment #1: Type: text/plain, Size: 1695 bytes --]
The following patch provides builtin support for byte swapping and bit counting.
On suitable hardware, these generate the x86 popcount instructions, as also
generated by the SUN HotSpot JIT/JVM for these method calls.
java.lang.Integer.bitCount -> __builtin_popcount
java.lang.Long.bitCount -> __builtin_popcountl
java.lang.Short.reverseBytes -> __builtin_bswap16
java.lang.Integer.reverseBytes -> __builtin_bswap32
java.lang.Long.reverseBytes -> __builtin_bswap64
New test cases have been added to libjava to double check nothing breaks.
Whist I was there I noticed that the math builtins (many of which I added support for
back in 2003/2004) weren't marked as ECF_LEAF, indicating that they don't/can't
invoke any user specified functions. This has also been fixed in the patch below.
The following patch has been tested on x86_64-pc-linux-gnu with a full make bootstrap
and make check with no new failures/regressions.
Ok for stage1 once it reopens?
Cheers,
Roger
--
Roger Sayle, Ph.D.
CEO and founder
NextMove Software Limited
Registered in England No. 07588305
Registered Office: Innovation Centre (Unit 23), Cambridge Science Park, Cambridge CB4 0EY
2016-02-21 Roger Sayle <roger@nextmovesoftware.com>
gcc/java:
* builtins.c (java_builtins): Use popcount* and bswap* builtins to
implement bitCount() and reverseBytes() methods in java.lang.Integer
and friends.
(initialize_builtins): Annotate math builtins with ECF_LEAF. Call
define_builtin for the new popcount* and bswap* builtins.
libjava:
* testsuite/libjava.lang/BuiltinBitCount.java: New test case.
* testsuite/libjava.lang/BuiltinReverseBytes.java: Likewise.
[-- Attachment #2: patch7b.txt --]
[-- Type: text/plain, Size: 4959 bytes --]
Index: builtins.c
===================================================================
--- builtins.c (revision 233190)
+++ builtins.c (working copy)
@@ -98,6 +98,11 @@
{ { "java.lang.Math" }, { "sin" }, NULL, BUILT_IN_SIN },
{ { "java.lang.Math" }, { "sqrt" }, NULL, BUILT_IN_SQRT },
{ { "java.lang.Math" }, { "tan" }, NULL, BUILT_IN_TAN },
+ { { "java.lang.Integer" }, { "bitCount" }, NULL, BUILT_IN_POPCOUNT },
+ { { "java.lang.Integer" }, { "reverseBytes" }, NULL, BUILT_IN_BSWAP32 },
+ { { "java.lang.Long" }, { "bitCount" }, NULL, BUILT_IN_POPCOUNTL },
+ { { "java.lang.Long" }, { "reverseBytes" }, NULL, BUILT_IN_BSWAP64 },
+ { { "java.lang.Short" }, { "reverseBytes" }, NULL, BUILT_IN_BSWAP16 },
{ { "java.lang.Float" }, { "intBitsToFloat" }, convert_real,
(enum built_in_function) 0 },
{ { "java.lang.Double" }, { "longBitsToDouble" }, convert_real,
@@ -483,6 +488,7 @@
tree double_ftype_double, double_ftype_double_double;
tree float_ftype_float_float;
tree boolean_ftype_boolean_boolean;
+ tree int_ftype_int;
int i;
for (i = 0; java_builtins[i].builtin_code != END_BUILTINS; ++i)
@@ -507,50 +513,77 @@
double_type_node, double_type_node, NULL_TREE);
define_builtin (BUILT_IN_FMOD, "__builtin_fmod",
- double_ftype_double_double, "fmod", ECF_CONST);
+ double_ftype_double_double, "fmod", ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_FMODF, "__builtin_fmodf",
- float_ftype_float_float, "fmodf", ECF_CONST);
+ float_ftype_float_float, "fmodf", ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_ACOS, "__builtin_acos",
double_ftype_double, "_ZN4java4lang4Math4acosEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_ASIN, "__builtin_asin",
double_ftype_double, "_ZN4java4lang4Math4asinEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_ATAN, "__builtin_atan",
double_ftype_double, "_ZN4java4lang4Math4atanEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_ATAN2, "__builtin_atan2",
double_ftype_double_double, "_ZN4java4lang4Math5atan2EJddd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_CEIL, "__builtin_ceil",
double_ftype_double, "_ZN4java4lang4Math4ceilEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_COS, "__builtin_cos",
double_ftype_double, "_ZN4java4lang4Math3cosEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_EXP, "__builtin_exp",
double_ftype_double, "_ZN4java4lang4Math3expEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_FLOOR, "__builtin_floor",
double_ftype_double, "_ZN4java4lang4Math5floorEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_LOG, "__builtin_log",
double_ftype_double, "_ZN4java4lang4Math3logEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_POW, "__builtin_pow",
double_ftype_double_double, "_ZN4java4lang4Math3powEJddd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_SIN, "__builtin_sin",
double_ftype_double, "_ZN4java4lang4Math3sinEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_SQRT, "__builtin_sqrt",
double_ftype_double, "_ZN4java4lang4Math4sqrtEJdd",
- ECF_CONST);
+ ECF_CONST | ECF_LEAF);
define_builtin (BUILT_IN_TAN, "__builtin_tan",
double_ftype_double, "_ZN4java4lang4Math3tanEJdd",
- ECF_CONST);
-
+ ECF_CONST | ECF_LEAF);
+
+ int_ftype_int = build_function_type_list (int_type_node,
+ int_type_node, NULL_TREE);
+
+ define_builtin (BUILT_IN_POPCOUNT, "__builtin_popcount", int_ftype_int,
+ "_ZN4java4lang7Integer8bitCountEJii",
+ ECF_CONST | ECF_LEAF | ECF_NOTHROW);
+ define_builtin (BUILT_IN_BSWAP32, "__builtin_bswap32", int_ftype_int,
+ "_ZN4java4lang7Integer12reverseBytesEJii",
+ ECF_CONST | ECF_LEAF | ECF_NOTHROW);
+
+ define_builtin (BUILT_IN_POPCOUNTL, "__builtin_popcountl",
+ build_function_type_list (int_type_node,
+ long_type_node, NULL_TREE),
+ "_ZN4java4lang4Long8bitCountEJix",
+ ECF_CONST | ECF_LEAF | ECF_NOTHROW);
+ define_builtin (BUILT_IN_BSWAP64, "__builtin_bswap64",
+ build_function_type_list (long_type_node,
+ long_type_node, NULL_TREE),
+ "_ZN4java4lang4Long12reverseBytesEJxx",
+ ECF_CONST | ECF_LEAF | ECF_NOTHROW);
+
+ define_builtin (BUILT_IN_BSWAP16, "__builtin_bswap16",
+ build_function_type_list (short_type_node,
+ short_type_node, NULL_TREE),
+ "_ZN4java4lang5Short12reverseBytesEJss",
+ ECF_CONST | ECF_LEAF | ECF_NOTHROW);
+
boolean_ftype_boolean_boolean
= build_function_type_list (boolean_type_node,
boolean_type_node, boolean_type_node,
[-- Attachment #3: BuiltinBitCount.java --]
[-- Type: application/octet-stream, Size: 1135 bytes --]
class BuiltinBitCount
{
public static int popcount(int x)
{
return Integer.bitCount(x);
}
public static int popcountl(long x)
{
return Long.bitCount(x);
}
public static void main(String[] args)
{
if (Integer.bitCount(0) != 0)
throw new Error();
if (Integer.bitCount(8) != 1)
throw new Error();
if (Integer.bitCount(123456) != 6)
throw new Error();
if (Integer.bitCount(-1) != 32)
throw new Error();
if (Long.bitCount(0) != 0)
throw new Error();
if (Long.bitCount(8) != 1)
throw new Error();
if (Long.bitCount(123456) != 6)
throw new Error();
if (Long.bitCount(-1) != 64)
throw new Error();
if (popcount(0) != 0)
throw new Error();
if (popcount(8) != 1)
throw new Error();
if (popcount(123456) != 6)
throw new Error();
if (popcount(-1) != 32)
throw new Error();
if (popcountl(0) != 0)
throw new Error();
if (popcountl(8) != 1)
throw new Error();
if (popcountl(123456) != 6)
throw new Error();
if (popcountl(-1) != 64)
throw new Error();
}
}
[-- Attachment #4: BuiltinReverseBytes.java --]
[-- Type: application/octet-stream, Size: 1569 bytes --]
class BuiltinReverseBytes
{
public static short bswap16(short x)
{
return Short.reverseBytes(x);
}
public static int bswap32(int x)
{
return Integer.reverseBytes(x);
}
public static long bswap64(long x)
{
return Long.reverseBytes(x);
}
public static void main(String[] args)
{
if (Short.reverseBytes((short)0) != (short)0)
throw new Error();
if (Short.reverseBytes((short)0x1234) != (short)0x3412)
throw new Error();
if (Short.reverseBytes((short)-1) != (short)-1)
throw new Error();
if (Integer.reverseBytes(0) != 0)
throw new Error();
if (Integer.reverseBytes(0x12345678) != 0x78563412)
throw new Error();
if (Integer.reverseBytes(-1) != -1)
throw new Error();
if (Long.reverseBytes(0L) != 0L)
throw new Error();
if (Long.reverseBytes(0x123456789abcde0fL) != 0x0fdebc9a78563412L)
throw new Error();
if (Long.reverseBytes(-1L) != -1L)
throw new Error();
if (bswap16((short)0) != (short)0)
throw new Error();
if (bswap16((short)0x1234) != (short)0x3412)
throw new Error();
if (bswap16((short)-1) != (short)-1)
throw new Error();
if (bswap32(0) != 0)
throw new Error();
if (bswap32(0x12345678) != 0x78563412)
throw new Error();
if (bswap32(-1) != -1)
throw new Error();
if (bswap64(0L) != 0L)
throw new Error();
if (bswap64(0x123456789abcde0fL) != 0x0fdebc9a78563412L)
throw new Error();
if (bswap64(-1L) != -1L)
throw new Error();
}
}
[-- Attachment #5: Type: text/plain, Size: 2 bytes --]
next reply other threads:[~2016-02-22 18:13 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-22 18:13 roger [this message]
2016-02-22 18:16 ` Andrew Haley
2016-05-19 18:09 ` Jeff Law
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=A2FAACD0-FA5D-4C85-82F6-42AEECBF0322@nextmovesoftware.com \
--to=roger@nextmovesoftware.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=java-patches@gcc.gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).