Reorganize our CRC source files again.

Now that we use CRC-32C in WAL and the control file, the "traditional" and
"legacy" CRC-32 variants are not used in any frontend programs anymore.
Move the code for those back from src/common to src/backend/utils/hash.

Also move the slicing-by-8 implementation (back) to src/port. This is in
preparation for next patch that will add another implementation that uses
Intel SSE 4.2 instructions to calculate CRC-32C, where available.

11 files changed, 123 insertions, 25 deletions

diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 4075a6f743a..b85a666ca1c 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -1023,8 +1023,8 @@ EndPrepare(GlobalTransaction gxact)
 	TwoPhaseFileHeader *hdr;
 	char		path[MAXPGPATH];
 	StateFileChunk *record;
-	pg_crc32	statefile_crc;
-	pg_crc32	bogus_crc;
+	pg_crc32c	statefile_crc;
+	pg_crc32c	bogus_crc;
 	int			fd;
 
 	/* Add the end sentinel to the list of 2PC records */
@@ -1034,7 +1034,7 @@ EndPrepare(GlobalTransaction gxact)
 	/* Go back and fill in total_len in the file header record */
 	hdr = (TwoPhaseFileHeader *) records.head->data;
 	Assert(hdr->magic == TWOPHASE_MAGIC);
-	hdr->total_len = records.total_len + sizeof(pg_crc32);
+	hdr->total_len = records.total_len + sizeof(pg_crc32c);
 
 	/*
 	 * If the file size exceeds MaxAllocSize, we won't be able to read it in
@@ -1082,7 +1082,7 @@ EndPrepare(GlobalTransaction gxact)
 	 */
 	bogus_crc = ~statefile_crc;
 
-	if ((write(fd, &bogus_crc, sizeof(pg_crc32))) != sizeof(pg_crc32))
+	if ((write(fd, &bogus_crc, sizeof(pg_crc32c))) != sizeof(pg_crc32c))
 	{
 		CloseTransientFile(fd);
 		ereport(ERROR,
@@ -1091,7 +1091,7 @@ EndPrepare(GlobalTransaction gxact)
 	}
 
 	/* Back up to prepare for rewriting the CRC */
-	if (lseek(fd, -((off_t) sizeof(pg_crc32)), SEEK_CUR) < 0)
+	if (lseek(fd, -((off_t) sizeof(pg_crc32c)), SEEK_CUR) < 0)
 	{
 		CloseTransientFile(fd);
 		ereport(ERROR,
@@ -1135,7 +1135,7 @@ EndPrepare(GlobalTransaction gxact)
 	/* If we crash now, we have prepared: WAL replay will fix things */
 
 	/* write correct CRC and close file */
-	if ((write(fd, &statefile_crc, sizeof(pg_crc32))) != sizeof(pg_crc32))
+	if ((write(fd, &statefile_crc, sizeof(pg_crc32c))) != sizeof(pg_crc32c))
 	{
 		CloseTransientFile(fd);
 		ereport(ERROR,
@@ -1223,7 +1223,7 @@ ReadTwoPhaseFile(TransactionId xid, bool give_warnings)
 	int			fd;
 	struct stat stat;
 	uint32		crc_offset;
-	pg_crc32	calc_crc,
+	pg_crc32c	calc_crc,
 				file_crc;
 
 	TwoPhaseFilePath(path, xid);
@@ -1258,14 +1258,14 @@ ReadTwoPhaseFile(TransactionId xid, bool give_warnings)
 
 	if (stat.st_size < (MAXALIGN(sizeof(TwoPhaseFileHeader)) +
 						MAXALIGN(sizeof(TwoPhaseRecordOnDisk)) +
-						sizeof(pg_crc32)) ||
+						sizeof(pg_crc32c)) ||
 		stat.st_size > MaxAllocSize)
 	{
 		CloseTransientFile(fd);
 		return NULL;
 	}
 
-	crc_offset = stat.st_size - sizeof(pg_crc32);
+	crc_offset = stat.st_size - sizeof(pg_crc32c);
 	if (crc_offset != MAXALIGN(crc_offset))
 	{
 		CloseTransientFile(fd);
@@ -1302,7 +1302,7 @@ ReadTwoPhaseFile(TransactionId xid, bool give_warnings)
 	COMP_CRC32C(calc_crc, buf, crc_offset);
 	FIN_CRC32C(calc_crc);
 
-	file_crc = *((pg_crc32 *) (buf + crc_offset));
+	file_crc = *((pg_crc32c *) (buf + crc_offset));
 
 	if (!EQ_CRC32C(calc_crc, file_crc))
 	{
@@ -1545,7 +1545,7 @@ void
 RecreateTwoPhaseFile(TransactionId xid, void *content, int len)
 {
 	char		path[MAXPGPATH];
-	pg_crc32	statefile_crc;
+	pg_crc32c	statefile_crc;
 	int			fd;
 
 	/* Recompute CRC */
@@ -1572,7 +1572,7 @@ RecreateTwoPhaseFile(TransactionId xid, void *content, int len)
 				(errcode_for_file_access(),
 				 errmsg("could not write two-phase state file: %m")));
 	}
-	if (write(fd, &statefile_crc, sizeof(pg_crc32)) != sizeof(pg_crc32))
+	if (write(fd, &statefile_crc, sizeof(pg_crc32c)) != sizeof(pg_crc32c))
 	{
 		CloseTransientFile(fd);
 		ereport(ERROR,
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 5688268c72d..975eac0c22b 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -862,7 +862,7 @@ XLogRecPtr
 XLogInsertRecord(XLogRecData *rdata, XLogRecPtr fpw_lsn)
 {
 	XLogCtlInsert *Insert = &XLogCtl->Insert;
-	pg_crc32	rdata_crc;
+	pg_crc32c	rdata_crc;
 	bool		inserted;
 	XLogRecord *rechdr = (XLogRecord *) rdata->data;
 	bool		isLogSwitch = (rechdr->xl_rmid == RM_XLOG_ID &&
@@ -4179,7 +4179,7 @@ WriteControlFile(void)
 static void
 ReadControlFile(void)
 {
-	pg_crc32	crc;
+	pg_crc32c	crc;
 	int			fd;
 
 	/*
@@ -4681,7 +4681,7 @@ BootStrapXLOG(void)
 	bool		use_existent;
 	uint64		sysidentifier;
 	struct timeval tv;
-	pg_crc32	crc;
+	pg_crc32c	crc;
 
 	/*
 	 * Select a hopefully-unique system identifier code for this installation.
diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c
index 88209c3d163..618f8792f89 100644
--- a/src/backend/access/transam/xloginsert.c
+++ b/src/backend/access/transam/xloginsert.c
@@ -459,7 +459,7 @@ XLogRecordAssemble(RmgrId rmid, uint8 info,
 	XLogRecData *rdt;
 	uint32		total_len = 0;
 	int			block_id;
-	pg_crc32	rdata_crc;
+	pg_crc32c	rdata_crc;
 	registered_buffer *prev_regbuf = NULL;
 	XLogRecData *rdt_datas_last;
 	XLogRecord *rechdr;
diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c
index a4124d90d1b..77be1b8ef3c 100644
--- a/src/backend/access/transam/xlogreader.c
+++ b/src/backend/access/transam/xlogreader.c
@@ -665,7 +665,7 @@ ValidXLogRecordHeader(XLogReaderState *state, XLogRecPtr RecPtr,
 static bool
 ValidXLogRecord(XLogReaderState *state, XLogRecord *record, XLogRecPtr recptr)
 {
-	pg_crc32	crc;
+	pg_crc32c	crc;
 
 	/* Calculate the CRC */
 	INIT_CRC32C(crc);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index ff5ff265e60..82e7d986b42 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -1391,7 +1391,7 @@ typedef struct SnapBuildOnDisk
 
 	/* data not covered by checksum */
 	uint32		magic;
-	pg_crc32	checksum;
+	pg_crc32c	checksum;
 
 	/* data covered by checksum */
 
@@ -1634,7 +1634,7 @@ SnapBuildRestore(SnapBuild *builder, XLogRecPtr lsn)
 	char		path[MAXPGPATH];
 	Size		sz;
 	int			readBytes;
-	pg_crc32	checksum;
+	pg_crc32c	checksum;
 
 	/* no point in loading a snapshot if we're already there */
 	if (builder->state == SNAPBUILD_CONSISTENT)
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index fcd7ba1433a..16ea80bc3a0 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -56,7 +56,7 @@ typedef struct ReplicationSlotOnDisk
 
 	/* data not covered by checksum */
 	uint32		magic;
-	pg_crc32	checksum;
+	pg_crc32c	checksum;
 
 	/* data covered by checksum */
 	uint32		version;
@@ -1075,7 +1075,7 @@ RestoreSlotFromDisk(const char *name)
 	int			fd;
 	bool		restored = false;
 	int			readBytes;
-	pg_crc32	checksum;
+	pg_crc32c	checksum;
 
 	/* no need to lock here, no concurrent access allowed yet */
 
diff --git a/src/backend/utils/adt/tsgistidx.c b/src/backend/utils/adt/tsgistidx.c
index 25132be441a..0a1e6644dd3 100644
--- a/src/backend/utils/adt/tsgistidx.c
+++ b/src/backend/utils/adt/tsgistidx.c
@@ -17,6 +17,7 @@
 #include "access/gist.h"
 #include "access/tuptoaster.h"
 #include "tsearch/ts_utils.h"
+#include "utils/pg_crc.h"
 
 
 #define SIGLENINT  31			/* >121 => key will toast, so it will not work
diff --git a/src/backend/utils/adt/tsquery.c b/src/backend/utils/adt/tsquery.c
index acabd94f08e..2c32ffe5af7 100644
--- a/src/backend/utils/adt/tsquery.c
+++ b/src/backend/utils/adt/tsquery.c
@@ -14,13 +14,13 @@
 
 #include "postgres.h"
 
-#include "common/pg_crc.h"
 #include "libpq/pqformat.h"
 #include "miscadmin.h"
 #include "tsearch/ts_locale.h"
 #include "tsearch/ts_utils.h"
 #include "utils/builtins.h"
 #include "utils/memutils.h"
+#include "utils/pg_crc.h"
 
 
 struct TSQueryParserStateData
diff --git a/src/backend/utils/cache/relmapper.c b/src/backend/utils/cache/relmapper.c
index 48b83516769..c151b92dfc3 100644
--- a/src/backend/utils/cache/relmapper.c
+++ b/src/backend/utils/cache/relmapper.c
@@ -86,7 +86,7 @@ typedef struct RelMapFile
 	int32		magic;			/* always RELMAPPER_FILEMAGIC */
 	int32		num_mappings;	/* number of valid RelMapping entries */
 	RelMapping	mappings[MAX_MAPPINGS];
-	pg_crc32	crc;			/* CRC of all above */
+	pg_crc32c	crc;			/* CRC of all above */
 	int32		pad;			/* to make the struct size be 512 exactly */
 } RelMapFile;
 
@@ -626,7 +626,7 @@ load_relmap_file(bool shared)
 {
 	RelMapFile *map;
 	char		mapfilename[MAXPGPATH];
-	pg_crc32	crc;
+	pg_crc32c	crc;
 	int			fd;
 
 	if (shared)
diff --git a/src/backend/utils/hash/Makefile b/src/backend/utils/hash/Makefile
index 05d347c8563..64eebd1d996 100644
--- a/src/backend/utils/hash/Makefile
+++ b/src/backend/utils/hash/Makefile
@@ -12,6 +12,6 @@ subdir = src/backend/utils/hash
 top_builddir = ../../../..
 include $(top_builddir)/src/Makefile.global
 
-OBJS = dynahash.o hashfn.o
+OBJS = dynahash.o hashfn.o pg_crc.o
 
 include $(top_srcdir)/src/backend/common.mk
diff --git a/src/backend/utils/hash/pg_crc.c b/src/backend/utils/hash/pg_crc.c
new file mode 100644
index 00000000000..74c16184743
--- /dev/null
+++ b/src/backend/utils/hash/pg_crc.c
@@ -0,0 +1,97 @@
+/*-------------------------------------------------------------------------
+ *
+ * pg_crc.c
+ *	  PostgreSQL CRC support
+ *
+ * See Ross Williams' excellent introduction
+ * A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS, available from
+ * http://www.ross.net/crc/download/crc_v3.txt or several other net sites.
+ *
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/hash/pg_crc.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "c.h"
+
+#include "utils/pg_crc.h"
+
+/*
+ * Lookup table for calculating CRC-32 using Sarwate's algorithm.
+ *
+ * This table is based on the polynomial
+ *	x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.
+ * (This is the same polynomial used in Ethernet checksums, for instance.)
+ * Using Williams' terms, this is the "normal", not "reflected" version.
+ */
+const uint32 pg_crc32_table[256] = {
+	0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA,
+	0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
+	0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,
+	0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
+	0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE,
+	0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
+	0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC,
+	0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
+	0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,
+	0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
+	0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940,
+	0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
+	0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116,
+	0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
+	0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
+	0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
+	0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A,
+	0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
+	0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818,
+	0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
+	0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,
+	0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
+	0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C,
+	0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
+	0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2,
+	0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
+	0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,
+	0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
+	0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086,
+	0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
+	0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4,
+	0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
+	0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,
+	0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
+	0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8,
+	0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
+	0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE,
+	0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
+	0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
+	0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
+	0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252,
+	0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
+	0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60,
+	0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
+	0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
+	0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
+	0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04,
+	0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
+	0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A,
+	0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
+	0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,
+	0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
+	0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E,
+	0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
+	0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
+	0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
+	0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,
+	0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
+	0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0,
+	0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
+	0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6,
+	0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
+	0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
+	0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
+};