Merge branch 'ab/pcre-v2'

Update "perl-compatible regular expression" support to enable JIT
and also allow linking with the newer PCRE v2 library.

* ab/pcre-v2:
  grep: add support for PCRE v2
  grep: un-break building with PCRE >= 8.32 without --enable-jit
  grep: un-break building with PCRE < 8.20
  grep: un-break building with PCRE < 8.32
  grep: add support for the PCRE v1 JIT API
  log: add -P as a synonym for --perl-regexp
  grep: skip pthreads overhead when using one thread
  grep: don't redundantly compile throwaway patterns under threading

Documentation/rev-list-options.txt

@@ -91,6 +91,7 @@ endif::git-rev-list[]
 	Consider the limiting patterns to be fixed strings (don't interpret
 	pattern as a regular expression).
 
+-P::
 --perl-regexp::
 	Consider the limiting patterns to be Perl-compatible regular
 	expressions.

Makefile

@@ -29,8 +29,23 @@ all::
 # Perl-compatible regular expressions instead of standard or extended
 # POSIX regular expressions.
 #
-# Define LIBPCREDIR=/foo/bar if your libpcre header and library files are in
+# Currently USE_LIBPCRE is a synonym for USE_LIBPCRE1, define
-# /foo/bar/include and /foo/bar/lib directories.
+# USE_LIBPCRE2 instead if you'd like to use version 2 of the PCRE
+# library. The USE_LIBPCRE flag will likely be changed to mean v2 by
+# default in future releases.
+#
+# When using USE_LIBPCRE1, define NO_LIBPCRE1_JIT if the PCRE v1
+# library is compiled without --enable-jit. We will auto-detect
+# whether the version of the PCRE v1 library in use has JIT support at
+# all, but we unfortunately can't auto-detect whether JIT support
+# hasn't been compiled in in an otherwise JIT-supporting version. If
+# you have link-time errors about a missing `pcre_jit_exec` define
+# this, or recompile PCRE v1 with --enable-jit.
+#
+# Define LIBPCREDIR=/foo/bar if your PCRE header and library files are
+# in /foo/bar/include and /foo/bar/lib directories. Which version of
+# PCRE this points to determined by the USE_LIBPCRE1 and USE_LIBPCRE2
+# variables.
 #
 # Define HAVE_ALLOCA_H if you have working alloca(3) defined in that header.
 #
@@ -1089,13 +1104,29 @@ ifdef NO_LIBGEN_H
 	COMPAT_OBJS += compat/basename.o
 endif
 
-ifdef USE_LIBPCRE
+USE_LIBPCRE1 ?= $(USE_LIBPCRE)
+
+ifneq (,$(USE_LIBPCRE1))
+	ifdef USE_LIBPCRE2
+$(error Only set USE_LIBPCRE1 (or its alias USE_LIBPCRE) or USE_LIBPCRE2, not both!)
+	endif
+
 	BASIC_CFLAGS += -DUSE_LIBPCRE1
-	ifdef LIBPCREDIR
+	EXTLIBS += -lpcre
+
+ifdef NO_LIBPCRE1_JIT
+	BASIC_CFLAGS += -DNO_LIBPCRE1_JIT
+endif
+endif
+
+ifdef USE_LIBPCRE2
+	BASIC_CFLAGS += -DUSE_LIBPCRE2
+	EXTLIBS += -lpcre2-8
+endif
+
+ifdef LIBPCREDIR
 	BASIC_CFLAGS += -I$(LIBPCREDIR)/include
 	EXTLIBS += -L$(LIBPCREDIR)/$(lib) $(CC_LD_DYNPATH)$(LIBPCREDIR)/$(lib)
-	endif
-	EXTLIBS += -lpcre
 endif
 
 ifdef HAVE_ALLOCA_H
@@ -2249,7 +2280,9 @@ GIT-BUILD-OPTIONS: FORCE
 	@echo TAR=\''$(subst ','\'',$(subst ','\'',$(TAR)))'\' >>$@+
 	@echo NO_CURL=\''$(subst ','\'',$(subst ','\'',$(NO_CURL)))'\' >>$@+
 	@echo NO_EXPAT=\''$(subst ','\'',$(subst ','\'',$(NO_EXPAT)))'\' >>$@+
-	@echo USE_LIBPCRE1=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE)))'\' >>$@+
+	@echo USE_LIBPCRE1=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE1)))'\' >>$@+
+	@echo USE_LIBPCRE2=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE2)))'\' >>$@+
+	@echo NO_LIBPCRE1_JIT=\''$(subst ','\'',$(subst ','\'',$(NO_LIBPCRE1_JIT)))'\' >>$@+
 	@echo NO_PERL=\''$(subst ','\'',$(subst ','\'',$(NO_PERL)))'\' >>$@+
 	@echo NO_PTHREADS=\''$(subst ','\'',$(subst ','\'',$(NO_PTHREADS)))'\' >>$@+
 	@echo NO_PYTHON=\''$(subst ','\'',$(subst ','\'',$(NO_PYTHON)))'\' >>$@+

builtin/grep.c

@@ -224,6 +224,7 @@ static void start_threads(struct grep_opt *opt)
 		int err;
 		struct grep_opt *o = grep_opt_dup(opt);
 		o->output = strbuf_out;
+		if (i)
 			o->debug = 0;
 		compile_grep_patterns(o);
 		err = pthread_create(&threads[i], NULL, run, o);
@@ -1170,8 +1171,6 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
 	if (!opt.fixed && opt.ignore_case)
 		opt.regflags |= REG_ICASE;
 
-	compile_grep_patterns(&opt);
-
 	/*
 	 * We have to find "--" in a separate pass, because its presence
 	 * influences how we will parse arguments that come before it.
@@ -1244,12 +1243,23 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
 		num_threads = GREP_NUM_THREADS_DEFAULT;
 	else if (num_threads < 0)
 		die(_("invalid number of threads specified (%d)"), num_threads);
+	if (num_threads == 1)
+		num_threads = 0;
 #else
 	if (num_threads)
 		warning(_("no threads support, ignoring --threads"));
 	num_threads = 0;
 #endif
 
+	if (!num_threads)
+		/*
+		 * The compiled patterns on the main path are only
+		 * used when not using threading. Otherwise
+		 * start_threads() below calls compile_grep_patterns()
+		 * for each thread.
+		 */
+		compile_grep_patterns(&opt);
+
 #ifndef NO_PTHREADS
 	if (num_threads) {
 		if (!(opt.name_only || opt.unmatch_name_only || opt.count)

config.mak.uname

@@ -555,6 +555,7 @@ else
 		NO_GETTEXT =
 		USE_GETTEXT_SCHEME = fallthrough
 		USE_LIBPCRE= YesPlease
+		NO_LIBPCRE1_JIT = UnfortunatelyYes
 		NO_CURL =
 		USE_NED_ALLOCATOR = YesPlease
 	else

configure.ac

@@ -255,21 +255,61 @@ GIT_PARSE_WITH([openssl]))
 # Perl-compatible regular expressions instead of standard or extended
 # POSIX regular expressions.
 #
-# Define LIBPCREDIR=/foo/bar if your libpcre header and library files are in
+# Currently USE_LIBPCRE is a synonym for USE_LIBPCRE1, define
+# USE_LIBPCRE2 instead if you'd like to use version 2 of the PCRE
+# library. The USE_LIBPCRE flag will likely be changed to mean v2 by
+# default in future releases.
+#
+# Define LIBPCREDIR=/foo/bar if your PCRE header and library files are in
 # /foo/bar/include and /foo/bar/lib directories.
 #
 AC_ARG_WITH(libpcre,
-AS_HELP_STRING([--with-libpcre],[support Perl-compatible regexes (default is NO)])
+AS_HELP_STRING([--with-libpcre],[synonym for --with-libpcre1]),
-AS_HELP_STRING([],           [ARG can be also prefix for libpcre library and headers]),
     if test "$withval" = "no"; then
-	USE_LIBPCRE=
+	USE_LIBPCRE1=
     elif test "$withval" = "yes"; then
-	USE_LIBPCRE=YesPlease
+	USE_LIBPCRE1=YesPlease
     else
-	USE_LIBPCRE=YesPlease
+	USE_LIBPCRE1=YesPlease
 	LIBPCREDIR=$withval
 	AC_MSG_NOTICE([Setting LIBPCREDIR to $LIBPCREDIR])
-        dnl USE_LIBPCRE can still be modified below, so don't substitute
+        dnl USE_LIBPCRE1 can still be modified below, so don't substitute
+        dnl it yet.
+	GIT_CONF_SUBST([LIBPCREDIR])
+    fi)
+
+AC_ARG_WITH(libpcre1,
+AS_HELP_STRING([--with-libpcre1],[support Perl-compatible regexes via libpcre1 (default is NO)])
+AS_HELP_STRING([],           [ARG can be also prefix for libpcre library and headers]),
+    if test "$withval" = "no"; then
+	USE_LIBPCRE1=
+    elif test "$withval" = "yes"; then
+	USE_LIBPCRE1=YesPlease
+    else
+	USE_LIBPCRE1=YesPlease
+	LIBPCREDIR=$withval
+	AC_MSG_NOTICE([Setting LIBPCREDIR to $LIBPCREDIR])
+        dnl USE_LIBPCRE1 can still be modified below, so don't substitute
+        dnl it yet.
+	GIT_CONF_SUBST([LIBPCREDIR])
+    fi)
+
+AC_ARG_WITH(libpcre2,
+AS_HELP_STRING([--with-libpcre2],[support Perl-compatible regexes via libpcre2 (default is NO)])
+AS_HELP_STRING([],           [ARG can be also prefix for libpcre library and headers]),
+    if test -n "$USE_LIBPCRE1"; then
+        AC_MSG_ERROR([Only supply one of --with-libpcre1 or --with-libpcre2!])
+    fi
+
+    if test "$withval" = "no"; then
+	USE_LIBPCRE2=
+    elif test "$withval" = "yes"; then
+	USE_LIBPCRE2=YesPlease
+    else
+	USE_LIBPCRE2=YesPlease
+	LIBPCREDIR=$withval
+	AC_MSG_NOTICE([Setting LIBPCREDIR to $LIBPCREDIR])
+        dnl USE_LIBPCRE2 can still be modified below, so don't substitute
         dnl it yet.
 	GIT_CONF_SUBST([LIBPCREDIR])
     fi)
@@ -501,13 +541,11 @@ GIT_CONF_SUBST([NEEDS_SSL_WITH_CRYPTO])
 GIT_CONF_SUBST([NO_OPENSSL])
 
 #
-# Define USE_LIBPCRE if you have and want to use libpcre. Various
+# Handle the USE_LIBPCRE1 and USE_LIBPCRE2 options potentially set
-# commands such as log and grep offer runtime options to use
+# above.
-# Perl-compatible regular expressions instead of standard or extended
-# POSIX regular expressions.
 #
 
-if test -n "$USE_LIBPCRE"; then
+if test -n "$USE_LIBPCRE1"; then
 
 GIT_STASH_FLAGS($LIBPCREDIR)
 
@@ -517,7 +555,22 @@ AC_CHECK_LIB([pcre], [pcre_version],
 
 GIT_UNSTASH_FLAGS($LIBPCREDIR)
 
-GIT_CONF_SUBST([USE_LIBPCRE])
+GIT_CONF_SUBST([USE_LIBPCRE1])
+
+fi
+
+
+if test -n "$USE_LIBPCRE2"; then
+
+GIT_STASH_FLAGS($LIBPCREDIR)
+
+AC_CHECK_LIB([pcre2-8], [pcre2_config_8],
+[USE_LIBPCRE2=YesPlease],
+[USE_LIBPCRE2=])
+
+GIT_UNSTASH_FLAGS($LIBPCREDIR)
+
+GIT_CONF_SUBST([USE_LIBPCRE2])
 
 fi
 

grep.c

@@ -179,22 +179,37 @@ static void grep_set_pattern_type_option(enum grep_pattern_type pattern_type, st
 	case GREP_PATTERN_TYPE_BRE:
 		opt->fixed = 0;
 		opt->pcre1 = 0;
+		opt->pcre2 = 0;
 		break;
 
 	case GREP_PATTERN_TYPE_ERE:
 		opt->fixed = 0;
 		opt->pcre1 = 0;
+		opt->pcre2 = 0;
 		opt->regflags |= REG_EXTENDED;
 		break;
 
 	case GREP_PATTERN_TYPE_FIXED:
 		opt->fixed = 1;
 		opt->pcre1 = 0;
+		opt->pcre2 = 0;
 		break;
 
 	case GREP_PATTERN_TYPE_PCRE:
 		opt->fixed = 0;
+#ifdef USE_LIBPCRE2
+		opt->pcre1 = 0;
+		opt->pcre2 = 1;
+#else
+		/*
+		 * It's important that pcre1 always be assigned to
+		 * even when there's no USE_LIBPCRE* defined. We still
+		 * call the PCRE stub function, it just dies with
+		 * "cannot use Perl-compatible regexes[...]".
+		 */
 		opt->pcre1 = 1;
+		opt->pcre2 = 0;
+#endif
 		break;
 	}
 }
@@ -365,9 +380,22 @@ static void compile_pcre1_regexp(struct grep_pat *p, const struct grep_opt *opt)
 	if (!p->pcre1_regexp)
 		compile_regexp_failed(p, error);
 
-	p->pcre1_extra_info = pcre_study(p->pcre1_regexp, 0, &error);
+	p->pcre1_extra_info = pcre_study(p->pcre1_regexp, PCRE_STUDY_JIT_COMPILE, &error);
 	if (!p->pcre1_extra_info && error)
 		die("%s", error);
+
+#ifdef GIT_PCRE1_USE_JIT
+	pcre_config(PCRE_CONFIG_JIT, &p->pcre1_jit_on);
+	if (p->pcre1_jit_on == 1) {
+		p->pcre1_jit_stack = pcre_jit_stack_alloc(1, 1024 * 1024);
+		if (!p->pcre1_jit_stack)
+			die("Couldn't allocate PCRE JIT stack");
+		pcre_assign_jit_stack(p->pcre1_extra_info, NULL, p->pcre1_jit_stack);
+	} else if (p->pcre1_jit_on != 0) {
+		die("BUG: The pcre1_jit_on variable should be 0 or 1, not %d",
+		    p->pcre1_jit_on);
+	}
+#endif
 }
 
 static int pcre1match(struct grep_pat *p, const char *line, const char *eol,
@@ -378,8 +406,19 @@ static int pcre1match(struct grep_pat *p, const char *line, const char *eol,
 	if (eflags & REG_NOTBOL)
 		flags |= PCRE_NOTBOL;
 
-	ret = pcre_exec(p->pcre1_regexp, p->pcre1_extra_info, line, eol - line,
+#ifdef GIT_PCRE1_USE_JIT
-			0, flags, ovector, ARRAY_SIZE(ovector));
+	if (p->pcre1_jit_on) {
+		ret = pcre_jit_exec(p->pcre1_regexp, p->pcre1_extra_info, line,
+				    eol - line, 0, flags, ovector,
+				    ARRAY_SIZE(ovector), p->pcre1_jit_stack);
+	} else
+#endif
+	{
+		ret = pcre_exec(p->pcre1_regexp, p->pcre1_extra_info, line,
+				eol - line, 0, flags, ovector,
+				ARRAY_SIZE(ovector));
+	}
+
 	if (ret < 0 && ret != PCRE_ERROR_NOMATCH)
 		die("pcre_exec failed with error code %d", ret);
 	if (ret > 0) {
@@ -394,7 +433,15 @@ static int pcre1match(struct grep_pat *p, const char *line, const char *eol,
 static void free_pcre1_regexp(struct grep_pat *p)
 {
 	pcre_free(p->pcre1_regexp);
+#ifdef GIT_PCRE1_USE_JIT
+	if (p->pcre1_jit_on) {
+		pcre_free_study(p->pcre1_extra_info);
+		pcre_jit_stack_free(p->pcre1_jit_stack);
+	} else
+#endif
+	{
 		pcre_free(p->pcre1_extra_info);
+	}
 	pcre_free((void *)p->pcre1_tables);
 }
 #else /* !USE_LIBPCRE1 */
@@ -414,6 +461,127 @@ static void free_pcre1_regexp(struct grep_pat *p)
 }
 #endif /* !USE_LIBPCRE1 */
 
+#ifdef USE_LIBPCRE2
+static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)
+{
+	int error;
+	PCRE2_UCHAR errbuf[256];
+	PCRE2_SIZE erroffset;
+	int options = PCRE2_MULTILINE;
+	const uint8_t *character_tables = NULL;
+	int jitret;
+
+	assert(opt->pcre2);
+
+	p->pcre2_compile_context = NULL;
+
+	if (opt->ignore_case) {
+		if (has_non_ascii(p->pattern)) {
+			character_tables = pcre2_maketables(NULL);
+			p->pcre2_compile_context = pcre2_compile_context_create(NULL);
+			pcre2_set_character_tables(p->pcre2_compile_context, character_tables);
+		}
+		options |= PCRE2_CASELESS;
+	}
+	if (is_utf8_locale() && has_non_ascii(p->pattern))
+		options |= PCRE2_UTF;
+
+	p->pcre2_pattern = pcre2_compile((PCRE2_SPTR)p->pattern,
+					 p->patternlen, options, &error, &erroffset,
+					 p->pcre2_compile_context);
+
+	if (p->pcre2_pattern) {
+		p->pcre2_match_data = pcre2_match_data_create_from_pattern(p->pcre2_pattern, NULL);
+		if (!p->pcre2_match_data)
+			die("Couldn't allocate PCRE2 match data");
+	} else {
+		pcre2_get_error_message(error, errbuf, sizeof(errbuf));
+		compile_regexp_failed(p, (const char *)&errbuf);
+	}
+
+	pcre2_config(PCRE2_CONFIG_JIT, &p->pcre2_jit_on);
+	if (p->pcre2_jit_on == 1) {
+		jitret = pcre2_jit_compile(p->pcre2_pattern, PCRE2_JIT_COMPLETE);
+		if (jitret)
+			die("Couldn't JIT the PCRE2 pattern '%s', got '%d'\n", p->pattern, jitret);
+		p->pcre2_jit_stack = pcre2_jit_stack_create(1, 1024 * 1024, NULL);
+		if (!p->pcre2_jit_stack)
+			die("Couldn't allocate PCRE2 JIT stack");
+		p->pcre2_match_context = pcre2_match_context_create(NULL);
+		if (!p->pcre2_jit_stack)
+			die("Couldn't allocate PCRE2 match context");
+		pcre2_jit_stack_assign(p->pcre2_match_context, NULL, p->pcre2_jit_stack);
+	} else if (p->pcre2_jit_on != 0) {
+		die("BUG: The pcre2_jit_on variable should be 0 or 1, not %d",
+		    p->pcre1_jit_on);
+	}
+}
+
+static int pcre2match(struct grep_pat *p, const char *line, const char *eol,
+		regmatch_t *match, int eflags)
+{
+	int ret, flags = 0;
+	PCRE2_SIZE *ovector;
+	PCRE2_UCHAR errbuf[256];
+
+	if (eflags & REG_NOTBOL)
+		flags |= PCRE2_NOTBOL;
+
+	if (p->pcre2_jit_on)
+		ret = pcre2_jit_match(p->pcre2_pattern, (unsigned char *)line,
+				      eol - line, 0, flags, p->pcre2_match_data,
+				      NULL);
+	else
+		ret = pcre2_match(p->pcre2_pattern, (unsigned char *)line,
+				  eol - line, 0, flags, p->pcre2_match_data,
+				  NULL);
+
+	if (ret < 0 && ret != PCRE2_ERROR_NOMATCH) {
+		pcre2_get_error_message(ret, errbuf, sizeof(errbuf));
+		die("%s failed with error code %d: %s",
+		    (p->pcre2_jit_on ? "pcre2_jit_match" : "pcre2_match"), ret,
+		    errbuf);
+	}
+	if (ret > 0) {
+		ovector = pcre2_get_ovector_pointer(p->pcre2_match_data);
+		ret = 0;
+		match->rm_so = (int)ovector[0];
+		match->rm_eo = (int)ovector[1];
+	}
+
+	return ret;
+}
+
+static void free_pcre2_pattern(struct grep_pat *p)
+{
+	pcre2_compile_context_free(p->pcre2_compile_context);
+	pcre2_code_free(p->pcre2_pattern);
+	pcre2_match_data_free(p->pcre2_match_data);
+	pcre2_jit_stack_free(p->pcre2_jit_stack);
+	pcre2_match_context_free(p->pcre2_match_context);
+}
+#else /* !USE_LIBPCRE2 */
+static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)
+{
+	/*
+	 * Unreachable until USE_LIBPCRE2 becomes synonymous with
+	 * USE_LIBPCRE. See the sibling comment in
+	 * grep_set_pattern_type_option().
+	 */
+	die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
+}
+
+static int pcre2match(struct grep_pat *p, const char *line, const char *eol,
+		regmatch_t *match, int eflags)
+{
+	return 1;
+}
+
+static void free_pcre2_pattern(struct grep_pat *p)
+{
+}
+#endif /* !USE_LIBPCRE2 */
+
 static void compile_fixed_regexp(struct grep_pat *p, struct grep_opt *opt)
 {
 	struct strbuf sb = STRBUF_INIT;
@@ -479,6 +647,11 @@ static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 		return;
 	}
 
+	if (opt->pcre2) {
+		compile_pcre2_pattern(p, opt);
+		return;
+	}
+
 	if (opt->pcre1) {
 		compile_pcre1_regexp(p, opt);
 		return;
@@ -838,6 +1011,8 @@ void free_grep_patterns(struct grep_opt *opt)
 				kwsfree(p->kws);
 			else if (p->pcre1_regexp)
 				free_pcre1_regexp(p);
+			else if (p->pcre2_pattern)
+				free_pcre2_pattern(p);
 			else
 				regfree(&p->regexp);
 			free(p->pattern);
@@ -918,6 +1093,8 @@ static int patmatch(struct grep_pat *p, char *line, char *eol,
 		hit = !fixmatch(p, line, eol, match);
 	else if (p->pcre1_regexp)
 		hit = !pcre1match(p, line, eol, match, eflags);
+	else if (p->pcre2_pattern)
+		hit = !pcre2match(p, line, eol, match, eflags);
 	else
 		hit = !regexec_buf(&p->regexp, line, eol - line, 1, match,
 				   eflags);

grep.h

@@ -3,9 +3,33 @@
 #include "color.h"
 #ifdef USE_LIBPCRE1
 #include <pcre.h>
+#ifdef PCRE_CONFIG_JIT
+#if PCRE_MAJOR >= 8 && PCRE_MINOR >= 32
+#ifndef NO_LIBPCRE1_JIT
+#define GIT_PCRE1_USE_JIT
+#endif
+#endif
+#endif
+#ifndef PCRE_STUDY_JIT_COMPILE
+#define PCRE_STUDY_JIT_COMPILE 0
+#endif
+#if PCRE_MAJOR <= 8 && PCRE_MINOR < 20
+typedef int pcre_jit_stack;
+#endif
 #else
 typedef int pcre;
 typedef int pcre_extra;
+typedef int pcre_jit_stack;
+#endif
+#ifdef USE_LIBPCRE2
+#define PCRE2_CODE_UNIT_WIDTH 8
+#include <pcre2.h>
+#else
+typedef int pcre2_code;
+typedef int pcre2_match_data;
+typedef int pcre2_compile_context;
+typedef int pcre2_match_context;
+typedef int pcre2_jit_stack;
 #endif
 #include "kwset.h"
 #include "thread-utils.h"
@@ -48,7 +72,15 @@ struct grep_pat {
 	regex_t regexp;
 	pcre *pcre1_regexp;
 	pcre_extra *pcre1_extra_info;
+	pcre_jit_stack *pcre1_jit_stack;
 	const unsigned char *pcre1_tables;
+	int pcre1_jit_on;
+	pcre2_code *pcre2_pattern;
+	pcre2_match_data *pcre2_match_data;
+	pcre2_compile_context *pcre2_compile_context;
+	pcre2_match_context *pcre2_match_context;
+	pcre2_jit_stack *pcre2_jit_stack;
+	uint32_t pcre2_jit_on;
 	kwset_t kws;
 	unsigned fixed:1;
 	unsigned ignore_case:1;
@@ -112,6 +144,7 @@ struct grep_opt {
 	int extended;
 	int use_reflog_filter;
 	int pcre1;
+	int pcre2;
 	int relative;
 	int pathname;
 	int null_following_name;

revision.c

@@ -2031,7 +2031,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
 	} else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
 		revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
-	} else if (!strcmp(arg, "--perl-regexp")) {
+	} else if (!strcmp(arg, "--perl-regexp") || !strcmp(arg, "-P")) {
 		revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
 	} else if (!strcmp(arg, "--all-match")) {
 		revs->grep_filter.all_match = 1;

t/t4202-log.sh

@@ -404,8 +404,20 @@ test_expect_success 'log with various grep.patternType configurations & command-
 			--grep="(1|2)" >actual.fixed.short-arg &&
 		git log --pretty=tformat:%s -E \
 			--grep="\|2" >actual.extended.short-arg &&
+		if test_have_prereq PCRE
+		then
+			git log --pretty=tformat:%s -P \
+				--grep="[\d]\|" >actual.perl.short-arg
+		else
+			test_must_fail git log -P \
+				--grep="[\d]\|"
+		fi &&
 		test_cmp expect.fixed actual.fixed.short-arg &&
 		test_cmp expect.extended actual.extended.short-arg &&
+		if test_have_prereq PCRE
+		then
+			test_cmp expect.perl actual.perl.short-arg
+		fi &&
 
 		git log --pretty=tformat:%s --fixed-strings \
 			--grep="(1|2)" >actual.fixed.long-arg &&

t/test-lib.sh

@@ -1020,7 +1020,7 @@ esac
 test -z "$NO_PERL" && test_set_prereq PERL
 test -z "$NO_PTHREADS" && test_set_prereq PTHREADS
 test -z "$NO_PYTHON" && test_set_prereq PYTHON
-test -n "$USE_LIBPCRE1" && test_set_prereq PCRE
+test -n "$USE_LIBPCRE1$USE_LIBPCRE2" && test_set_prereq PCRE
 test -z "$NO_GETTEXT" && test_set_prereq GETTEXT
 
 # Can we rely on git's output in the C locale?