diff --git a/doc/pcre2_jit_free_unused_memory.3 b/doc/pcre2_jit_free_unused_memory.3 index 7a77997..1a5c0e7 100644 --- a/doc/pcre2_jit_free_unused_memory.3 +++ b/doc/pcre2_jit_free_unused_memory.3 @@ -1,4 +1,4 @@ -.TH PCRE2_JIT_FREE_UNUSED_MEMORY 3 "24 October 2014" "PCRE2 10.00" +.TH PCRE2_JIT_FREE_UNUSED_MEMORY 3 "27 October 2014" "PCRE2 10.00" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH SYNOPSIS @@ -15,7 +15,10 @@ PCRE2 - Perl-compatible regular expressions (revised API) .sp This function frees unused JIT executable memory. The argument is a general context, for custom memory management, or NULL for standard memory management. -FIXME: more detail needed. +JIT memory allocation retains some memory in order to improve future JIT +compilation speed. In low memory conditions, +\fBpcre2_jit_free_unused_memory()\fB can be used to cause this memory to be +freed. .P There is a complete description of the PCRE2 native API in the .\" HREF diff --git a/doc/pcre2jit.3 b/doc/pcre2jit.3 index 5842d1b..cc41eec 100644 --- a/doc/pcre2jit.3 +++ b/doc/pcre2jit.3 @@ -1,11 +1,9 @@ -.TH PCRE2JIT 3 "21 October 2014" "PCRE2 10.00" +.TH PCRE2JIT 3 "27 October 2014" "PCRE2 10.00" .SH NAME PCRE2 - Perl-compatible regular expressions (revised API) .SH "PCRE2 JUST-IN-TIME COMPILER SUPPORT" .rs .sp -FIXME: This needs checking over once JIT support is implemented. -.P Just-in-time compiling is a heavyweight optimization that can greatly speed up pattern matching. However, it comes at the cost of extra processing before the match is performed. Therefore, it is of most benefit when the same pattern is @@ -55,9 +53,12 @@ compiled pattern pointer that was returned by \fBpcre2_compile()\fP, and the second is a set of option bits, which must include at least one of PCRE2_JIT_COMPLETE, PCRE2_JIT_PARTIAL_HARD, or PCRE2_JIT_PARTIAL_SOFT. .P -The returned value from \fBpcre2_jit_compile()\fP is zero on success, or a -negative error code. In particular, PCRE2_ERROR_JIT_BADOPTION is returned if -JIT is not supported or if an unknown options bit is set. +If JIT support is not available, a call to \fBpcre2_jit_comple()\fP does +nothing and returns PCRE2_ERROR_JIT_BADOPTION. Otherwise, the compiled pattern +is passed to the JIT compiler, which turns it into machine code that executes +much faster than the normal interpretive code, but yields exactly the same +results. The returned value from \fBpcre2_jit_compile()\fP is zero on success, +or a negative error code. .P PCRE2_JIT_COMPLETE requests the JIT compiler to generate code for complete matches. If you want to run partial matches using the PCRE2_PARTIAL_HARD or @@ -76,11 +77,6 @@ described in the section entitled .\" below. .P -If JIT support is not available, a call to \fBpcre2_jit_comple()\fP does -nothing and returns FIXME. Otherwise, the compiled pattern is passed to the JIT -compiler, which turns it into machine code that executes much faster than the -normal interpretive code, but yields exactly the same results. -.P There are some \fBpcre2_match()\fP options that are not supported by JIT, and there are also some pattern items that JIT cannot handle. Details are given below. In both cases, matching automatically falls back to the interpretive @@ -296,6 +292,21 @@ No, thanks to Windows. If POSIX threads were used everywhere, we could throw out this complicated API. . . +.SH "FREEING JIT SPECULATIVE MEMORY" +.rs +.sp +.nf +.B void pcre2_jit_free_unused_memory(pcre2_general_context *\fIgcontext\fP); +.fi +.P +The JIT executable allocator does not free all memory when it is possible. +It expects new allocations, and keeps some free memory around to improve +allocation speed. However, in low memory conditions, it might be better to free +all possible memory. You can cause this to happen by calling +pcre2_jit_free_unused_memory(). Its argument is a general context, for custom +memory management, or NULL for standard memory management. +. +. .SH "EXAMPLE CODE" .rs .sp @@ -375,6 +386,6 @@ Cambridge CB2 3QH, England. .rs .sp .nf -Last updated: 21 October 2014 +Last updated: 27 October 2014 Copyright (c) 1997-2014 University of Cambridge. .fi