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Fix grammar. Bold face feature points. 

llvm-svn: 68720
This commit is contained in:
Ted Kremenek 2009-04-09 18:22:40 +00:00
parent 4adfee4ff7
commit 11e13fae69
1 changed files with 7 additions and 8 deletions
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15
clang/docs/PTHInternals.html
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@ -33,9 +33,8 @@ system headers (e.g., Mac OS/X).</p>
<p>Clang supports an implementation of precompiled headers known as
<em>pre-tokenized headers</em> (PTH). Clang's pre-tokenized headers support most
of same interfaces as GCC's pre-compiled headers (as well as others) but are
completely different in their implementation. This first describes the
interface for using PTH and then briefly elaborates on their design and
implementation.</p>
completely different in their implementation. This first describes the interface
for using PTH and then briefly elaborates on its design and implementation.</p>
<h2>Using Pretokenized Headers with <tt>clang</tt></h2>
@ -142,13 +141,13 @@ header files was motivated by the following factors:<p>
<ul>
<li><p><em>Language independence</em>: PTH files work with any language that
<li><p><b>Language independence</b>: PTH files work with any language that
Clang's lexer can handle, including C, Objective-C, and (in the early stages)
C++. This means development on language features at the parsing level or above
(which is basically almost all interesting pieces) does not require PTH to be
modified.</p></li>
<li><em>Simple design</em>: Relatively speaking, PTH has a simple design and
<li><b>Simple design</b>: Relatively speaking, PTH has a simple design and
implementation, making it easy to test. Further, because the machinery for PTH
resides at the lower-levels of the Clang library stack it is fairly
straightforward to profile and optimize.</li>
@ -160,7 +159,7 @@ against) the PTH design in Clang yields several attractive features:</p>
<ul>
<li><p><em>Architecture independence</em>: In contrast to GCC's PCH files (and
<li><p><b>Architecture independence</b>: In contrast to GCC's PCH files (and
those of several other compilers), Clang's PTH files are architecture
independent, requiring only a single PTH file when building an program for
multiple architectures.</p>
@ -174,7 +173,7 @@ cache of header files, a single PTH file can be safely used when compiling for
multiple architectures. This can also reduce compile times because only a single
PTH file needs to be generated during a build instead of several.</p></li>
<li><p><em>Reduced memory pressure</em>: Similar to GCC,
<li><p><b>Reduced memory pressure</b>: Similar to GCC,
Clang reads PTH files via the use of memory mapping (i.e., <tt>mmap</tt>).
Clang, however, memory maps PTH files as read-only, meaning that multiple
invocations of <tt>clang-cc</tt> can share the same pages in memory from a
@ -183,7 +182,7 @@ also modifies those pages in memory, incurring the copy-on-write costs. The
read-only nature of PTH can greatly reduce memory pressure for builds involving
multiple cores, thus improving overall scalability.</p></li>
<li><p><em>Fast generation</em>: PTH files can be generated in a small fraction
<li><p><b>Fast generation</b>: PTH files can be generated in a small fraction
of the time needed to generate GCC's PCH files. Since PTH/PCH generation is a
serial operation that typically blocks progress during a build, faster
generation time leads to improved processor utilization with parallel builds on