Made the "Getting Started Quickly" material its own section.  I think this makes
the document easier to read.
Added bars after every major section heading (to distinguish them more easily from
sub-section headings).
Renamed C front end to GCC front end, as we now support C and C++.
Updated material to reflect the new autoconf-style object root.
Added material about the llvm/runtime directory and the fact that you need to
install the GCC front end before building LLVM (before, it was optional).

llvm-svn: 9003

are ordered by name, not by slot, so the previous solution wasn't any good.
On a large testcase, this reduces time to parse from 2.17s to 1.58s.

llvm-svn: 9002

llvm-svn: 9001

llvm-svn: 9000

llvm-svn: 8999

llvm-svn: 8998

llvm-svn: 8997

llvm-svn: 8996

llvm-svn: 8995

llvm-svn: 8994

tasty 15% speedup on the testcase from Bill.

llvm-svn: 8993

llvm-svn: 8992

if possible.  This provides a consistent 8.5% speedup.

llvm-svn: 8991

Throw the RawInst class in an anon namespace

llvm-svn: 8990

llvm-svn: 8989

llvm-svn: 8988

llvm-svn: 8987

llvm-svn: 8986

in practice though

llvm-svn: 8985

changes:
  * BytecodeReader::getType(...) used to return a null pointer
    on error.  This was only checked about half the time.  Now we convert
    it to throw an exception, and delete the half that checked for error.
    This was checked in before, but psmith crashed and lost the change :(
  * insertValue no longer returns -1 on error, so callers don't need to
    check for it.
  * Substantial rewrite of InstructionReader.cpp, to use more efficient,
    simpler, data structures.  This provides another 5% speedup.  This also
    makes the code much easier to read and understand.

llvm-svn: 8984

simplifies the control flow a bit.  This provides a small (~3%) speedup,
but it's primarily a cleanup exercise.

llvm-svn: 8983

llvm-svn: 8982

llvm-svn: 8981

This results in no significant speedup, but does provide simpler code

llvm-svn: 8980

new, simpler, ForwardReferences data structure.  This is just the first
simple replacement, subsequent changes will improve the code more.

This simple change improves the performance of loading a file from HDF5
(contributed by Bill) from 2.36s to 1.93s, a 22% improvement.  This
presumably has to do with the fact that we only create ONE placeholder for
a particular forward referenced values, and also may be because the data
structure is much simpler.

llvm-svn: 8979

llvm-svn: 8978

in the bytecode parser.  Before we tried to shoehorn basic blocks into the
"getValue" code path with other types of values.  For a variety of reasons
this was a bad idea, so this patch separates it out into its own data structure.

This simplifies the code, makes it fit in 80 columns, and is also much faster.
In a testcase provided by Bill, which has lots of PHI nodes, this patch speeds
up bytecode parsing from taking 6.9s to taking 2.32s.  More speedups to
follow later.

llvm-svn: 8977

llvm-svn: 8976

 their Makefiles.

llvm-svn: 8975

llvm-svn: 8974

Check for strsignal(), which isn't found everywhere, and sys_siglist,
 which can be used to implement it.

llvm-svn: 8973

llvm-svn: 8972

Bill gave me from 8.69s to 6.90s.

llvm-svn: 8971

llvm-svn: 8969

Add a newline after "Cannot find <library>".

llvm-svn: 8968

llvm-svn: 8967

llvm-svn: 8966

llvm-svn: 8965

to avoid reprocessing PHI nodes needlessly.  This speeds up the big bad PHI
testcase 43%: from 104.9826 to 73.5157s

llvm-svn: 8964

llvm-svn: 8963