start of a filename, not a filename+length. All clients can produce a
null terminated name, and the system api's require null terminated
strings anyway.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49041 91177308-0d34-0410-b5e6-96231b3b80d8
1) stop using MappedFile.
2) if profitable use the sys::path::MapInFilePages api to
read the file.
3) otherwise fallback to read.
When sys::path::MapInFilePages is implemented, this provides
several benefits:
#1: this avoids fragmenting memory for small files.
#2: this avoids extraneous stat calls when the file size is known.
#3: this only keeps the file descriptor open while reading the
file, not for the duration of the lifetime of the memory
buffer. This fixes a serious clang FD 'leak' problem.
I believe that this will work on a win32 machine, but I don't have
one to test on. I'd appreciate it if someone could check.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49031 91177308-0d34-0410-b5e6-96231b3b80d8
not an mmapped file. This more closely matches its requirements and
provides an implicitly null terminated buffer, something this
routine had to emulate itself before.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49024 91177308-0d34-0410-b5e6-96231b3b80d8
tons of out of date comments (really nothing throws here!) and fixes
some other fairly glaring issues: "size" used to return the size of
the file *and* change it, depending on how you called it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49009 91177308-0d34-0410-b5e6-96231b3b80d8
not marked nounwind, or for all functions when -enable-eh
is set, provided the target supports Dwarf EH.
llvm-gcc generates nounwind in the right places; other FEs
will need to do so also. Given such a FE, -enable-eh should
no longer be needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49006 91177308-0d34-0410-b5e6-96231b3b80d8
when something changes, instead of moving forward. This allows us to
simplify memset lowering, inserting the memset at the end of the range of
stuff we're touching instead of at the start.
This, in turn, allows us to make use of the addressing instructions already
used in the function instead of inserting our own. For example, we now
codegen:
%tmp41 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 0 ; <i8*> [#uses=2]
call void @llvm.memset.i64( i8* %tmp41, i8 -1, i64 8, i32 1 )
instead of:
%tmp20 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 7 ; <i8*> [#uses=1]
%ptroffset = getelementptr i8* %tmp20, i64 -7 ; <i8*> [#uses=1]
call void @llvm.memset.i64( i8* %ptroffset, i8 -1, i64 8, i32 1 )
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48940 91177308-0d34-0410-b5e6-96231b3b80d8
memsets that initialize "structs of arrays" and other store sequences
that are not sequential. This is still only enabled if you pass
-form-memset-from-stores. The flag is not heavily tested and I haven't
analyzed the perf regressions when -form-memset-from-stores is passed
either, but this causes no make check regressions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48909 91177308-0d34-0410-b5e6-96231b3b80d8
In order to handle indexed nodes I had to introduce
a new constructor, and since I was there I factorized
the code in the various load constructors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48894 91177308-0d34-0410-b5e6-96231b3b80d8
nodes. This doesn't currently have much impact the generated code, but it
does produce simpler-looking SelectionDAGs, and consequently
simpler-looking ScheduleDAGs, because there are fewer spurious
dependencies.
In particular, CopyValueToVirtualRegister now uses the entry node as the
input chain dependency for new CopyToReg nodes instead of calling getRoot
and depending on the most recent memory reference.
Also, rename UnorderedChains to PendingExports and pull it up from being
a local variable in SelectionDAGISel::BuildSelectionDAG to being a
member variable of SelectionDAGISel, so that it doesn't have to be
passed around to all the places that need it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48893 91177308-0d34-0410-b5e6-96231b3b80d8
called LimitedSumOfUnscheduledPredsOfSuccs. It terminates the computation
after a given treshold is reached. This new function is always faster, but
brings real wins only on bigger test-cases.
The old function SumOfUnscheduledPredsOfSuccs is left in-place for now and therefore a warning about an unused static function is produced.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48872 91177308-0d34-0410-b5e6-96231b3b80d8
LLVM Value/Use does and MachineRegisterInfo/MachineOperand does.
This allows constant time for all uses list maintenance operations.
The idea was suggested by Chris. Reviewed by Evan and Dan.
Patch is tested and approved by Dan.
On normal use-cases compilation speed is not affected. On very big basic
blocks there are compilation speedups in the range of 15-20% or even better.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48822 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes Bugzilla #1835 (http://llvm.org/bugs/show_bug.cgi?id=1835).
This patched is reviewed by Tanya and Dan. Dan tested and approved it.
The reason for the bad performance of the old algorithm is that it is very naive and scans every
time all nodes of the DAG in the worst case.
This patch introduces a new algorithm based on the paper "Online algorithms
for maintaining the topological order of a directed acyclic graph" by
David J.Pearce and Paul H.J.Kelly. This is the MNR algorithm. It has a
linear time worst-case and performs much better in most situations.
The paper can be found here:
http://fano.ics.uci.edu/cites/Document/Online-algorithms-for-maintaining-the-topological-order-of-a-directed-acyclic-graph.html
The main idea of the new algorithm is to compute the topological ordering of the SNodes in the
DAG and to maintain it even after DAG modifications. The topological ordering allows for very fast
node reachability checks.
Tests on very big input files with tens of thousands of instructions in a BB indicate huge
speed-ups (up to 10x compilation time improvement) compared to the old version.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48817 91177308-0d34-0410-b5e6-96231b3b80d8
llvm's output .s files will go through gcc -std=c99
without triggering preprocesser errors. Approach
suggested by Daveed Vandevoorde.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48808 91177308-0d34-0410-b5e6-96231b3b80d8
other things, this allows the scheduler to unfold a load operand
in the 2008-01-08-SchedulerCrash.ll testcase, so it now successfully
clones the comparison to avoid a pushf+popf.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48777 91177308-0d34-0410-b5e6-96231b3b80d8
Furthermore, double the limit when more than 10% of the callee instructions are vector instructions. Multimedia kernels tend to love inlining.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48725 91177308-0d34-0410-b5e6-96231b3b80d8