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tons of out of date comments (really nothing throws here!)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
