This pass is needed to break false dependencies. Without it, unlucky
register assignment can result in wild (5x) swings in
performance. This pass was trying to handle AVX but not getting it
right. AVX doesn't have partial register defs, it has unused register
reads in which the high bits of a source operand are copied into the
unused bits of the dest.
Fixing this requires conservative liveness analysis. This is awkard
because the pass already has its own pseudo-liveness. However, proper
liveness is expensive, and we would like to use a generic utility to
compute it. The fix only invokes liveness on-demand. It is rare to
detect a case that needs undef-read dependence breaking, but when it
happens, it can be needed many times within a very large block.
I think the existing heuristic which uses a register window of 16 is
too conservative for loop-carried false dependencies. If the loop is a
reduction. The out-of-order engine may be able to execute several loop
iterations in parallel. However, I'll leave this tuning exercise for
next time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192635 91177308-0d34-0410-b5e6-96231b3b80d8
Some clients may add block live ins and may track liveness over a
large scope. This guarantees an efficient implementation in all cases
with no memory allocation/deallocation, independent of the number of
target registers. It could be slightly less convenient but is fine in
the expected case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192622 91177308-0d34-0410-b5e6-96231b3b80d8
This can happen when processing command line arguments, which
are often stored as std::string's and later turned into
StringRef's via std::string::data(). Unfortunately this
is not guaranteed to return a null-terminated string
until C++11, causing breakage on platforms that don't do this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192558 91177308-0d34-0410-b5e6-96231b3b80d8
Contains a set of live register (units) and code to move forward and
backward in the schedule while updating the live set.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192481 91177308-0d34-0410-b5e6-96231b3b80d8
This should fix the buildbots.
Original commit message:
[DAGCombiner] Slice a big load in two loads when the element are next to each
other in memory and the target has paired load and performs post-isel loads
combining.
E.g., this optimization will transform something like this:
a = load i64* addr
b = trunc i64 a to i32
c = lshr i64 a, 32
d = trunc i64 c to i32
into:
b = load i32* addr1
d = load i32* addr2
Where addr1 = addr2 +/- sizeof(i32), if the target supports paired load and
performs post-isel loads combining.
One should overload TargetLowering::hasPairedLoad to provide this information.
The default is false.
<rdar://problem/14477220>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192476 91177308-0d34-0410-b5e6-96231b3b80d8
other in memory and the target has paired load and performs post-isel loads
combining.
E.g., this optimization will transform something like this:
a = load i64* addr
b = trunc i64 a to i32
c = lshr i64 a, 32
d = trunc i64 c to i32
into:
b = load i32* addr1
d = load i32* addr2
Where addr1 = addr2 +/- sizeof(i32), if the target supports paired load and
performs post-isel loads combining.
One should overload TargetLowering::hasPairedLoad to provide this information.
The default is false.
<rdar://problem/14477220>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192471 91177308-0d34-0410-b5e6-96231b3b80d8
For NVPTX, this fixes a crash where the emitImplicitDef implementation was expecting physical registers,
while NVPTX uses virtual registers (with a couple of exceptions). Now, the implicit def comment will be
emitted as a true PTX register name. Other targets can use this to customize the output of implicit def
comments.
Fixes PR17519
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192444 91177308-0d34-0410-b5e6-96231b3b80d8
Previously LiveInterval has been used, but having a spill weight and
register number is unnecessary for a register unit.
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This makes the API a bit more natural to use and makes it easier to make
LiveRanges implementation details private.
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LiveRange just manages a list of segments and a list of value numbers
now as LiveInterval did previously, but without having details like spill
weight or a fixed register number.
LiveInterval is now a subclass of LiveRange and simply adds the spill weight
and the register number.
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The Segment struct contains a single interval; multiple instances of this struct
are used to construct a live range, but the struct is not a live range by
itself.
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This reverts commit r192316. The original change introduced circular
dependencies between libTarget and backends. That would broke a build unless
link everything into one big binary.
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template_value are updated to use DIRef.
A paired commit at clang is required due to changes to DIBuilder.
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Making them proper functions defined in the (shared)lib instead of
static inlines defined in the header files makes it possible to
actually distribute a binary compiled against the shared library
without having to worry about getting undefined symbol errors when
calling e.g LLVMInitializeAllTargetInfos because the shared library on
the other system was compiled with different targets.
Differential Revision: http://llvm-reviews.chandlerc.com/D1714
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This fixes repeated -Wmicrosoft warnings when self-hosting clang on
Windows, and gets us real unsigned enum types with MSVC.
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Sadly this loses the checking from AssertingVH, but apparently storing the
end() of a BasicBlock into an AssertingVH has bad consequences as it's not
really an instruction.
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This patch fixes an old FIXME by creating a MCTargetStreamer interface
and moving the target specific functions for ARM, Mips and PPC to it.
The ARM streamer is still declared in a common place because it is
used from lib/CodeGen/ARMException.cpp, but the Mips and PPC are
completely hidden in the corresponding Target directories.
I will send an email to llvmdev with instructions on how to use this.
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Bitcasting everything to i8* won't work. Autoupgrade the old
intrinsic declarations to use the new mangling.
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Support for exception handling in the legacy JIT was removed in r181354 and
this code was dead since then.
Thanks to Yaron Keren for noticing it.
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