It's quite possible to encounter an insertvalue instruction that's more deeply
nested than the value we're looking for, but when that happens we really
mustn't compare beyond the end of the index array.
Since I couldn't see any guarantees about what comparisons std::equal makes, we
probably need to directly check the size beforehand. In practice, I suspect
most std::equal implementations would probably bail early, which would be OK.
But just in case...
rdar://20834485
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236635 91177308-0d34-0410-b5e6-96231b3b80d8
When deciding whether a value comes from the aggregate or inserted value of an
insertvalue instruction, we compare the indices against those of the location
we're interested in. One of the lists needs reversing because the input data is
backwards (so that modifications take place at the end of the SmallVector), but
we were reversing both before leading to incorrect results.
Should fix PR23408
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236457 91177308-0d34-0410-b5e6-96231b3b80d8
All of the cases were just appending from random access iterators to a
vector. Using insert/append can grow the vector to the perfect size
directly and moves the growing out of the loop. No intended functionalty
change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230845 91177308-0d34-0410-b5e6-96231b3b80d8
When processing an array, every Elt has the same layout, it is
useless to recursively call each ComputeLinearIndex on each element.
Just do it once and multiply by the number of elements.
Differential Revision: http://reviews.llvm.org/D6832
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There is no need to pass on TLI separately to the function. As Eric pointed out
the Target Machine already provides everything we need.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213108 91177308-0d34-0410-b5e6-96231b3b80d8
Break out the arguemnts required from SelectionDAG, so that this function can
also be used by FastISel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212844 91177308-0d34-0410-b5e6-96231b3b80d8
If the tail-callee and caller give the same bits via the same signext/zeroext
attribute then a tail-call should be allowed, since the extension has already
been done by the callee.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188159 91177308-0d34-0410-b5e6-96231b3b80d8
This change came about primarily because of two issues in the existing code.
Niether of:
define i64 @test1(i64 %val) {
%in = trunc i64 %val to i32
tail call i32 @ret32(i32 returned %in)
ret i64 %val
}
define i64 @test2(i64 %val) {
tail call i32 @ret32(i32 returned undef)
ret i32 42
}
should be tail calls, and the function sameNoopInput is responsible. The main
problem is that it is completely symmetric in the "tail call" and "ret" value,
but in reality different things are allowed on each side.
For these cases:
1. Any truncation should lead to a larger value being generated by "tail call"
than needed by "ret".
2. Undef should only be allowed as a source for ret, not as a result of the
call.
Along the way I noticed that a mismatch between what this function treats as a
valid truncation and what the backends see can lead to invalid calls as well
(see x86-32 test case).
This patch refactors the code so that instead of being based primarily on
values which it recurses into when necessary, it starts by inspecting the type
and considers each fundamental slot that the backend will see in turn. For
example, given a pathological function that returned {{}, {{}, i32, {}}, i32}
we would consider each "real" i32 in turn, and ask if it passes through
unchanged. This is much closer to what the backend sees as a result of
ComputeValueVTs.
Aside from the bug fixes, this eliminates the recursion that's going on and, I
believe, makes the bulk of the code significantly easier to understand. The
trade-off is the nasty iterators needed to find the real types inside a
returned value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187787 91177308-0d34-0410-b5e6-96231b3b80d8
1) Disallow 'returned' on parameter that is also 'sret' (no sensible semantics, as far as I can tell).
2) Conservatively disallow tail calls through 'returned' parameters that also are 'zext' or 'sext' (for consistency with treatment of other zero-extending and sign-extending operations in tail call position detection...can be revised later to handle situations that can be determined to be safe).
This is a new attribute that is not yet used, so there is no impact.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180118 91177308-0d34-0410-b5e6-96231b3b80d8
Tim Northover
Benjamin Kramer
Eric Christopher
Mehdi Amini
Reid Kleckner
Rafael Espindola
Juergen Ributzka
Craig Topper
Michael Gottesman
Stephen Lin