Add a common parent `ConstantData` to the constants that have no
operands. These are guaranteed to represent abstract data that is in no
way tied to a specific Module.
This is a good cleanup on its own. It also makes it simpler to disallow
RAUW (and factor away use-lists) on these constants in the future. (I
have some experimental patches that make RAUW illegal on ConstantData,
and they seem to catch a bunch of bugs...)
llvm-svn: 261464
COFF doesn't have sections with mergeable contents. Instead, each
constant pool entry ends up in a COMDAT section. The linker, when
choosing between COMDAT sections, doesn't choose the max alignment of
the two sections. You just get whatever alignment was on the section.
If one constant needed a higher alignment in one object file from
another one, then we will get into trouble if the linker chooses the
lower alignment one.
Instead, lets promote the alignment of the constant pool entry to make
sure we don't use an under aligned constant with an instruction which
assumed otherwise.
This fixes PR26680.
llvm-svn: 261462
If a header map file is corrupt, the strings in the string table may not
be null-terminated. The logic here previously relied on `MemoryBuffer`
always being null-terminated, but this isn't actually guaranteed by the
class AFAICT. Moreover, we're seeing a lot of crash traces at calls to
`strlen()` inside of `lookupFilename()`, so something is going wrong
there.
Instead, use `strnlen()` to get the length, and check for corruption.
Also remove code paths that could call `StringRef(nullptr)`. r261459
made these rather obvious (although they'd been there all along).
llvm-svn: 261461
This way it's easy to change HeaderMapImpl::getString() to return a
StringRef.
There's a slight change here, because I used `errs()` instead of
`dbgs()`. But `dbgs()` is more appropriate for a dump method.
llvm-svn: 261456
Add a simple test for `HeaderMap::lookupFileName()`. I'm planning to
add better error checking in a moment, and I'll add more tests like this
then.
llvm-svn: 261455
The stack pointer is bumped when there is a frame pointer or when there
are static-size objects, but was only getting written back when there
were static-size objects.
llvm-svn: 261453
TailDuplicate can run on either on SSA code or non-SSA code, as indicated to
it by MRI->isSSA() ("PreRegAlloc" here). TailDuplicate does extra work to
preserve SSA invariants when it duplicates code. This patch makes it skip
some of this extra work in the case where the code is not in SSA form.
llvm-svn: 261450
Check up front whether the header map buffer has space for all of its
declared buckets.
There was already a check in `getBucket()`, but it had UB (comparing
pointers that were outside of objects in the error path) and was
insufficient (only checking for a single byte of the relevant bucket).
I fixed the check, moved it to `checkHeader()`, and left a fixed version
behind as an assertion.
llvm-svn: 261449
If the number of buckets is not a power of two, immediately recognize
the header map as corrupt, rather than waiting for the first lookup. I
converted the later check to an assert.
llvm-svn: 261448
The patch has a necessary call to a function inside an assert. Which is fine
when you have asserts turned on. Not so much when they're off. Sorry about
the regression.
llvm-svn: 261447
Split the implementation of `HeaderMap` into `HeaderMapImpl` so that we
can write unit tests that don't depend on the `FileManager`, and then
write a few tests that cover the types of corrupt header maps already
detected.
This also moves type and constant definitions from HeaderMap.cpp to
HeaderMapTypes.h so that the test can access them.
llvm-svn: 261446
This patch corresponds to review:
http://reviews.llvm.org/D17294
It ensures that whatever block we are emitting the prologue/epilogue into, we
have the necessary scratch registers. It takes away the hard-coded register
numbers for use as scratch registers as registers that are guaranteed to be
available in the function prologue/epilogue are not guaranteed to be available
within the function body. Since we shrink-wrap, the prologue/epilogue may end
up in the function body.
llvm-svn: 261441
As discussed on PR24580, this patch adds some (more to come) initial fast-isel codegen tests to match the IR generated in clang/test/CodeGen/sse41-builtins.c
llvm-svn: 261438
Fixed a bug introduced by D16683 when a binary shuffle is simplified to a unary shuffle (with undef/zero sentinel mask indices) - if this resulted in only the second input being used combineX86ShuffleChain failed to take this into account and still referenced the first input.
llvm-svn: 261434
First small step towards fixing PR26667 - we need to ensure that combineX86ShuffleChain only gets called with a valid shuffle input node (a similar issue was found in D17041).
llvm-svn: 261433
the algorithm easily degrades into quadratic memory and time complexity.
The easiest example is a long chain of BBs that don't otherwise use a
location. The caching will add an entry for every intermediate block and
limiting the number of results doesn't help as no results are produced
until a definition is found.
Introduce a limit similar to the existing instructions-per-block limit.
This limit counts the total number of blocks checked. If the limit is
reached, entries are considered unknown. The initial value is 1000,
which avoids regressions for normal sized functions while still
limiting edge cases to reasnable memory consumption and execution time.
Differential Revision: http://reviews.llvm.org/D16123
llvm-svn: 261430
No functional change intended. Copying small (<= 64 bits) APInts isn't
expensive but bloats code by generating the slow path everywhere. Moving
doesn't care about the size of the value.
llvm-svn: 261426
It can happen that when we only have 1 more register left in the regsave
area we need to store a value bigger than 1 register and therefore we
go to the overflow area. In this case we have to leave the last slot
in the regsave area unused and keep using overflow area. Do this
by storing a limit value to the used register counter in the overflow block.
Issue diagnosed by and solution tested by Mark Millard!
llvm-svn: 261422
The "const" pointer typedefs such as "__node_const_pointer" and
"__node_base_const_pointer" are identical to their non-const pointer types.
This patch changes all usages of "const" pointer type names to their respective
non-const typedef.
Since "fancy pointers to const" cannot be converted back to a non-const pointer
type according to the allocator requirements it is important that we never
actually use "const" pointers.
Furthermore since "__node_const_pointer" and "__node_pointer" already
name the same type, it's very confusing to use both names. Especially
when defining const/non-const overloads for member functions.
llvm-svn: 261419