This is a major rewrite of the SelectionDAG switch lowering. The previous code
would lower switches as a binary tre, discovering clusters of cases
suitable for lowering by jump tables or bit tests as it went along. To increase
the likelihood of finding jump tables, the binary tree pivot was selected to
maximize case density on both sides of the pivot.
By not selecting the pivot in the middle, the binary trees would not always
be balanced, leading to performance problems in the generated code.
This patch rewrites the lowering to search for clusters of cases
suitable for jump tables or bit tests first, and then builds the binary
tree around those clusters. This way, the binary tree will always be balanced.
This has the added benefit of decoupling the different aspects of the lowering:
tree building and jump table or bit tests finding are now easier to tweak
separately.
For example, this will enable us to balance the tree based on profile info
in the future.
The algorithm for finding jump tables is O(n^2), whereas the previous algorithm
was O(n log n) for common cases, and quadratic only in the worst-case. This
doesn't seem to be major problem in practice, e.g. compiling a file consisting
of a 10k-case switch was only 30% slower, and such large switches should be rare
in practice. Compiling e.g. gcc.c showed no compile-time difference. If this
does turn out to be a problem, we could limit the search space of the algorithm.
This commit also disables all optimizations during switch lowering in -O0.
Differential Revision: http://reviews.llvm.org/D8649
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235101 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Previously, this was only happening for functions, but because of .insn, objects can also be marked now.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8007
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Required some tweaking of ValueMap to accommodate a move-only value
type. No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235091 91177308-0d34-0410-b5e6-96231b3b80d8
In order to introduce v8.1a-specific entities, Mappers should be aware of SubtargetFeatures available.
This patch introduces refactoring, that will then allow to easily introduce:
- v8.1-specific "pan" PState for PStateMapper (PAN extension)
- v8.1-specific sysregs for SysRegMapper (LOR,VHE extensions)
Reviewers: jmolloy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8496
Patch by Tom Coxon
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235089 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This assembler directive marks the current label as an instruction label in microMIPS and MIPS16.
This initial implementation works only for microMIPS.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8006
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235084 91177308-0d34-0410-b5e6-96231b3b80d8
Fix for test case found by James Molloy - TRUNCATE of constant build vectors can be more simply achieved by simply replacing with a new build vector node with the truncated value type - no need to touch the scalar operands at all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235079 91177308-0d34-0410-b5e6-96231b3b80d8
The only type that isn't an integer, isn't floating point, and isn't
a vector; ladies and gentlemen, the gift that keeps on giving: x86_mmx!
Fixes PR23246.
Original message (reverted in r235062):
[CodeGen] Combine concat_vectors of scalars into build_vector.
Combine something like:
(v8i8 concat_vectors (v2i8 bitcast (i16)) x4)
into:
(v8i8 (bitcast (v4i16 BUILD_VECTOR (i16) x4)))
If any of the scalars are floating point, use that throughout.
Differential Revision: http://reviews.llvm.org/D8948
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235072 91177308-0d34-0410-b5e6-96231b3b80d8
Delete `DIRef<>`, and replace the remaining uses of it with
`TypedDebugNodeRef<>`. To minimize code churn, I've added typedefs from
`MDTypeRef` to `DITypeRef` (etc.).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235071 91177308-0d34-0410-b5e6-96231b3b80d8
Try to appease the build bots. We should write rtdyld test cases for these
to make them testible on other platforms.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235070 91177308-0d34-0410-b5e6-96231b3b80d8
PR23080 is almost finished. With this commit, there's no consequential
API in `DIDescriptor` and its subclasses. What's left?
- Default-constructed to `nullptr`.
- Handy `const_cast<>` (constructed from `const`, but accessors are
non-`const`).
I think the safe way to catch those is to delete the classes and fix
compile errors. That'll be my next step, after I delete the `DITypeRef`
(etc.) wrapper around `MDTypeRef`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235069 91177308-0d34-0410-b5e6-96231b3b80d8
Continuing PR23080, gut `DIType` and its various subclasses, leaving
behind thin wrappers around the pointer types in the new debug info
hierarchy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235064 91177308-0d34-0410-b5e6-96231b3b80d8
The way we split SEH catch-all blocks can leave some dead EH values
behind at -O0. Try to remove them, and if we fail, replace them all with
undef.
Fixes a crash when removing the old unreachable landingpad which is
still used by extractvalue instructions in the catch-all block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235061 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This allows us to get rid of the original unrelocated object file after
we're done processing relocations (but before applying them).
MachO and COFF already do not require this (currently we have temporary hacks
to prevent ownership from being released, but those are brittle and should be
removed soon).
The placeholder mechanism allowed the relocation resolver to look at original
object file to obtain more information that are required to apply the
relocations. This is usually necessary in two cases:
- For relocations targetting sub-word memory locations, there may be pieces
of the instruction at the target address which we should not override.
- Some relocations on some platforms allow an extra addend to be encoded in
their immediate fields.
The problem is that in the second case the information cannot be recovered
after the relocations have been applied once because they will have been
overridden. In the first case we also need to be careful to not use any bits
that aren't fixed and may have been overriden by applying a first relocation.
In the past both have been fixed by just looking at original object file. This
patch attempts to recover the information from the first by looking at the
relocated object file, while the extra addend in the second case is read
upon relocation processing and addend to the regular addend.
I have tested this on X86. Other platforms represent my best understanding
of how those relocations should work, but I may have missed something because
I do not have access to those platforms.
We will keep the ugly workarounds in place for a couple of days, so this commit
can be reverted if it breaks the bots.
Reviewers: petarj, t.p.northover, lhames
Reviewed By: lhames
Subscribers: aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D9028
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Remove the accessors of `DIDerivedType` that downcast to
`MDDerivedType`, shifting the `cast<MDDerivedType>` into the callers.
Also remove `DIType::isValid()`, which is really just a check against
`nullptr` at this point.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235059 91177308-0d34-0410-b5e6-96231b3b80d8
Continuing gutting `DIDescriptor` subclasses; this edition,
`DICompileUnit` and `DIFile`. In the name of PR23080.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235055 91177308-0d34-0410-b5e6-96231b3b80d8
Remove 'inlinedAt:' from MDLocalVariable. Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.
The 'inlinedAt:' field was used by the backend in two ways:
1. To tell the backend whether and into what a variable was inlined.
2. To create a unique id for each inlined variable.
Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).
This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.
If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235050 91177308-0d34-0410-b5e6-96231b3b80d8
Before we start to rely on valid `!dbg` attachments, add a check to the
verifier that `@llvm.dbg.*` intrinsics always have one. Also check that
the `scope:` fields point at the same `MDSubprogram`.
This is in the context of PR22778. The check that the `inlinedAt:`
fields agree has baked for a while (since r234021), so I'll kill [1] the
`MDLocalVariable::getInlinedAt()` field soon.
[1]: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20150330/269387.html
Unfortunately, that means it's impossible to keep the current `Verifier`
checks, which rely on comparing `inlinedAt:` fields. We'll be able to
keep the checks I'm adding here.
If this breaks your out-of-tree testcases, the upgrade script
(add-dbg-to-intrinsics.sh) attached to PR22778 that I used for r235040
might fix them for you.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235048 91177308-0d34-0410-b5e6-96231b3b80d8
Change `DIBuilder::insertDeclare()` and `insertDbgValueIntrinsic()` to
take an `MDLocation*`/`DebugLoc` parameter which it attaches to the
created intrinsic. Assert at creation time that the `scope:` field's
subprogram matches the variable's. There's a matching `clang` commit to
use the API.
The context for this is PR22778, which is removing the `inlinedAt:`
field from `MDLocalVariable`, instead deferring to the `!dbg` location
attached to the debug info intrinsic. The best way to ensure we always
have a `!dbg` attachment is to require one at creation time. I'll be
adding verifier checks next, but this API change is the best way to
shake out frontend bugs.
Note: I added an `llvm_unreachable()` in `bindings/go` and passed in
`nullptr` for the `DebugLoc`. The `llgo` folks will eventually need to
pass a valid `DebugLoc` here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235041 91177308-0d34-0410-b5e6-96231b3b80d8
Add missing `!dbg` attachments to `@llvm.dbg.*` intrinsics. I updated
these using a script (add-dbg-to-intrinsics.sh) that I'll attach to
PR22778 for posterity.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235040 91177308-0d34-0410-b5e6-96231b3b80d8
This avoids emitting code for unreachable landingpad blocks that contain
calls to llvm.eh.actions and indirectbr.
It's also a first step towards unifying the SEH and WinEH lowering
codepaths. I'm keeping the old fan-in lowering of SEH around until the
preparation version works well enough that we can switch over without
breaking existing users.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235037 91177308-0d34-0410-b5e6-96231b3b80d8
signature match the other layers.
This makes it possible to compose other layers (e.g. IRTransformLayer) on top
of CompileOnDemandLayer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235029 91177308-0d34-0410-b5e6-96231b3b80d8
BXJ was incorrectly said to be unsupported in ARMv8-A. It is not
supported in the A64 instruction set, but it is supported in the T32
and A32 instruction sets, because it's listed as an instruction in the
ARM ARM section F7.1.28.
Using SP as an operand to BXJ changed from UNPREDICTABLE to
PREDICTABLE in v8-A. This patch reflects that update as well.
This was found by MCHammer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235024 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
With this patch, SLSR may rewrite
S1: X = B + i * S
S2: Y = B + i' * S
to
S2: Y = X + (i' - i) * S
A secondary improvement: if (i' - i) is a power of 2, emit Y as X + (S << log(i' - i)). (S << log(i' -i)) is in a canonical form and thus more likely GVN'ed than (i' - i) * S.
Test Plan: slsr-add.ll
Reviewers: hfinkel, sanjoy, meheff, broune, eliben
Reviewed By: eliben
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8983
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