Summary:
As added initially, statepoints required their call targets to be a
constant pointer null if ``numPatchBytes`` was non-zero. This turns out
to be a problem ergonomically, since there is no way to mark patchable
statepoints as calling a (readable) symbolic value.
This change remove the restriction of requiring ``null`` call targets
for patchable statepoints, and changes PlaceSafepoints to maintain the
symbolic call target through its transformation.
Reviewers: reames, swaroop.sridhar
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11550
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243502 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
If a scale or a base register can be rewritten as "Zext({A,+,1})" then
LSR will now consider a formula of that form in its normal cost
computation.
Depends on D9180
Reviewers: qcolombet, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9181
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243348 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Was D9784: "Remove loop variant range check when induction variable is
strictly increasing"
This change re-implements D9784 with the two differences:
1. It does not use SCEVExpander and does not generate new
instructions. Instead, it does a quick local search for existing
`llvm::Value`s that it needs when modifying the `icmp`
instruction.
2. It is more general -- it deals with both increasing and decreasing
induction variables.
I've added all of the tests included with D9784, and two more.
As an example on what this change does (copied from D9784):
Given C code:
```
for (int i = M; i < N; i++) // i is known not to overflow
if (i < 0) break;
a[i] = 0;
}
```
This transformation produces:
```
for (int i = M; i < N; i++)
if (M < 0) break;
a[i] = 0;
}
```
Which can be unswitched into:
```
if (!(M < 0))
for (int i = M; i < N; i++)
a[i] = 0;
}
```
I went back and forth on whether the top level logic should live in
`SimplifyIndvar::eliminateIVComparison` or be put into its own
routine. Right now I've put it under `eliminateIVComparison` because
even though the `icmp` is not *eliminated*, it no longer is an IV
comparison. I'm open to putting it in its own helper routine if you
think that is better.
Reviewers: reames, nicholas, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11278
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243331 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change generalizes the implicit null checks pass to work with
instructions that don't have any explicit register defs. This lets us
use X86's `cmp` against memory as faulting load instructions.
Reviewers: reames, JosephTremoulet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11286
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242703 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Before this change ImplicitNullChecks would only pick loads of the form:
```
test Reg, Reg
jz elsewhere
fallthrough:
movl 32(Reg), Reg2
```
but not (say)
```
test Reg, Reg
jz elsewhere
fallthrough:
inc Reg3
movl 32(Reg), Reg2
```
This change teaches ImplicitNullChecks to look through "unrelated"
instructions like `inc Reg3` when searching for a load instruction
to convert to a trapping load.
Reviewers: atrick, JosephTremoulet, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11044
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241850 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
In RewriteLoopExitValues, before expanding out an SCEV expression using
SCEVExpander, try to see if an existing LLVM IR expression already
computes the value we're interested in. If so use that existing
expression.
Apart from reducing IndVars' reliance on the rest of the compilation
pipeline, this also prevents IndVars from concluding some expressions as
"high cost" when they're not. For instance,
`InductiveRangeCheckElimination` often emits code of the following form:
```
len = umin(len_A, len_B)
loop:
...
if (i++ < len)
goto loop
outside_loop:
use(i)
```
`SCEVExpander` refuses to rewrite the use of `i` in `outside_loop`,
since it thinks the value of `i` on loop exit, `len`, is a high cost
expansion since it contains an `umax` in it. With this change,
`IndVars` can see that it can re-use `len` instead of creating a new
expression to compute `umin(len_A, len_B)`.
I considered putting this cleverness in `SCEVExpander`, but I was
worried that it may then have a deterimental effect on other passes
that use it. So I decided it was better to just do this in the one
place where it seems like an obviously good idea, with the intent of
generalizing later if needed.
Reviewers: atrick, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10782
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241838 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This allows the "if (Statepoint SP = Statepoint(I))" idiom.
(I don't think this change needs review, this was uploaded to
phabricator to provide context for later dependent changes.)
Differential Revision: http://reviews.llvm.org/D10629
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241232 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Introduce a simple accessor to get the gc_result hanging off of a
statepoint.
(I don't think this change needs review, this was uploaded to
phabricator to provide context for later dependent changes.)
Differential Revision: http://reviews.llvm.org/D10627
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241231 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
r240039 adds a test case to check that CallGraph does the right thing
with respect to non-leaf intrinsics like statepoint and patchpoint.
This ports the same test case to LazyCallGraph. LazyCallGraph already
does the right thing with respect to escaping function pointers so there
is no need to change any code.
Reviewers: chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10582
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241226 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change introduces a !make.implicit metadata that allows the
frontend to pre-select the set of explicit null checks that will be
considered for transformation into implicit null checks.
The reason for not using profiling data instead of !make.implicit is
explained in the change to `FaultMaps.rst`.
Reviewers: atrick, reames, pgavlin, JosephTremoulet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10824
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241116 91177308-0d34-0410-b5e6-96231b3b80d8
implicit-null-check-negative.ll had a missing 2>&1. Fix this, and
remove an incorrect test case that this exposes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240998 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
That way llvm-objdump can rely on it without adding an extra dependency
on CodeGen.
This change duplicates the FaultKind enum and the code that serializes
it to a string. I could not figure out a way to get around this without
adding a new dependency to Object
Reviewers: rafael, ab
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10619
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240364 91177308-0d34-0410-b5e6-96231b3b80d8
I had some unnecessary `typename`s left in after addressing review.
This compiled successfully with clang++ but MSVC reported an error. Fix
the build error by removing the redundant `typename`s.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240307 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Since FunctionMap has llvm::Function pointers as keys, the order in
which the traversal happens can differ from run to run, causing spurious
FileCheck failures. Have CallGraph::print sort the CallGraphNodes by
name before printing them.
Reviewers: bogner, chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10575
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240191 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently intrinsics don't affect the creation of the call graph.
This is not accurate with respect to statepoint and patchpoint
intrinsics -- these do call (or invoke) LLVM level functions.
This change fixes this inconsistency by adding a call to the external
node for call sites that call these non-leaf intrinsics. This coupled
with the fact that these intrinsics also escape the function pointer
they call gives us a conservatively correct call graph.
Reviewers: reames, chandlerc, atrick, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10526
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240039 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
NFC: no one uses AnalyzeBranchPredicate yet.
Add TargetInstrInfo::AnalyzeBranchPredicate and implement for x86. A
later change adding support for page-fault based implicit null checks
depends on this.
Reviewers: reames, ab, atrick
Reviewed By: atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10200
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239742 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
TargetInstrInfo::getLdStBaseRegImmOfs to
TargetInstrInfo::getMemOpBaseRegImmOfs and implement for x86. The
implementation only handles a few easy cases now and will be made more
sophisticated in the future.
This is NFCI: the only user of `getLdStBaseRegImmOfs` (now
`getmemOpBaseRegImmOfs`) is `LoadClusterMotion` and `LoadClusterMotion`
is disabled for x86.
Reviewers: reames, ab, MatzeB, atrick
Reviewed By: MatzeB, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10199
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239741 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This instruction encodes a loading operation that may fault, and a label
to branch to if the load page-faults. The locations of potentially
faulting loads and their "handler" destinations are recorded in a
FaultMap section, meant to be consumed by LLVM's clients.
Nothing generates FAULTING_LOAD_OP instructions yet, but they will be
used in a future change.
The documentation (FaultMaps.rst) needs improvement and I will update
this diff with a more expanded version shortly.
Depends on D10196
Reviewers: rnk, reames, AndyAyers, ab, atrick, pgavlin
Reviewed By: atrick, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10197
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239740 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
canUnrollCompletely takes `unsigned` values for `UnrolledCost` and
`RolledDynamicCost` but is passed in `uint64_t`s that are silently
truncated. Because of this, when `UnrolledSize` is a large integer
that has a small remainder with UINT32_MAX, LLVM tries to completely
unroll loops with high trip counts.
Reviewers: mzolotukhin, chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10293
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239218 91177308-0d34-0410-b5e6-96231b3b80d8
This change is NFC because both the ``break;`` and the fall through end
up returning immediately. However, this helps clarify intent and also
ensures correctness in case more ``case`` blocks are added later.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239172 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Once a gc.statepoint has been rewritten to relocate live references, the
SSA values represent physical pointers instead of logical references.
Logical dereferencability does not imply physical dereferencability and
after RewriteStatepointsForGC has run any attributes that imply
dereferencability of the logical references need to be stripped.
This current approach is conservative, and can be made more precise
later if needed. For starters, we need to strip dereferencable
attributes only from pointers that live in the GC address space.
Reviewers: reames, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10105
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238883 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
A later change that has RewriteStatepointsForGC change function
attributes throughout the module depends on this.
Reviewers: reames, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10104
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238882 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
LLVM's MI level notion of invariant_load is different from LLVM's IR
level notion of invariant_load with respect to dereferenceability. The
IR notion of invariant_load only guarantees that all *non-faulting*
invariant loads result in the same value. The MI notion of invariant
load guarantees that the load can be legally moved to any location
within its containing function. The MI notion of invariant_load is
stronger than the IR notion of invariant_load -- an MI invariant_load is
an IR invariant_load + a guarantee that the location being loaded from
is dereferenceable throughout the function's lifetime.
Reviewers: hfinkel, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10075
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238881 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Introduce dereferenceable, dereferenceable_or_null metadata for loads
with the same semantic as corresponding attributes.
This patch depends on http://reviews.llvm.org/D9253
Patch by Artur Pilipenko!
Reviewers: hfinkel, sanjoy, reames
Reviewed By: sanjoy, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9365
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237720 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Allow hoisting of loads from values marked with dereferenceable_or_null
attribute. For values marked with the attribute perform
context-sensitive analysis to determine whether it's known-non-null or
not.
Patch by Artur Pilipenko!
Reviewers: hfinkel, sanjoy, reames
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9253
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237593 91177308-0d34-0410-b5e6-96231b3b80d8
Transfer the calling convention from the invoke being replaced by
PlaceStatepoints to the new invoke to gc.statepoint created. Add a test
case that would have caught this issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237414 91177308-0d34-0410-b5e6-96231b3b80d8
rL236672 would generate all invoke statepoints with deopt args set to a
list containing the single element "0", instead of an empty list.
Also add a test case that would have caught this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237413 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch teaches the PlaceSafepoints pass about two `CallSite`
function attributes:
* "statepoint-id": if the string value of this attribute can be parsed
as an integer, then it is propagated to the ID parameter of the
statepoint created.
* "statepoint-num-patch-bytes": if the string value of this attribute
can be parsed as an integer, then it is propagated to the `num patch
bytes` parameter of the statepoint created.
This change intentionally does not assert on a malformed value for these
attributes, given that they're not "official" attributes.
Reviewers: reames, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9735
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237286 91177308-0d34-0410-b5e6-96231b3b80d8
Show the two new ID and NumPatchBytes fields in the PlaceSafepoint
examples in Statepoints.rst to avoid confusion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237285 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change adds two new parameters to the statepoint intrinsic, `i64 id`
and `i32 num_patch_bytes`. `id` gets propagated to the ID field
in the generated StackMap section. If the `num_patch_bytes` is
non-zero then the statepoint is lowered to `num_patch_bytes` bytes of
nops instead of a call (the spill and reload code remains unchanged).
A non-zero `num_patch_bytes` is useful in situations where a language
runtime requires complete control over how a call is lowered.
This change brings statepoints one step closer to patchpoints. With
some additional work (that is not part of this patch) it should be
possible to get rid of `TargetOpcode::STATEPOINT` altogether.
PlaceSafepoints generates `statepoint` wrappers with `id` set to
`0xABCDEF00` (the old default value for the ID reported in the stackmap)
and `num_patch_bytes` set to `0`. This can be made more sophisticated
later.
Reviewers: reames, pgavlin, swaroop.sridhar, AndyAyers
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9546
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237214 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The original code inserted new instructions by following a
Create->Remove->ReInsert flow. This patch removes the unnecessary
Remove->ReInsert part by setting up the InsertPoint correctly at the
very beginning. This change does not introduce any functionality change.
Patch by Chen Li!
Reviewers: reames, AndyAyers, sanjoy
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9687
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237070 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch is to rename some variables to CamelCase in gc_relocate
related functions. There is no functionality change.
Patch by Chen Li!
Reviewers: reames, AndyAyers, sanjoy
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9681
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237069 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
In RewriteStatepointsForGC pass, we create a gc_relocate intrinsic for
each relocated pointer, and the gc_relocate has the same type with the
pointer. During the creation of gc_relocate intrinsic, llvm requires to
mangle its type. However, llvm does not support mangling of all possible
types. RewriteStatepointsForGC will hit an assertion failure when it
tries to create a gc_relocate for pointer to vector of pointers because
mangling for vector of pointers is not supported.
This patch changes the way RewriteStatepointsForGC pass creates
gc_relocate. For each relocated pointer, we erase the type of pointers
and create an unified gc_relocate of type i8 addrspace(1)*. Then a
bitcast is inserted to convert the gc_relocate to the correct type. In
this way, gc_relocate does not need to deal with different types of
pointers and the unsupported type mangling is no longer a problem. This
change would also ease further merge when LLVM erases types of pointers
and introduces an unified pointer type.
Some minor changes are also introduced to gc_relocate related part in
InstCombineCalls, CodeGenPrepare, and Verifier accordingly.
Patch by Chen Li!
Reviewers: reames, AndyAyers, sanjoy
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9592
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237009 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
There are several unhandled edge cases in BasicAA's GetLinearExpression
method. This changes fixes outstanding issues, including zext / sext of
a constant with the sign bit set, and the refusal to decompose zexts or
sexts of wrapping arithmetic.
Test Plan: Unit tests added in //q.ext.ll//.
Patch by Nick White.
Reviewers: hfinkel, sanjoy
Reviewed By: hfinkel, sanjoy
Subscribers: sanjoy, llvm-commits, hfinkel
Differential Revision: http://reviews.llvm.org/D6682
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236894 91177308-0d34-0410-b5e6-96231b3b80d8
Renames the original CreateGCStatepoint to CreateGCStatepointCall, and
moves invoke creating functionality from PlaceSafepoints.cpp to
IRBuilder.cpp.
This changes the labels generated for PlaceSafepoints/invokes.ll so use
a regex there to make the basic block labels more resilient.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236672 91177308-0d34-0410-b5e6-96231b3b80d8
statepoint-indirect-return.ll breaks on linux systems. Delete the test
case to make the bots green while I figure out what the right fix is.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236568 91177308-0d34-0410-b5e6-96231b3b80d8
For accessors in the `Statepoint` class, use symbolic constants for
offsets into the argument vector instead of literals. This makes the
code intent clearer and simpler to change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236566 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We default the value argument to nullptr. The only use of the value is
in diagnosePossiblyInvalidConstraint and that seems to be resilient to
it being nullptr.
Reviewers: atrick, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9479
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236555 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The exported class will be used in later change, in
StatepointLowering.cpp. It is still internal to SelectionDAG (not
exported via include/).
Reviewers: reames, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9478
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236554 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently this does not change anything, but change will be used in a
later change to StatepointLowering.cpp
Reviewers: reames, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9477
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236553 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Optimizing these well are especially interesting for IRCE since it
"clamps" values by generating this sort of pattern through SCEV
expressions.
Depends on D9352.
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9353
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236203 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
After this change `MatchSelectPattern` recognizes the following form
of SMIN:
Y >s C ? ~Y : ~C == ~Y <s ~C ? ~Y : ~C = SMIN(~Y, ~C)
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9352
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236202 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
If a pointer is marked as dereferenceable_or_null(N), LLVM assumes it
is either `null` or `dereferenceable(N)` or both. This change only
introduces the attribute and adds a token test case for the `llvm-as`
/ `llvm-dis`. It does not hook up other parts of the optimizer to
actually exploit the attribute -- those changes will come later.
For pointers in address space 0, `dereferenceable(N)` is now exactly
equivalent to `dereferenceable_or_null(N)` && `nonnull`. For other
address spaces, `dereferenceable(N)` is potentially weaker than
`dereferenceable_or_null(N)` && `nonnull` (since we could have a null
`dereferenceable(N)` pointer).
The motivating case for this change is Java (and other managed
languages), where pointers are either `null` or dereferenceable up to
some usually known-at-compile-time constant offset.
Reviewers: rafael, hfinkel
Reviewed By: hfinkel
Subscribers: nicholas, llvm-commits
Differential Revision: http://reviews.llvm.org/D8650
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235132 91177308-0d34-0410-b5e6-96231b3b80d8
Bring function documentation for ScalarEvolutionExpander up to code by
not repeating the function name in the comment documenting
functionality. Reflow the edited comments where needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234847 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Runtime unrolling of loops needs to emit an expression to compute the
loop's runtime trip-count. Avoid runtime unrolling if this computation
will be expensive.
Depends on D8993.
Reviewers: atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8994
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234846 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Teach `isHighCostExpansion` to consider divisions by power-of-two
constants as cheap and add a test case. This change is needed for a new
user of `isHighCostExpansion` that will be added in a subsequent change.
Depends on D8995.
Reviewers: atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8993
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234845 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Move isHighCostExpansion from IndVarSimplify to SCEVExpander. This
exposed function will be used in a subsequent change.
Reviewers: bogner, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8995
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234844 91177308-0d34-0410-b5e6-96231b3b80d8
Clean up a predicate I added in r229731, fix the relevant comment and
add a test case. The earlier version is confusing to read and was also
buggy (probably not a coincidence) till Alexey fixed it in r233881.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234701 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change moves creating calls to `llvm.uadd.with.overflow` from
InstCombine to CodeGenPrep. Combining overflow check patterns into
calls to the said intrinsic in InstCombine inhibits optimization because
it introduces an intrinsic call that not all other transforms and
analyses understand.
Depends on D8888.
Reviewers: majnemer, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8889
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234638 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch adds an enum `OverflowCheckFlavor` and a function
`OptimizeOverflowCheck`. This will allow InstCombine to optimize
overflow checks without directly introducing an intermediate call to the
`llvm.$op.with.overflow` instrinsics.
This specific change is a refactoring and does not intend to change
behavior.
Reviewers: majnemer, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8888
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234388 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change teaches ScalarEvolution::isLoopBackedgeGuardedByCond to look
at edges within the loop body that dominate the latch. We don't do an
exhaustive search for all possible edges, but only a quick walk up the
dom tree.
This re-lands r233447. r233447 was reverted because it caused massive
compile-time regressions. This change has a fix for the same issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233829 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change teaches ScalarEvolution::isLoopBackedgeGuardedByCond to look
at edges within the loop body that dominate the latch. We don't do an
exhaustive search for all possible edges, but only a quick walk up the
dom tree.
Reviewers: atrick, hfinkel
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8627
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233447 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch is an attempt at making `DenseMapIterator`s "fail-fast".
Fail-fast iterators that have been invalidated due to insertion into
the host `DenseMap` deterministically trip an assert (in debug mode)
on access, instead of non-deterministically hitting memory corruption
issues.
Enabling fail-fast iterators breaks the LLVM C++ ABI, so they are
predicated on `LLVM_ENABLE_ABI_BREAKING_CHECKS`.
`LLVM_ENABLE_ABI_BREAKING_CHECKS` by default flips with
`LLVM_ENABLE_ASSERTS`, but can be clamped to ON or OFF using the CMake /
autoconf build system.
Reviewers: chandlerc, dexonsmith, rnk, zturner
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8351
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233310 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
With the introduction of MarkPendingLoopPredicates in r157092, I don't
think the bailout is needed anymore.
Reviewers: atrick, nicholas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8624
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233296 91177308-0d34-0410-b5e6-96231b3b80d8
Sanjoy Das