Summary:
Before this patch call graph is like this in the LoopUnrollPass:
tryToUnrollLoop
ApproximateLoopSize
collectEphemeralValues
/* Use collected ephemeral values */
computeUnrollCount
analyzeLoopUnrollCost
/* Bail out from the analysis if loop contains CallInst */
This patch moves collection of the ephemeral values to the tryToUnrollLoop
function and passes the collected values into both ApproximateLoopsize (as
before) and additionally starts using them in analyzeLoopUnrollCost:
tryToUnrollLoop
collectEphemeralValues
ApproximateLoopSize(EphValues)
/* Use EphValues */
computeUnrollCount(EphValues)
analyzeLoopUnrollCost(EphValues)
/* Ignore ephemeral values - they don't contribute to the final cost */
/* Bail out from the analysis if loop contains CallInst */
Reviewers: mzolotukhin, evstupac, sanjoy
Reviewed By: evstupac
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43931
llvm-svn: 327617
Methods `computeExitLimitFromCondCached` and `computeExitLimitFromCondImpl` take
true and false branches as parameters and only use them for asserts and for identifying
whether true/false branch belongs to the loop (which can be done once earlier). This fact
complicates generalization of exit limit computation logic on guards because the guards
don't have blocks to which they go in case of failure explicitly.
The motivation of this patch is that currently this part of SCEV knows nothing about guards
and only works with explicit branches. As result, it fails to prove that a loop
for (i = 0; i < 100; i++)
guard(i < 10);
exits after 10th iteration, while in the equivalent example
for (i = 0; i < 100; i++)
if (i >= 10) break;
SCEV easily proves this fact. We are going to change it in near future, and this is why
we need to make these methods operate on more abstract level.
This patch refactors this code to get rid of these parameters as meaningless and prepare
ground for teaching these methods to work with guards as well as they work with explicit
branching instructions.
Differential Revision: https://reviews.llvm.org/D44419
llvm-svn: 327615
Patch teaches LLD to print BYTE/SHORT/LONG/QUAD and
location move commands to the map file.
Differential revision: https://reviews.llvm.org/D44004
llvm-svn: 327612
There is no 512 bit addsub instruction, but we partially match it handle fmaddsub matching. We explicitly bail out for 512 bit vectors after failing the fmaddsub match, but we had no test coverage for that bail out.
We might want to consider splitting and using 256 bit instructions instead of the long sequence seen here.
llvm-svn: 327605
Summary:
Some PDB symbols do not have a valid VA or RVA but have Addr by Section and Offset. For example, a variable in thread-local storage has the following properties:
get_addressOffset: 0
get_addressSection: 5
get_lexicalParentId: 2
get_name: g_tls
get_symIndexId: 12
get_typeId: 4
get_dataKind: 6
get_symTag: 7
get_locationType: 2
This change provides a new method to locate line numbers by Section and Offset from those symbols.
Reviewers: zturner, rnk, llvm-commits
Subscribers: asmith, JDevlieghere
Differential Revision: https://reviews.llvm.org/D44407
llvm-svn: 327601
When using:
(lldb) settings set target.source-map ./ /path/to/source
LLDB would fail to set a source file and line breakpoint with:
(lldb) breakpoint set --file /path/to/source/main.c --line 2
Because code in the target was undoing the remapping of "/path/to/source/main.c" to "./main.c" and then it would resolve this path, which would append the current working directory to the path. We don't want to resolve paths that we unmap.
Test case added.
Differential Revision: https://reviews.llvm.org/D44502
llvm-svn: 327600
Use an enum parameter instead of a bool for more control on how the copy elision
functions work. Extract the move initialization code from the move or copy
initialization block.
Patch by: Arthur O'Dwyer
Differential Revision: https://reviews.llvm.org/D43898
llvm-svn: 327598
r327343 changed the handling for CallExpr in a CFG, which prevented lookups for
CallExpr while other Stmt kinds still worked. This change carries over the
necessary bits from Stmt function to CallExpr function.
llvm-svn: 327593
Until we have a better story for putting commands and check lines
in the same file (they're currently ignored), it seems that inline
tests are actually more concise and easier to understand.
Too bad we have still some python boilerplate, but that's not
really substantial so we can live with it.
Thanks to Fred for pointing out and Jim for explaining me how
to use the inline test format.
<rdar://problem/34806516>
llvm-svn: 327592
Adding a Zircon module to clang-tidy for checks specific to the Zircon
kernel, and adding a checker to fuchsia-zx (for zircon) to flag instances
where specific objects are temporarily created.
Differential Revision: https://reviews.llvm.org/D44346
llvm-svn: 327590
Summary:
This variable is largely going unused; aside from reporting number of instructions for in DEBUG builds.
The only use of NumInstructions is in debug output to represent the LoopSize. That value can be can be misleading as it also includes metadata instructions (e.g., DBG_VALUE) which have no real impact. If we do choose to keep this around, we probably should guard it by a DEBUG macro, as it's not used in production builds.
Reviewers: majnemer, congh, rengolin
Reviewed By: rengolin
Subscribers: llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D44495
llvm-svn: 327589
Before the patch:
(lldb) frame var emptyDictionary
(__NSDictionary0 *) emptyDictionary = 0x0000000100304420
After:
(lldb) frame var emptyDictionary
(__NSDictionary0 *) emptyDictionary = 0x0000000100304420 0 key/value pairs
There's nothing much else we can do, as this is always empty by
definition.
<rdar://problem/34806516>
llvm-svn: 327587
These should all be folded. The vector tests need to have
m_AnyZero updated to ignore undef elements, but we need to
be careful not to return the existing value in that case
and unintentionally propagate undef.
llvm-svn: 327585
Summary:
Local values are constants, global addresses, and stack addresses that
can't be folded into the instruction that uses them. For example, when
storing the address of a global variable into memory, we need to
materialize that address into a register.
FastISel doesn't want to materialize any given local value more than
once, so it generates all local value materialization code at
EmitStartPt, which always dominates the current insertion point. This
allows it to maintain a map of local value registers, and it knows that
the local value area will always dominate the current insertion point.
The downside is that local value instructions are always emitted without
a source location. This is done to prevent jumpy line tables, but it
means that the local value area will be considered part of the previous
statement. Consider this C code:
call1(); // line 1
++global; // line 2
++global; // line 3
call2(&global, &local); // line 4
Today we end up with assembly and line tables like this:
.loc 1 1
callq call1
leaq global(%rip), %rdi
leaq local(%rsp), %rsi
.loc 1 2
addq $1, global(%rip)
.loc 1 3
addq $1, global(%rip)
.loc 1 4
callq call2
The LEA instructions in the local value area have no source location and
are treated as being on line 1. Stepping through the code in a debugger
and correlating it with the assembly won't make much sense, because
these materializations are only required for line 4.
This is actually problematic for the VS debugger "set next statement"
feature, which effectively assumes that there are no registers live
across statement boundaries. By sinking the local value code into the
statement and fixing up the source location, we can make that feature
work. This was filed as https://bugs.llvm.org/show_bug.cgi?id=35975 and
https://crbug.com/793819.
This change is obviously not enough to make this feature work reliably
in all cases, but I felt that it was worth doing anyway because it
usually generates smaller, more comprehensible -O0 code. I measured a
0.12% regression in code generation time with LLC on the sqlite3
amalgamation, so I think this is worth doing.
There are some special cases worth calling out in the commit message:
1. local values materialized for phis
2. local values used by no-op casts
3. dead local value code
Local values can be materialized for phis, and this does not show up as
a vreg use in MachineRegisterInfo. In this case, if there are no other
uses, this patch sinks the value to the first terminator, EH label, or
the end of the BB if nothing else exists.
Local values may also be used by no-op casts, which adds the register to
the RegFixups table. Without reversing the RegFixups map direction, we
don't have enough information to sink these instructions.
Lastly, if the local value register has no other uses, we can delete it.
This comes up when fastisel tries two instruction selection approaches
and the first materializes the value but fails and the second succeeds
without using the local value.
Reviewers: aprantl, dblaikie, qcolombet, MatzeB, vsk, echristo
Subscribers: dotdash, chandlerc, hans, sdardis, amccarth, javed.absar, zturner, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D43093
llvm-svn: 327581
Get rid of the "; mem:" suffix and use the one we use in MIR: ":: (load 2)".
rdar://38163529
Differential Revision: https://reviews.llvm.org/D42377
llvm-svn: 327580
Since there is no reliable way to change the AST depth of this test by supported stack size
of the test environment, remove this test for now.
llvm-svn: 327578
If we have an invariant.start with no corresponding invariant.end, then the memory location becomes invariant indefinitely after the invariant.start. As a result, anything dominated by the start is guaranteed to see the value the memory location had when the invariant.start executed.
This patch adds an AvailableInvariants table which tracks the generation a particular memory location became invariant and then uses that information to allow value forwarding that would otherwise be disallowed by potentially aliasing stores. (Reminder: In EarlyCSE everything clobbers everything by default.)
This should be compatible with the MemorySSA variant, but design is generational. We can and should add first class support for invariant.start within MemorySSA at a later time. I took a quick look at doing so, but probably need some input from a MemorySSA expert.
Differential Revision: https://reviews.llvm.org/D43716
llvm-svn: 327577
This reverts commit r327566, it breaks
test/ExecutionEngine/OrcMCJIT/test-global-ctors.ll.
The test doesn't crash with a stack trace, unfortunately. It merely
returns 1 as the exit code.
ASan didn't produce a report, and I reproduced this on my Linux machine
and Windows box.
llvm-svn: 327576
As shown in:
https://bugs.llvm.org/show_bug.cgi?id=27151
...the existing fold could miscompile when X is NaN.
The fold was also dependent on 'ninf' but that's not necessary.
From IEEE-754 (with default rounding which we can assume for these opcodes):
"When the sum of two operands with opposite signs (or the difference of two
operands with like signs) is exactly zero, the sign of that sum (or difference)
shall be +0...However, x + x = x − (−x) retains the same sign as x even when
x is zero."
llvm-svn: 327575
I definitely didn't run the tests before committing :(
Most of these tests failed because the LLD map file output changed,
moving the functions from the main text section to a new per-function
section.
ICF also started to fire in a few cases, leading to new layouts.
llvm-svn: 327571
Optionally allow the order of restoring the callee-saved registers in the
epilogue to be reversed.
The flag -reverse-csr-restore-seq generates the following code:
```
stp x26, x25, [sp, #-64]!
stp x24, x23, [sp, #16]
stp x22, x21, [sp, #32]
stp x20, x19, [sp, #48]
; [..]
ldp x24, x23, [sp, #16]
ldp x22, x21, [sp, #32]
ldp x20, x19, [sp, #48]
ldp x26, x25, [sp], #64
ret
```
Note how the CSRs are restored in the same order as they are saved.
One exception to this rule is the last `ldp`, which allows us to merge
the stack adjustment and the ldp into a post-index ldp. This is done by
first generating:
ldp x26, x27, [sp]
add sp, sp, #64
which gets merged by the arm64 load store optimizer into
ldp x26, x25, [sp], #64
The flag is disabled by default.
llvm-svn: 327569
Andrew V. Tischenko