the IR going into it and to clean up the IR produced by the vectorizers.
Note that these are *off by default* right now while folks collect data
on whether the performance tradeoff is reasonable.
In a build of the 'opt' binary, I see about 2% compile time regression
due to this change on average. This is in my mind essentially the worst
expected case: very little of the opt binary is going to *benefit* from
these extra passes.
I've seen several benchmarks improve in performance my small amounts due
to running these passes, and there are certain (rare) cases where these
passes make a huge difference by either enabling the vectorizer at all
or by hoisting runtime checks out of the outer loop. My primary
motivation is to prevent people from seeing runtime check overhead in
benchmarks where the existing passes and optimizers would be able to
eliminate that.
I've chosen the sequence of passes based on the kinds of things that
seem likely to be relevant for the code at each stage: rotaing loops for
the vectorizer, finding correlated values, loop invariants, and
unswitching opportunities from any runtime checks, and cleaning up
commonalities exposed by the SLP vectorizer.
I'll be pinging existing threads where some of these issues have come up
and will start new threads to get folks to benchmark and collect data on
whether this is the right tradeoff or we should do something else.
llvm-svn: 219644
This change adds UBSan check to upcasts. Namely, when we
perform derived-to-base conversion, we:
1) check that the pointer-to-derived has suitable alignment
and underlying storage, if this pointer is non-null.
2) if vptr-sanitizer is enabled, and we perform conversion to
virtual base, we check that pointer-to-derived has a matching vptr.
llvm-svn: 219642
This goes with the earlier commit to remove the static destructor from ManagedStatic.cpp by controlling the allocation and de-allocation of the mutex.
Summary: This is part of the ongoing work to remove static constructors and destructors.
Reviewers: chandlerc, rnk
Reviewed By: rnk
Subscribers: rnk, llvm-commits
Differential Revision: http://reviews.llvm.org/D5473
llvm-svn: 219640
We assumed that negation operations of the form (0 - %Z) resulted in a
negative number. This isn't true if %Z was originally negative.
Substituting the negative number into the remainder operation may result
in undefined behavior because the dividend might be INT_MIN.
This fixes PR21256.
llvm-svn: 219639
This patch adds a new llvm_call_once function which is used by the ManagedStatic implementation to safely initialize a global to avoid static construction and destruction.
llvm-svn: 219638
We have a transform that changes:
(x lshr C1) udiv C2
into:
x udiv (C2 << C1)
However, it is unsafe to do so if C2 << C1 discards any of C2's bits.
This fixes PR21255.
llvm-svn: 219634
Summary:
Make Mips fast-isel track the form of AArch64 where practical.
This makes it easier for people to review the code, to borrow similar code, and to see how to eventually move a lot of this
target code for fast-isels into target independent code.
These are just cosmetic changes. Should be no functional difference.
Test Plan:
make check
test-suite for 4 flavors mips32 r1/r2 , -O0/-O2
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: aemerson, llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D5595
llvm-svn: 219633
These need to have normal linkage instead of being static inline as
many libraries expect to be able to declare these and have the linker
find them rather than needing to include the header.
http://mentorembedded.github.io/cxx-abi/abi-eh.html
Also clean up some warnings while I'm here.
Reviewers: jroelofs, kledzik
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D5754
llvm-svn: 219629
Broken parent scope pointers in inlined DIVariables can cause
ensureAbstractVariableIsCreated to insert new abstract scopes, thus
invalidating the iterator in this loop and leading to hard-to-debug
crashes. Useful when manually reducing IR for testcases.
llvm-svn: 219628
Fix order of evaluation bug in DynTypedMatcher::constructVariadic().
If it evaluates right-to-left, the vector gets moved before we read the
kind from it.
llvm-svn: 219624
Summary:
Change r219118 fixed the bug for anyOf and eachOf, but it is still
present for unless.
The variadic wrapper doesn't have enough information to know how to
restrict the type. Different operators handle restrict failures in
different ways.
Reviewers: klimek
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D5731
llvm-svn: 219622
This patch does not change the semantic on it's own. However, the
dependence analysis as well as dce will now use the newest available
access relation for each memory access, thus if at some point the json
importer or any other pass will run before those two and set a new
access relation the behaviour will be different. In general it is
unclear if the dependence analysis and dce should be run on the old or
new access functions anyway. If we need to access the original access
function from the outside later, we can expose the getter again.
Differential Revision: http://reviews.llvm.org/D5707
llvm-svn: 219612
Add option ShortStatementLines to trigger this check only if the statement spans
over at least a given number of lines.
Modifications from the original patch:
merged test/clang-tidy/misc-braces-around-statements-always.cpp into
test/clang-tidy/misc-braces-around-statements.cpp and removed unnecessary
CHECK-NOTs from the tests.
http://reviews.llvm.org/D5642
Patch by Marek Kurdej!
llvm-svn: 219611
Some early revisions of the Cortex-A53 have an erratum (835769) whereby it is
possible for a 64-bit multiply-accumulate instruction in AArch64 state to
generate an incorrect result. The details are quite complex and hard to
determine statically, since branches in the code may exist in some
circumstances, but all cases end with a memory (load, store, or prefetch)
instruction followed immediately by the multiply-accumulate operation.
The safest work-around for this issue is to make the compiler avoid emitting
multiply-accumulate instructions immediately after memory instructions and the
simplest way to do this is to insert a NOP.
This patch implements clang options to enable this workaround in the backend.
The work-around code generation is not enabled by default.
llvm-svn: 219604
Some early revisions of the Cortex-A53 have an erratum (835769) whereby it is
possible for a 64-bit multiply-accumulate instruction in AArch64 state to
generate an incorrect result. The details are quite complex and hard to
determine statically, since branches in the code may exist in some
circumstances, but all cases end with a memory (load, store, or prefetch)
instruction followed immediately by the multiply-accumulate operation.
The safest work-around for this issue is to make the compiler avoid emitting
multiply-accumulate instructions immediately after memory instructions and the
simplest way to do this is to insert a NOP.
This patch implements such work-around in the backend, enabled via the option
-aarch64-fix-cortex-a53-835769.
The work-around code generation is not enabled by default.
llvm-svn: 219603
Summary: [asan-asm-instrumentation] Fixed memory references which includes %rsp as a base or an index register.
Reviewers: eugenis
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5599
llvm-svn: 219602
This patch generates call to "kmpc_push_num_threads(ident_t *loc, kmp_int32 global_tid, kmp_int32 num_threads);" library function before calling "kmpc_fork_call" each time there is an associated "num_threads" clause in the "omp parallel" directive.
Differential Revision: http://reviews.llvm.org/D5145
llvm-svn: 219599
Adds codegen for 'if' clause. Currently only for 'if' clause used with the 'parallel' directive.
If condition evaluates to true, the code executes parallel version of the code by calling __kmpc_fork_call(loc, 1, microtask, captured_struct/*context*/), where loc - debug location, 1 - number of additional parameters after "microtask" argument, microtask - is outlined finction for the code associated with the 'parallel' directive, captured_struct - list of variables captured in this outlined function.
If condition evaluates to false, the code executes serial version of the code by executing the following code:
global_thread_id.addr = alloca i32
store i32 global_thread_id, global_thread_id.addr
zero.addr = alloca i32
store i32 0, zero.addr
kmpc_serialized_parallel(loc, global_thread_id);
microtask(global_thread_id.addr, zero.addr, captured_struct/*context*/);
kmpc_end_serialized_parallel(loc, global_thread_id);
Where loc - debug location, global_thread_id - global thread id, returned by __kmpc_global_thread_num() call or passed as a first parameter in microtask() call, global_thread_id.addr - address of the variable, where stored global_thread_id value, zero.addr - implicit bound thread id (should be set to 0 for serial call), microtask() and captured_struct are the same as in parallel call.
Also this patch checks if the condition is constant and if it is constant it evaluates its value and then generates either parallel version of the code (if the condition evaluates to true), or the serial version of the code (if the condition evaluates to false).
Differential Revision: http://reviews.llvm.org/D4716
llvm-svn: 219597
Sanjay Patel