CVP doesn't care about the order of blocks visited, but by using a pre-order traversal over the graph we can a) not visit unreachable blocks and b) optimize as we go so that analysis of later blocks produce slightly more precise results.
I noticed this via inspection and don't have a concrete example which points to the issue.
llvm-svn: 290760
There were two problems with the initial fix.
1. The added tests flushed out that we misconfigured _LIBCPP_EXPLICIT with GCC.
2. Because the boolean type was a member function template it caused weird link
errors. I'm assuming due to the vague linkage rules. This time the bool type
is a non-template member function pointer. That seems to have fixed the
failing tests. Plus it will end up generating less symbols overall, since
the bool type is no longer per instantiation.
original commit message below
-----------------------------
std::basic_ios has an operator bool(). In C++11 and later
it is explicit, and only allows contextual implicit conversions.
However explicit isn't available in C++03 which causes std::istream (et al)
to have an implicit conversion to int. This can easily cause ambiguities
when calling operator<< and operator>>.
This patch uses a "bool-like" type in C++03 to work around this. The
"bool-like" type is an arbitrary pointer to member function type. It
will not convert to either int or void*, but will convert to bool.
llvm-svn: 290754
std::basic_ios has an operator bool(). In C++11 and later
it is explicit, and only allows contextual implicit conversions.
However explicit isn't available in C++03 which causes std::istream (et al)
to have an implicit conversion to int. This can easily cause ambiguities
when calling operator<< and operator>>.
This patch uses a "bool-like" type in C++03 to work around this. The
"bool-like" type is an arbitrary pointer to member function type. It
will not convert to either int or void*, but will convert to bool.
llvm-svn: 290750
The bug was introduced in r289619.
Reviewers: Mehdi Amini
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D28134
llvm-svn: 290749
Back in r240527 I added a knob to prevent thread-unsafe functions from
being exposed. mblen(), mbtowc() and wctomb() were also added to this
list, as the latest issue of POSIX doesn't require these functions to be
thread-safe.
It turns out that the only circumstance in which these functions are not
thread-safe is in case they are used in combination with state-dependent
character sets (e.g., Shift-JIS). According to Austin Group Bug 708,
these character sets "[...] are mostly a relic of the past and which
were never supported on most POSIX systems".
Though in many cases the use of these functions can be prevented by
using the reentrant counterparts, they are the only functions that allow
you to query whether the locale's character set is state-dependent. This
means that omitting these functions removes actual functionality.
Let's be a bit less pedantic and drop the guards around these functions.
Links:
http://austingroupbugs.net/view.php?id=708http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2037.htm
Reviewed by: ericwf
Differential Revision: https://reviews.llvm.org/D21436
llvm-svn: 290748
I have a created a new check for clang tidy: misc-string-compare. This will check for incorrect usage of std::string::compare when used to check equality or inequality of string instead of the string equality or inequality operators.
Example:
```
std::string str1, str2;
if (str1.compare(str2)) {
}
```
Reviewers: hokein, aaron.ballman, alexfh, malcolm.parsons
Subscribers: xazax.hun, Eugene.Zelenko, cfe-commits, malcolm.parsons, Prazek, mgorny, JDevlieghere
Differential Revision: https://reviews.llvm.org/D27210
llvm-svn: 290747
I remove one extra line, but because annoyingly llvm-lit does not
clean the output directory before running the test, it didn't fail
locally (the file was present from a previous run).
llvm-svn: 290740
This is similar to the allocfn case - if an alloca is not captured, then it's
necessarily thread-local.
Differential Revision: https://reviews.llvm.org/D28170
llvm-svn: 290738
Summary:
The current loop complete unroll algorithm checks if unrolling complete will reduce the runtime by a certain percentage. If yes, it will apply a fixed boosting factor to the threshold (by discounting cost). The problem for this approach is that the threshold abruptly. This patch makes the boosting factor a function of runtime reduction percentage, capped by a fixed threshold. In this way, the threshold changes continuously.
The patch also simplified the code by reducing one parameter in UP.
The patch only affects code-gen of two speccpu2006 benchmark:
445.gobmk binary size decreases 0.08%, no performance change.
464.h264ref binary size increases 0.24%, no performance change.
Reviewers: mzolotukhin, chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D26989
llvm-svn: 290737
Some incoming changes in ThinLTO will break this test.
Instead of relying on the heuristic to import, we
force the importing to happen with llvm-link.
llvm-svn: 290736
"Changed" doesn't actually change within the loop, so there's
no reason to keep track of it - we always return false during
analysis and true after the transformation is made.
llvm-svn: 290735
We correctly canonicalized (add (sext x), (sext y)) to (sext (add x, y))
where possible. However, we didn't perform the same canonicalization
for zexts or for muls.
llvm-svn: 290733
This moves the exit block and insertion point computation to be eager,
instead of after seeing the first scalar we can promote.
The cost is relatively small (the computation happens anyway, see discussion
on D28147), and the code is easier to follow, and can bail out earlier
if there's a catchswitch present.
llvm-svn: 290729
We would check whether we have a prehader *or* dedicated exit blocks,
and go into the promotion loop. Then, for each alias set we'd check
if we have a preheader *and* dedicated exit blocks, and bail if not.
Instead, bail immediately if we don't have both.
llvm-svn: 290728
We want to recompute LCSSA only when we actually promoted a value.
This means we only need to look at changes made by promotion when
deciding whether to recompute it or not, not at regular sinking/hoisting.
(This was what the code was documented as doing, just not what it did)
Hopefully NFC.
llvm-svn: 290726
This patch is to implement sema and parsing for 'target teams distribute parallel for’ pragma.
Differential Revision: https://reviews.llvm.org/D28160
llvm-svn: 290725
Edit for voice, and also add examples. In particular, add an
explanation for why you might want to specialize IntrusiveRefCntPtrInfo,
which is not obvious.
llvm-svn: 290720
Summary:
This class is unnecessary.
Its comment indicated that it was a compile error to allocate an
instance of a class that inherits from RefCountedBaseVPTR on the stack.
This may have been true at one point, but it's not today.
Moreover you really do not want to allocate *any* refcounted object on
the stack, vptrs or not, so if we did have a way to prevent these
objects from being stack-allocated, we'd want to apply it to regular
RefCountedBase too, obviating the need for a separate RefCountedBaseVPTR
class.
It seems that the main way RefCountedBaseVPTR provides safety is by
making its subclass's destructor virtual. This may have been helpful at
one point, but these days clang will emit an error if you define a class
with virtual functions that inherits from RefCountedBase but doesn't
have a virtual destructor.
Reviewers: compnerd, dblaikie
Subscribers: cfe-commits, klimek, llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D28162
llvm-svn: 290717
Summary: Previously we type-punned through a union, which is not safe.
Reviewers: rnk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D28161
llvm-svn: 290715
This reverts commit r290694. It broke sanitizer tests on Win64. I'll
probably bring this back, but the jump tables will just live in .text
like they do for MSVC.
llvm-svn: 290714
This fixes the issue exposed in PR31393, where we weren't trying
sufficiently hard to diagnose bad TBAA metadata.
This does reduce the variety in the error messages we print out, but I
think the tradeoff of verifying more, simply and quickly overrules the
need for more helpful error messags here.
llvm-svn: 290713
Sebastian Pop