Dropping unreachable code may reduce use counts on other instructions,
so it's better to do this earlier rather than later.
NFC-ish, may only impact worklist order.
This is safe if the iterator type is a pointer and the comparator is
stateless. The enable_if pattern I'm adding here only uses
array_pod_sort for the default comparator (std::less).
Using array_pod_sort has a potential performance impact, but I didn't
notice anything when testing clang. Sorting doesn't seem to be on the
hot path anywhere in LLVM.
Shrinks Release+Asserts clang by 73k.
Currently, bpf does not specify 128bit alignment in its
layout spec. So for a structure like
struct ipv6_key_t {
unsigned pid;
unsigned __int128 saddr;
unsigned short lport;
};
clang will generate IR type
%struct.ipv6_key_t = type { i32, [12 x i8], i128, i16, [14 x i8] }
Additional padding is to ensure later IR->MIR can generate correct
stack layout with target layout spec.
But it is common practice for a tracing program to be
first compiled with target flag (e.g., x86_64 or aarch64) through
clang to generate IR and then go through llc to generate bpf
byte code. Tracing program often refers to kernel internal
data structures which needs to be compiled with non-bpf target.
But such a compilation model may cause a problem on aarch64.
The bcc issue https://github.com/iovisor/bcc/issues/2827
reported such a problem.
For the above structure, since aarch64 has "i128:128" in its
layout string, the generated IR will have
%struct.ipv6_key_t = type { i32, i128, i16 }
Since bpf does not have "i128:128" in its spec string,
the selectionDAG assumes alignment 8 for i128 and
computes the stack storage size for the above is 32 bytes,
which leads incorrect code later.
The x86_64 does not have this issue as it does not have
"i128:128" in its layout spec as it does permits i128 to
be alignmented at 8 bytes at stack. Its IR type looks like
%struct.ipv6_key_t = type { i32, [12 x i8], i128, i16, [14 x i8] }
The fix here is add i128 support in layout spec, the same as
aarch64. The only downside is we may have less optimal stack
allocation in certain cases since we require 16byte alignment
for i128 instead of 8. But this is probably fine as i128 is
not used widely and in most cases users should already
have proper alignment.
Differential Revision: https://reviews.llvm.org/D76587
There was already a test case for landingpads to handle this case, but I
had forgotten to consider PHI instructions preceding the EH_LABEL in the
landingpad.
PR45261
To make sure that replaced operands get DCEd. This drops one
iteration from gepphigep.ll, which is still not optimal.
This was the last test case performing more than 3 iterations.
NFC-ish, only worklist order should change.
Because this code does not use the IC-aware replaceInstUsesWith()
helper, we need to manually push users to the worklist.
This is NFC-ish, in that it may only change worklist order.
This fixes PR# 45336.
Output sections described in a linker script as NOLOAD with no input sections would be marked as SHT_PROGBITS.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D76981
MC already knows how to emulate the .weak directive (with its ELF
semantics; i.e., an undefined weak symbol resolves to 0, and a defined
weak symbol has lower link precedence than a strong symbol of the same
name) using COFF weak externals. Plumb this through the ASM printer too,
so that definitions marked with __attribute__((weak)) at the language
level (which gets translated to weak linkage at the IR level) have the
corresponding .weak directive emitted. Note that declarations marked
with __attribute__((weak)) at the language level (which translates to
extern_weak at the IR level) already have .weak directives emitted.
Weak*/linkonce* symbols without an associated comdat (in particular, ones
generated with __attribute__((weak)) in C/C++) were earlier emitted as
normal unique globals, as the comdat is required to provide the linkonce
semantics. This change makes sure they are emitted as .weak instead,
allowing other symbols to override them.
Rename the existing coff-weak.ll test to coff-linkonce.ll. I'm not
quite sure what that test covers, since the behavior being tested in it
(the emission of a one_only section) is just a result of passing
-function-sections to llc; the linkonce_odr makes no difference.
Add a new coff-weak.ll which tests the new directive emission.
Based on an previous patch by Shoaib Meenai.
Differential Revision: https://reviews.llvm.org/D44543
The preprocessor reads the whole line even if the first condition of an and is false so this broke when compiling on older gcc versions which don't recognize `__has_builtin`
The LatticeVal alias was introduced to reduce the diff size for the
transition to ValueLatticeElement, which is done now.
This patch removes the unnecessary alias and updates some very verbose
type uses with auto.
This seems to be used in some resource files, e.g.
f3217573d7/include/wx/msw/wx.rc (L28).
MSVC rc.exe and GNU windres both allow any value here, and silently
just truncate to uint16_t range. This just explicitly allows the
-1 value and errors out on others - the same was done for control
IDs in dialogs in c1a67857ba.
Differential Revision: https://reviews.llvm.org/D76951
I added a list of options to configure should someone have issues with
long build time or running out of memory. This was added under common
problems in the getting started section of the documentation.
Reviewed By: Meinersbur, dim, e-leclercq
Differential Revision: https://reviews.llvm.org/D75425
Minor update/fixes to comments for the Attributor pass, and dyn_cast -> cast.
Signed-off-by: Uday Bondhugula <uday@polymagelabs.com>
Differential Revision: https://reviews.llvm.org/D76972
In ObjectFileMachO we construct the symbol table from multiple
sources -- primarily the binary's nlist records, but when the nlist
symbols have been stripped, we would augment those with function
start address from the LC_FUNCTION_STARTS or eh_frame. This patch
adds another source of symbols - the exported symbols that the
dynamic linker, dyld, uses at runtime from its trie structure. This
provides us names and addresses for these functions/data.
This patch removes the code from ParseSymtab that would reject an
empty symbol table / nlist source. It adds a new symbols_added
set which tracks the address of every symbol we've added to the
symtab. We add symbols in most-information-ful order, and before
adding a symbol from less-informational-ful source (e.g.
LC_FUNCTION_STARTS with no function name), we check if that symbol
has already been added.
On targets with thumb code generation, instead of using the 0th bit
in these addresses in FunctionStarts (or now the trie entries), we
use the data field of FunctionStarts (formerly used to track if the
func_start should be added) and a flag for the trie entries to
encode this, and only store the actual addresses in the symbols_seen
and these vectors.
<rdar://problem/50791451>
Differential revision: https://reviews.llvm.org/D76758
This change implements constant folding to constrained versions of
intrinsics, implementing rounding: floor, ceil, trunc, round, rint and
nearbyint.
Differential Revision: https://reviews.llvm.org/D72930
The main purpose of introducing these builtins is to add a range
metadata [1, 1025) on the work group size loaded from dispatch
ptr, which cannot be done by source code.
Differential Revision: https://reviews.llvm.org/D76772
scope.
There are a few contexts in which we assume a name is a template name;
if such a context is one where we should perform an unqualified lookup,
and lookup finds nothing, we would form a dependent template name even
if the name is not dependent. This happens in particular for the lookup
of a pseudo-destructor.
In passing, rename ActOnDependentTemplateName to just ActOnTemplateName
given that we apply it for non-dependent template names too.
Summary:
Commit 5f5fb56c68 ("[compiler-rt] Intercept the uname() function")
broke sanitizer-x86_64-linux and clang-cmake-thumbv7-full-sh (again)
builds:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux/builds/26313http://lab.llvm.org:8011/builders/clang-cmake-thumbv7-full-sh/builds/4324
The reason is that uname() can be called as early as
__pthread_initialize_minimal_internal(). When intercepted, this
triggers ASan initialization, which eventually calls dlerror(), which
in turn uses pthreads, causing all sorts of issues.
Fix by falling back to internal_uname() when interceptor runs before
ASan is initialized. This is only for Linux at the moment.
Reviewers: eugenis, vitalybuka
Reviewed By: eugenis
Subscribers: dberris, #sanitizers, pcc
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D76919
Move test/lib/TestDialect to test/lib/Dialect/Test - makes the dir
structure more uniform.
Signed-off-by: Uday Bondhugula <uday@polymagelabs.com>
Differential Revision: https://reviews.llvm.org/D76677
This patch introduces a utility to separate full tiles from partial
tiles when tiling affine loop nests where trip counts are unknown or
where tile sizes don't divide trip counts. A conditional guard is
generated to separate out the full tile (with constant trip count loops)
into the then block of an 'affine.if' and the partial tile to the else
block. The separation allows the 'then' block (which has constant trip
count loops) to be optimized better subsequently: for eg. for
unroll-and-jam, register tiling, vectorization without leading to
cleanup code, or to offload to accelerators. Among techniques from the
literature, the if/else based separation leads to the most compact
cleanup code for multi-dimensional cases (because a single version is
used to model all partial tiles).
INPUT
affine.for %i0 = 0 to %M {
affine.for %i1 = 0 to %N {
"foo"() : () -> ()
}
}
OUTPUT AFTER TILING W/O SEPARATION
map0 = affine_map<(d0) -> (d0)>
map1 = affine_map<(d0)[s0] -> (d0 + 32, s0)>
affine.for %arg2 = 0 to %M step 32 {
affine.for %arg3 = 0 to %N step 32 {
affine.for %arg4 = #map0(%arg2) to min #map1(%arg2)[%M] {
affine.for %arg5 = #map0(%arg3) to min #map1(%arg3)[%N] {
"foo"() : () -> ()
}
}
}
}
OUTPUT AFTER TILING WITH SEPARATION
map0 = affine_map<(d0) -> (d0)>
map1 = affine_map<(d0) -> (d0 + 32)>
map2 = affine_map<(d0)[s0] -> (d0 + 32, s0)>
#set0 = affine_set<(d0, d1)[s0, s1] : (-d0 + s0 - 32 >= 0, -d1 + s1 - 32 >= 0)>
affine.for %arg2 = 0 to %M step 32 {
affine.for %arg3 = 0 to %N step 32 {
affine.if #set0(%arg2, %arg3)[%M, %N] {
// Full tile.
affine.for %arg4 = #map0(%arg2) to #map1(%arg2) {
affine.for %arg5 = #map0(%arg3) to #map1(%arg3) {
"foo"() : () -> ()
}
}
} else {
// Partial tile.
affine.for %arg4 = #map0(%arg2) to min #map2(%arg2)[%M] {
affine.for %arg5 = #map0(%arg3) to min #map2(%arg3)[%N] {
"foo"() : () -> ()
}
}
}
}
}
The separation is tested via a cmd line flag on the loop tiling pass.
The utility itself allows one to pass in any band of contiguously nested
loops, and can be used by other transforms/utilities. The current
implementation works for hyperrectangular loop nests.
Signed-off-by: Uday Bondhugula <uday@polymagelabs.com>
Differential Revision: https://reviews.llvm.org/D76700
When we see this:
```
%a = COPY $physreg
...
SOMETHING implicit-def $physreg
...
%b = COPY $physreg
```
The two copies are not equivalent, and so we shouldn't perform any folding
on them.
When we have two instructions which use a physical register check that they
define the same virtual register(s) as well.
e.g., if we run into this case
```
%a = COPY $physreg
...
%b = COPY %a
```
we can say that the two copies are the same, and can be folded.
Differential Revision: https://reviews.llvm.org/D76890
Benjamin Kramer