Commit Graph

910 Commits

Author SHA1 Message Date
Nikita Popov 9e45146721 [CodeGen] Fix element type for sret argument
Fix a mistake in 9bf917394eba3ba4df77cc17690c6d04f4e9d57f: sret
arguments use ConvertType, not ConvertTypeForMem, see the handling
in CodeGenTypes::GetFunctionType().

This fixes fp-matrix-pragma.c on s390x.
2021-12-17 16:13:28 +01:00
Nikita Popov 9bf917394e [CodeGen] Avoid more pointer element type accesses 2021-12-17 12:11:50 +01:00
Mike Rice 2d0bf14397 [clang] Cleanup unneeded Function nullptr checks [NFC]
Add an assert and avoid unneeded checks of Fn in
CodeGenFunction::GenerateCode.

Differential Revision: https://reviews.llvm.org/D115817
2021-12-16 08:28:10 -08:00
Andrew Browne 7c004c2bc9 Revert "[asan] Add support for disable_sanitizer_instrumentation attribute"
This reverts commit 2b554920f1.

This change causes tsan test timeout on x86_64-linux-autoconf.

The timeout can be reproduced by:
  git clone https://github.com/llvm/llvm-zorg.git
  BUILDBOT_CLOBBER= BUILDBOT_REVISION=eef8f3f85679c5b1ae725bade1c23ab7bb6b924f llvm-zorg/zorg/buildbot/builders/sanitizers/buildbot_standard.sh
2021-12-10 14:33:38 -08:00
Alexander Potapenko 2b554920f1 [asan] Add support for disable_sanitizer_instrumentation attribute
For ASan this will effectively serve as a synonym for
__attribute__((no_sanitize("address")))

Differential Revision: https://reviews.llvm.org/D114421
2021-12-10 12:17:26 +01:00
Aaron Ballman 6c75ab5f66 Introduce _BitInt, deprecate _ExtInt
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:

* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.

I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
2021-12-06 12:52:01 -05:00
hsmahesha 3b9a85d10a [CFE][Codegen] Make sure to maintain the contiguity of all the static allocas
at the start of the entry block, which in turn would aid better code transformation/optimization.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D110257
2021-11-10 08:45:21 +05:30
serge-sans-paille 6bfc85c217 Fix inline builtin handling in case of redefinition
Basically, inline builtin definition are shadowed by externally visible
redefinition. This matches GCC behavior.

The implementation has to workaround the fact that:

1. inline builtin are renamed at callsite during codegen, but
2. they may be shadowed by a later external definition

As a consequence, during codegen, we need to walk redecls and eventually rewrite
some call sites, which is totally inelegant.

Differential Revision: https://reviews.llvm.org/D112059
2021-11-02 09:53:49 +01:00
Kazu Hirata dccfaddc6b [clang] Use StringRef::contains (NFC) 2021-10-21 08:58:19 -07:00
hsmahesha 0481682996 [CFE][Codegen][In-progress] Remove CodeGenFunction::InitTempAlloca()
CodeGenFunction::InitTempAlloca() inits the static alloca within the
entry block which may *not* necessarily be correct always.

For example, the current instruction insertion point (pointed by the
instruction builder) could be a program point which is hit multiple
times during the program execution, and it is expected that the static
alloca is initialized every time the program point is hit.

Hence remove CodeGenFunction::InitTempAlloca(), and initialize the
static alloca where the instruction insertion point is at the moment.

This patch, as a starting attempt, removes the calls to
CodeGenFunction::InitTempAlloca() which do not have any side effect on
the lit tests.

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D111293
2021-10-09 09:23:14 +05:30
serge-sans-paille 0f0e31cf51 Update inline builtin handling to honor gnu inline attribute
Per the GCC info page:

    If the function is declared 'extern', then this definition of the
    function is used only for inlining.  In no case is the function
    compiled as a standalone function, not even if you take its address
    explicitly.  Such an address becomes an external reference, as if
    you had only declared the function, and had not defined it.

Respect that behavior for inline builtins: keep the original definition, and
generate a copy of the declaration suffixed by '.inline' that's only referenced
in direct call.

This fixes holes in c3717b6858.

Differential Revision: https://reviews.llvm.org/D111009
2021-10-04 22:26:25 +02:00
serge-sans-paille c3717b6858 Simplify handling of builtin with inline redefinition
(This is a recommit of 3d6f49a569 that should no longer break validation since
bd379915de).

It is a common practice in glibc header to provide an inline redefinition of an
existing function. It is especially the case for fortified function.

Clang currently has an imperfect approach to the problem, using a combination of
trivially recursive function detection and noinline attribute.

Simplify the logic by suffixing these functions by `.inline` during codegen, so
that they are not recognized as builtin by llvm.

After that patch, clang passes all tests from https://github.com/serge-sans-paille/fortify-test-suite

Differential Revision: https://reviews.llvm.org/D109967
2021-09-28 21:00:47 +02:00
Kevin Athey 0d76d4833d Revert "Simplify handling of builtin with inline redefinition"
This reverts commit 3d6f49a569.

Broke bot: https://lab.llvm.org/buildbot/#/builders/5/builds/12360
2021-09-28 11:30:37 -07:00
David Blaikie 85f612efeb DebugInfo: Use sugared function type when emitting function declarations for call sites
Otherwise we're losing type information for these functions.
2021-09-28 10:44:35 -07:00
serge-sans-paille 3d6f49a569 Simplify handling of builtin with inline redefinition
It is a common practice in glibc header to provide an inline redefinition of an
existing function. It is especially the case for fortified function.

Clang currently has an imperfect approach to the problem, using a combination of
trivially recursive function detection and noinline attribute.

Simplify the logic by suffixing these functions by `.inline` during codegen, so
that they are not recognized as builtin by llvm.

After that patch, clang passes all tests from https://github.com/serge-sans-paille/fortify-test-suite

Differential Revision: https://reviews.llvm.org/D109967
2021-09-28 13:24:25 +02:00
Erich Keane 42ae7eb581 Ensure field-annotations on pointers properly match the AS of the field.
Discovered in SYCL, the field annotations were always cast to an i8*,
which is an invalid bitcast for a pointer type with an address space.
This patch makes sure that we create an intrinsic that takes a pointer
to the correct address-space and properly do our casts.

Differential Revision: https://reviews.llvm.org/D109003
2021-09-01 06:12:24 -07:00
Yi Kong 5fc4828aa6 [clang] Don't generate warn-stack-size when the warning is ignored
8ace121305 introduced a regression for code that explicitly ignores the
-Wframe-larger-than= warning. Make sure we don't generate the
warn-stack-size attribute for that case.

Differential Revision: https://reviews.llvm.org/D108686
2021-08-25 14:58:45 +08:00
Alexander Potapenko b0391dfc73 [clang][Codegen] Introduce the disable_sanitizer_instrumentation attribute
The purpose of __attribute__((disable_sanitizer_instrumentation)) is to
prevent all kinds of sanitizer instrumentation applied to a certain
function, Objective-C method, or global variable.

The no_sanitize(...) attribute drops instrumentation checks, but may
still insert code preventing false positive reports. In some cases
though (e.g. when building Linux kernel with -fsanitize=kernel-memory
or -fsanitize=thread) the users may want to avoid any kind of
instrumentation.

Differential Revision: https://reviews.llvm.org/D108029
2021-08-20 14:01:06 +02:00
Dylan Fleming ef198cd99e [SVE] Remove usage of getMaxVScale for AArch64, in favour of IR Attribute
Removed AArch64 usage of the getMaxVScale interface, replacing it with
the vscale_range(min, max) IR Attribute.

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D106277
2021-08-17 14:42:47 +01:00
Melanie Blower bc5b5ea037 [clang][patch][FPEnv] Make initialization of C++ globals strictfp aware
@kpn pointed out that the global variable initialization functions didn't
have the "strictfp" metadata set correctly, and @rjmccall said that there
was buggy code in SetFPModel and StartFunction, this patch is to solve
those problems. When Sema creates a FunctionDecl, it sets the
FunctionDeclBits.UsesFPIntrin to "true" if the lexical FP settings
(i.e. a combination of command line options and #pragma float_control
settings) correspond to ConstrainedFP mode. That bit is used when CodeGen
starts codegen for a llvm function, and it translates into the
"strictfp" function attribute. See bugs.llvm.org/show_bug.cgi?id=44571

Reviewed By: Aaron Ballman

Differential Revision: https://reviews.llvm.org/D102343
2021-07-29 12:02:37 -04:00
Melanie Blower ea864c9933 [clang][patch][NFC] Refactor calculation of FunctionDecl to avoid duplicate code 2021-07-20 11:01:22 -04:00
Nikita Popov 693251fb2f [CodeGen] Avoid CreateGEP with nullptr type (NFC)
In preparation for dropping support for it. I've replaced it with
a proper type where the correct type was obvious and left an
explicit getPointerElementType() where it wasn't.
2021-07-08 20:38:54 +02:00
Bruno De Fraine 4d8871a898 PR50767: clear non-distinct debuginfo for function with nodebug definition after undecorated declaration
Fix suggested by Yuanfang Chen:

Non-distinct debuginfo is attached to the function due to the undecorated declaration. Later, when seeing the function definition and `nodebug` attribute, the non-distinct debuginfo should be cleared.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D104777
2021-06-29 10:26:45 +02:00
Nick Desaulniers 8ace121305 [IR] convert warn-stack-size from module flag to fn attr
Otherwise, this causes issues when building with LTO for object files
that use different values.

Link: https://github.com/ClangBuiltLinux/linux/issues/1395

Reviewed By: dblaikie, MaskRay

Differential Revision: https://reviews.llvm.org/D104342
2021-06-21 15:09:25 -07:00
Nick Desaulniers 193e41c987 [Clang][Codegen] Add GNU function attribute 'no_profile' and lower it to noprofile
noprofile IR attribute already exists to prevent profiling with PGO;
emit that when a function uses the newly added no_profile function
attribute.

The Linux kernel would like to avoid compiler generated code in
functions annotated with such attribute. We already respect this for
libcalls to fentry() and mcount().

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80223
Link: https://lore.kernel.org/lkml/CAKwvOdmPTi93n2L0_yQkrzLdmpxzrOR7zggSzonyaw2PGshApw@mail.gmail.com/

Reviewed By: MaskRay, void, phosek, aaron.ballman

Differential Revision: https://reviews.llvm.org/D104475
2021-06-18 13:42:32 -07:00
Marco Elver 280333021e [SanitizeCoverage] Add support for NoSanitizeCoverage function attribute
We really ought to support no_sanitize("coverage") in line with other
sanitizers. This came up again in discussions on the Linux-kernel
mailing lists, because we currently do workarounds using objtool to
remove coverage instrumentation. Since that support is only on x86, to
continue support coverage instrumentation on other architectures, we
must support selectively disabling coverage instrumentation via function
attributes.

Unfortunately, for SanitizeCoverage, it has not been implemented as a
sanitizer via fsanitize= and associated options in Sanitizers.def, but
rolls its own option fsanitize-coverage. This meant that we never got
"automatic" no_sanitize attribute support.

Implement no_sanitize attribute support by special-casing the string
"coverage" in the NoSanitizeAttr implementation. To keep the feature as
unintrusive to existing IR generation as possible, define a new negative
function attribute NoSanitizeCoverage to propagate the information
through to the instrumentation pass.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=49035

Reviewed By: vitalybuka, morehouse

Differential Revision: https://reviews.llvm.org/D102772
2021-05-25 12:57:14 +02:00
Ten Tzen 797ad70152 [Windows SEH]: HARDWARE EXCEPTION HANDLING (MSVC -EHa) - Part 1
This patch is the Part-1 (FE Clang) implementation of HW Exception handling.

This new feature adds the support of Hardware Exception for Microsoft Windows
SEH (Structured Exception Handling).
This is the first step of this project; only X86_64 target is enabled in this patch.

Compiler options:
For clang-cl.exe, the option is -EHa, the same as MSVC.
For clang.exe, the extra option is -fasync-exceptions,
plus -triple x86_64-windows -fexceptions and -fcxx-exceptions as usual.

NOTE:: Without the -EHa or -fasync-exceptions, this patch is a NO-DIFF change.

The rules for C code:
For C-code, one way (MSVC approach) to achieve SEH -EHa semantic is to follow
three rules:
* First, no exception can move in or out of _try region., i.e., no "potential
  faulty instruction can be moved across _try boundary.
* Second, the order of exceptions for instructions 'directly' under a _try
  must be preserved (not applied to those in callees).
* Finally, global states (local/global/heap variables) that can be read
  outside of _try region must be updated in memory (not just in register)
  before the subsequent exception occurs.

The impact to C++ code:
Although SEH is a feature for C code, -EHa does have a profound effect on C++
side. When a C++ function (in the same compilation unit with option -EHa ) is
called by a SEH C function, a hardware exception occurs in C++ code can also
be handled properly by an upstream SEH _try-handler or a C++ catch(...).
As such, when that happens in the middle of an object's life scope, the dtor
must be invoked the same way as C++ Synchronous Exception during unwinding
process.

Design:
A natural way to achieve the rules above in LLVM today is to allow an EH edge
added on memory/computation instruction (previous iload/istore idea) so that
exception path is modeled in Flow graph preciously. However, tracking every
single memory instruction and potential faulty instruction can create many
Invokes, complicate flow graph and possibly result in negative performance
impact for downstream optimization and code generation. Making all
optimizations be aware of the new semantic is also substantial.

This design does not intend to model exception path at instruction level.
Instead, the proposed design tracks and reports EH state at BLOCK-level to
reduce the complexity of flow graph and minimize the performance-impact on CPP
code under -EHa option.

One key element of this design is the ability to compute State number at
block-level. Our algorithm is based on the following rationales:

A _try scope is always a SEME (Single Entry Multiple Exits) region as jumping
into a _try is not allowed. The single entry must start with a seh_try_begin()
invoke with a correct State number that is the initial state of the SEME.
Through control-flow, state number is propagated into all blocks. Side exits
marked by seh_try_end() will unwind to parent state based on existing
SEHUnwindMap[].
Note side exits can ONLY jump into parent scopes (lower state number).
Thus, when a block succeeds various states from its predecessors, the lowest
State triumphs others.  If some exits flow to unreachable, propagation on those
paths terminate, not affecting remaining blocks.
For CPP code, object lifetime region is usually a SEME as SEH _try.
However there is one rare exception: jumping into a lifetime that has Dtor but
has no Ctor is warned, but allowed:

Warning: jump bypasses variable with a non-trivial destructor

In that case, the region is actually a MEME (multiple entry multiple exits).
Our solution is to inject a eha_scope_begin() invoke in the side entry block to
ensure a correct State.

Implementation:
Part-1: Clang implementation described below.

Two intrinsic are created to track CPP object scopes; eha_scope_begin() and eha_scope_end().
_scope_begin() is immediately added after ctor() is called and EHStack is pushed.
So it must be an invoke, not a call. With that it's also guaranteed an
EH-cleanup-pad is created regardless whether there exists a call in this scope.
_scope_end is added before dtor(). These two intrinsics make the computation of
Block-State possible in downstream code gen pass, even in the presence of
ctor/dtor inlining.

Two intrinsic, seh_try_begin() and seh_try_end(), are added for C-code to mark
_try boundary and to prevent from exceptions being moved across _try boundary.
All memory instructions inside a _try are considered as 'volatile' to assure
2nd and 3rd rules for C-code above. This is a little sub-optimized. But it's
acceptable as the amount of code directly under _try is very small.

Part-2 (will be in Part-2 patch): LLVM implementation described below.

For both C++ & C-code, the state of each block is computed at the same place in
BE (WinEHPreparing pass) where all other EH tables/maps are calculated.
In addition to _scope_begin & _scope_end, the computation of block state also
rely on the existing State tracking code (UnwindMap and InvokeStateMap).

For both C++ & C-code, the state of each block with potential trap instruction
is marked and reported in DAG Instruction Selection pass, the same place where
the state for -EHsc (synchronous exceptions) is done.
If the first instruction in a reported block scope can trap, a Nop is injected
before this instruction. This nop is needed to accommodate LLVM Windows EH
implementation, in which the address in IPToState table is offset by +1.
(note the purpose of that is to ensure the return address of a call is in the
same scope as the call address.

The handler for catch(...) for -EHa must handle HW exception. So it is
'adjective' flag is reset (it cannot be IsStdDotDot (0x40) that only catches
C++ exceptions).
Suppress push/popTerminate() scope (from noexcept/noTHrow) so that HW
exceptions can be passed through.

Original llvm-dev [RFC] discussions can be found in these two threads below:
https://lists.llvm.org/pipermail/llvm-dev/2020-March/140541.html
https://lists.llvm.org/pipermail/llvm-dev/2020-April/141338.html

Differential Revision: https://reviews.llvm.org/D80344/new/
2021-05-17 22:42:17 -07:00
Florian Hahn 6c31295493
[clang] Refactor mustprogress handling, add it to all loops in c++11+.
Currently Clang does not add mustprogress to inifinite loops with a
known constant condition, matching C11 behavior. The forward progress
guarantee in C++11 and later should allow us to add mustprogress to any
loop (http://eel.is/c++draft/intro.progress#1).

This allows us to simplify the code dealing with adding mustprogress a
bit.

Reviewed By: aaron.ballman, lebedev.ri

Differential Revision: https://reviews.llvm.org/D96418
2021-04-30 14:13:47 +01:00
Serge Guelton d6de1e1a71 Normalize interaction with boolean attributes
Such attributes can either be unset, or set to "true" or "false" (as string).
throughout the codebase, this led to inelegant checks ranging from

        if (Fn->getFnAttribute("no-jump-tables").getValueAsString() == "true")

to

        if (Fn->hasAttribute("no-jump-tables") && Fn->getFnAttribute("no-jump-tables").getValueAsString() == "true")

Introduce a getValueAsBool that normalize the check, with the following
behavior:

no attributes or attribute set to "false" => return false
attribute set to "true" => return true

Differential Revision: https://reviews.llvm.org/D99299
2021-04-17 08:17:33 +02:00
yifeng.dongyifeng 3a6a80b641 [Clang][Coroutine][DebugInfo] In c++ coroutine, clang will emit different debug info variables for parameters and move-parameters.
The first one is the real parameters of the coroutine function, the
other one just for copying parameters to the coroutine frame.

Considering the following c++ code:
```
struct coro {
  ...
};

coro foo(struct test & t) {
  ...
  co_await suspend_always();
    ...
    co_await suspend_always();
    ...
    co_await suspend_always();
}

int main(int argc, char *argv[]) {
  auto c = foo(...);
    c.handle.resume();
      ...
  }
```

Function foo is the standard coroutine function, and it has only
one parameter named t (ignoring this at first),
when we use the llvm code to compile this function, we can get the
following ir:

```
!2921 = distinct !DISubprogram(name: "foo", linkageName:
"_ZN6Object3fooE4test", scope: !2211, file: !45, li\
ne: 48, type: !2329, scopeLine: 48, flags: DIFlagPrototyped |
DIFlagAllCallsDescribed, spFlags: DISPFlagDefi\
nition | DISPFlagOptimized, unit: !44, declaration: !2328,
retainedNodes: !2922)
!2924 = !DILocalVariable(name: "t", arg: 2, scope: !2921, file: !45,
line: 48, type: !838)
...
!2926 = !DILocalVariable(name: "t", scope: !2921, type: !838, flags:
DIFlagArtificial)
```
We can find there are two `the same` DIVariable named t in the same
dwarf scope for foo.resume.
And when we try to use llvm-dwarfdump to dump the dwarf info of this
elf, we get the following output:

```
0x00006684:   DW_TAG_subprogram
                DW_AT_low_pc    (0x00000000004013a0)
                DW_AT_high_pc   (0x00000000004013a8)
                DW_AT_frame_base        (DW_OP_reg7 RSP)
                DW_AT_object_pointer    (0x0000669c)
                DW_AT_GNU_all_call_sites        (true)
                DW_AT_specification     (0x00005b5c "_ZN6Object3fooE4test")

0x000066a5:     DW_TAG_formal_parameter
                DW_AT_name    ("t")
                DW_AT_decl_file       ("/disk1/yifeng.dongyifeng/my_code/llvm/build/bin/coro-debug-1.cpp")
                DW_AT_decl_line       (48)
                DW_AT_type    (0x00004146 "test")

0x000066ba:     DW_TAG_variable
                  DW_AT_name    ("t")
                  DW_AT_type    (0x00004146 "test")
                  DW_AT_artificial      (true)
```
The elf also has two 't' in the same scope.
But unluckily, it might let the debugger
confused. And failed to print parameters for O0 or above.
This patch will make coroutine parameters and move
parameters use the same DIVar and try to fix the problems
that I mentioned before.

Test Plan: check-clang

Reviewed By: aprantl, jmorse

Differential Revision: https://reviews.llvm.org/D97533
2021-04-12 11:10:47 +08:00
Dávid Bolvanský 2cb8c10342 Revert "Reduce the number of attributes attached to each function"
This reverts commit 053dc95839. It causes perf regressions - see discussion in D97116.
2021-04-08 17:28:57 +02:00
Xun Li c7a39c833a [Coroutine][Clang] Force emit lifetime intrinsics for Coroutines
tl;dr Correct implementation of Corouintes requires having lifetime intrinsics available.

Coroutine functions are functions that can be suspended and resumed latter. To do so, data that need to stay alive after suspension must be put on the heap (i.e. the coroutine frame).
The optimizer is responsible for analyzing each AllocaInst and figure out whether it should be put on the stack or the frame.
In most cases, for data that we are unable to accurately analyze lifetime, we can just conservatively put them on the heap.
Unfortunately, there exists a few cases where certain data MUST be put on the stack, not on the heap. Without lifetime intrinsics, we are unable to correctly analyze those data's lifetime.

To dig into more details, there exists cases where at certain code points, the current coroutine frame may have already been destroyed. Hence no frame access would be allowed beyond that point.
The following is a common code pattern called "Symmetric Transfer" in coroutine:
```
auto tmp = await_suspend();
__builtin_coro_resume(tmp.address());
return;
```
In the above code example, `await_suspend()` returns a new coroutine handle, which we will obtain the address and then resume that coroutine. This essentially "transfered" from the current coroutine to a different coroutine.
During the call to `await_suspend()`, the current coroutine may be destroyed, which should be fine because we are not accessing any data afterwards.
However when LLVM is emitting IR for the above code, it needs to emit an AllocaInst for `tmp`. It will then call the `address` function on tmp. `address` function is a member function of coroutine, and there is no way for the LLVM optimizer to know that it does not capture the `tmp` pointer. So when the optimizer looks at it, it has to conservatively assume that `tmp` may escape and hence put it on the heap. Furthermore, in some cases `address` call would be inlined, which will generate a bunch of store/load instructions that move the `tmp` pointer around. Those stores will also make the compiler to think that `tmp` might escape.
To summarize, it's really difficult for the mid-end to figure out that the `tmp` data is short-lived.
I made some attempt in D98638, but it appears to be way too complex and is basically doing the same thing as inserting lifetime intrinsics in coroutines.

Also, for reference, we already force emitting lifetime intrinsics in O0 for AlwaysInliner: https://github.com/llvm/llvm-project/blob/main/llvm/lib/Passes/PassBuilder.cpp#L1893

Differential Revision: https://reviews.llvm.org/D99227
2021-03-25 13:46:20 -07:00
Bradley Smith 48f5a392cb [IR] Add vscale_range IR function attribute
This attribute represents the minimum and maximum values vscale can
take. For now this attribute is not hooked up to anything during
codegen, this will be added in the future when such codegen is
considered stable.

Additionally hook up the -msve-vector-bits=<x> clang option to emit this
attribute.

Differential Revision: https://reviews.llvm.org/D98030
2021-03-22 12:05:06 +00:00
Roman Lebedev be87321280
[clang][Codegen] EmitBranchOnBoolExpr(): emit prof branch counts even at -O0
This restores the original behaviour before i unadvertedly broke it in
e3a4701627 and clang/test/Profile/ caught it.
2021-03-21 23:24:27 +03:00
Roman Lebedev e3a4701627
[clang][CodeGen] Lower Likelihood attributes to @llvm.expect intrin instead of branch weights
08196e0b2e exposed LowerExpectIntrinsic's
internal implementation detail in the form of
LikelyBranchWeight/UnlikelyBranchWeight options to the outside.

While this isn't incorrect from the results viewpoint,
this is suboptimal from the layering viewpoint,
and causes confusion - should transforms also use those weights,
or should they use something else, D98898?

So go back to status quo by making LikelyBranchWeight/UnlikelyBranchWeight
internal again, and fixing all the code that used it directly,
which currently is only clang codegen, thankfully,
to emit proper @llvm.expect intrinsics instead.
2021-03-21 22:50:21 +03:00
Roman Lebedev 37d6be9052
Revert "[BranchProbability] move options for 'likely' and 'unlikely'"
Upon reviewing D98898 i've come to realization that these are
implementation detail of LowerExpectIntrinsicPass,
and they should not be exposed to outside of it.

This reverts commit ee8b53815d.
2021-03-21 22:50:21 +03:00
Sanjay Patel ee8b53815d [BranchProbability] move options for 'likely' and 'unlikely'
This makes the settings available for use in other passes by housing
them within the Support lib, but NFC otherwise.

See D98898 for the proposed usage in SimplifyCFG
(where this change was originally included).

Differential Revision: https://reviews.llvm.org/D98945
2021-03-20 14:46:46 -04:00
Nikita Popov 42eb658f65 [OpaquePtrs] Remove some uses of type-less CreateGEP() (NFC)
This removes some (but not all) uses of type-less CreateGEP()
and CreateInBoundsGEP() APIs, which are incompatible with opaque
pointers.

There are a still a number of tricky uses left, as well as many
more variation APIs for CreateGEP.
2021-03-12 21:01:16 +01:00
Nikita Popov 68e01339cc [CGBuilder] Remove type-less CreateAlignedLoad() APIs (NFC)
These are incompatible with opaque pointers. This is in preparation
of dropping this API on the IRBuilder side as well.

Instead explicitly pass the loaded type.
2021-03-11 10:41:23 +01:00
Michael Kruse b119120673 [clang][OpenMP] Use OpenMPIRBuilder for workshare loops.
Initial support for using the OpenMPIRBuilder by clang to generate loops using the OpenMPIRBuilder. This initial support is intentionally limited to:
 * Only the worksharing-loop directive.
 * Recognizes only the nowait clause.
 * No loop nests with more than one loop.
 * Untested with templates, exceptions.
 * Semantic checking left to the existing infrastructure.

This patch introduces a new AST node, OMPCanonicalLoop, which becomes parent of any loop that has to adheres to the restrictions as specified by the OpenMP standard. These restrictions allow OMPCanonicalLoop to provide the following additional information that depends on base language semantics:
 * The distance function: How many loop iterations there will be before entering the loop nest.
 * The loop variable function: Conversion from a logical iteration number to the loop variable.

These allow the OpenMPIRBuilder to act solely using logical iteration numbers without needing to be concerned with iterator semantics between calling the distance function and determining what the value of the loop variable ought to be. Any OpenMP logical should be done by the OpenMPIRBuilder such that it can be reused MLIR OpenMP dialect and thus by flang.

The distance and loop variable function are implemented using lambdas (or more exactly: CapturedStmt because lambda implementation is more interviewed with the parser). It is up to the OpenMPIRBuilder how they are called which depends on what is done with the loop. By default, these are emitted as outlined functions but we might think about emitting them inline as the OpenMPRuntime does.

For compatibility with the current OpenMP implementation, even though not necessary for the OpenMPIRBuilder, OMPCanonicalLoop can still be nested within OMPLoopDirectives' CapturedStmt. Although OMPCanonicalLoop's are not currently generated when the OpenMPIRBuilder is not enabled, these can just be skipped when not using the OpenMPIRBuilder in case we don't want to make the AST dependent on the EnableOMPBuilder setting.

Loop nests with more than one loop require support by the OpenMPIRBuilder (D93268). A simple implementation of non-rectangular loop nests would add another lambda function that returns whether a loop iteration of the rectangular overapproximation is also within its non-rectangular subset.

Reviewed By: jdenny

Differential Revision: https://reviews.llvm.org/D94973
2021-03-04 22:52:59 -06:00
Reid Kleckner 1c2e7d200d [MS] Fix crash involving gnu stmt exprs and inalloca
Use a WeakTrackingVH to cope with the stmt emission logic that cleans up
unreachable blocks. This invalidates the reference to the deferred
replacement placeholder. Cope with it.

Fixes PR25102 (from 2015!)
2021-03-04 13:57:46 -08:00
Gui Andrade 10264a1b21 Introduce noundef attribute at call sites for stricter poison analysis
This change adds a new IR noundef attribute, which denotes when a function call argument or return val may never contain uninitialized bits.

In MemorySanitizer, this attribute enables optimizations which decrease instrumented code size by up to 17% (measured with an instrumented build of clang) . I'll introduce the change allowing msan to take advantage of this information in a separate patch.

Differential Revision: https://reviews.llvm.org/D81678
2021-03-04 12:15:12 -08:00
Dávid Bolvanský 053dc95839 Reduce the number of attributes attached to each function
Patch takes advantage of the implicit default behavior to reduce the number of attributes, which in turns reduces compilation time.

Reviewed By: serge-sans-paille

Differential Revision: https://reviews.llvm.org/D97116
2021-02-24 07:08:44 +01:00
Melanie Blower e64fcdf8d5 [clang][patch] Inclusive language, modify filename SanitizerBlacklist.h to NoSanitizeList.h
This patch responds to a comment from @vitalybuka in D96203: suggestion to
do the change incrementally, and start by modifying this file name. I modified
the file name and made the other changes that follow from that rename.

Reviewers: vitalybuka, echristo, MaskRay, jansvoboda11, aaron.ballman

Differential Revision: https://reviews.llvm.org/D96974
2021-02-22 15:11:37 -05:00
Dávid Bolvanský ee51c42e00 Reduce the number of attributes attached to each function
This takes advantage of the implicit default behavior to reduce the number of
attributes.
2021-02-20 06:57:47 +01:00
Petr Hosek bb9eb19829 Support for instrumenting only selected files or functions
This change implements support for applying profile instrumentation
only to selected files or functions. The implementation uses the
sanitizer special case list format to select which files and functions
to instrument, and relies on the new noprofile IR attribute to exclude
functions from instrumentation.

Differential Revision: https://reviews.llvm.org/D94820
2021-01-26 17:13:34 -08:00
Petr Hosek 1e634f3952 Revert "Support for instrumenting only selected files or functions"
This reverts commit 4edf35f11a because
the test fails on Windows bots.
2021-01-26 12:25:28 -08:00
Petr Hosek 4edf35f11a Support for instrumenting only selected files or functions
This change implements support for applying profile instrumentation
only to selected files or functions. The implementation uses the
sanitizer special case list format to select which files and functions
to instrument, and relies on the new noprofile IR attribute to exclude
functions from instrumentation.

Differential Revision: https://reviews.llvm.org/D94820
2021-01-26 11:11:39 -08:00
Fangrui Song b88c8f1aab CGDebugInfo: Delete unused parameters 2021-01-11 13:39:03 -08:00
Alan Phipps 9f2967bcfe [Coverage] Add support for Branch Coverage in LLVM Source-Based Code Coverage
This is an enhancement to LLVM Source-Based Code Coverage in clang to track how
many times individual branch-generating conditions are taken (evaluate to TRUE)
and not taken (evaluate to FALSE).  Individual conditions may comprise larger
boolean expressions using boolean logical operators.  This functionality is
very similar to what is supported by GCOV except that it is very closely
anchored to the ASTs.

Differential Revision: https://reviews.llvm.org/D84467
2021-01-05 09:51:51 -06:00
James Y Knight 4ddf140c00 Fix PR35902: incorrect alignment used for ubsan check.
UBSan was using the complete-object align rather than nv alignment
when checking the "this" pointer of a method.

Furthermore, CGF.CXXABIThisAlignment was also being set incorrectly,
due to an incorrectly negated test. The latter doesn't appear to have
had any impact, due to it not really being used anywhere.

Differential Revision: https://reviews.llvm.org/D93072
2020-12-28 18:11:17 -05:00
Kevin P. Neal 2069403cdf [FPEnv] Use strictfp metadata in casting nodes
The strictfp metadata was added to the casting AST nodes in D85960, but
we aren't using that metadata yet. This patch adds that support.

In order to avoid lots of ad-hoc passing around of the strictfp bits I
updated the IRBuilder when moving from a function that has the Expr* to a
function that lacks it. I believe we should switch to this pattern to keep
the strictfp support from being overly invasive.

For the purpose of testing that we're picking up the right metadata, I
also made my tests use a pragma to make the AST's strictfp metadata not
match the global strictfp metadata. This exposes issues that we need to
deal with in subsequent patches, and I believe this is the right method
for most all of our clang strictfp tests.

Differential Revision: https://reviews.llvm.org/D88913
2020-11-06 11:56:12 -05:00
Atmn Patel ac73b73c16 [clang] Add mustprogress and llvm.loop.mustprogress attribute deduction
Since C++11, the C++ standard has a forward progress guarantee
[intro.progress], so all such functions must have the `mustprogress`
requirement. In addition, from C11 and onwards, loops without a non-zero
constant conditional or no conditional are also required to make
progress (C11 6.8.5p6). This patch implements these attribute deductions
so they can be used by the optimization passes.

Differential Revision: https://reviews.llvm.org/D86841
2020-11-04 22:03:14 -05:00
Mark de Wever b46fddf75f [CodeGen] Implement [[likely]] and [[unlikely]] for while and for loop.
The attribute has no effect on a do statement since the path of execution
will always include its substatement.

It adds a diagnostic when the attribute is used on an infinite while loop
since the codegen omits the branch here. Since the likelihood attributes
have no effect on a do statement no diagnostic will be issued for
do [[unlikely]] {...} while(0);

Differential Revision: https://reviews.llvm.org/D89899
2020-10-31 17:51:29 +01:00
Liu, Chen3 00090a2b82 Support complex target features combinations
This patch is mainly doing two things:

1. Adding support for parentheses, making the combination of target features
   more diverse;
2. Making the priority of ’,‘ is higher than that of '|' by default. So I need
   to make some change with PTX Builtin function.

Differential Revision: https://reviews.llvm.org/D89184
2020-10-30 10:32:53 +08:00
Tyker d3205bbca3 [Annotation] Allows annotation to carry some additional constant arguments.
This allows using annotation in a much more contexts than it currently has.
especially when annotation with template or constexpr.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D88645
2020-10-26 10:50:05 +01:00
Melanie Blower 2e204e2391 [clang] Enable support for #pragma STDC FENV_ACCESS
Reviewers: rjmccall, rsmith, sepavloff

Differential Revision: https://reviews.llvm.org/D87528
2020-10-25 06:46:25 -07:00
Mark de Wever 2bcda6bb28 [Sema, CodeGen] Implement [[likely]] and [[unlikely]] in SwitchStmt
This implements the likelihood attribute for the switch statement. Based on the
discussion in D85091 and D86559 it only handles the attribute when placed on
the case labels or the default labels.

It also marks the likelihood attribute as feature complete. There are more QoI
patches in the pipeline.

Differential Revision: https://reviews.llvm.org/D89210
2020-10-18 13:48:42 +02:00
Mark de Wever 1113fbf44c [CodeGen] Improve likelihood branch weights
Bruno De Fraine discovered some issues with D85091. The branch weights
generated for `logical not` and `ternary conditional` were wrong. The
`logical and` and `logical or` differed from the code generated of
`__builtin_predict`.

Adjusted the generated code for the likelihood to match
`__builtin_predict`. The patch is based on Bruno's suggestions.

Differential Revision: https://reviews.llvm.org/D88363
2020-10-04 14:24:27 +02:00
Ian Levesque 6f7fbdd285 [xray] Function coverage groups
Add the ability to selectively instrument a subset of functions by dividing the functions into N logical groups and then selecting a group to cover. By selecting different groups over time you could cover the entire application incrementally with lower overhead than instrumenting the entire application at once.

Differential Revision: https://reviews.llvm.org/D87953
2020-09-24 22:09:53 -04:00
Tyker 78de7297ab Reland [AssumeBundles] Use operand bundles to encode alignment assumptions
NOTE: There is a mailing list discussion on this: http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

Complemantary to the assumption outliner prototype in D71692, this patch
shows how we could simplify the code emitted for an alignemnt
assumption. The generated code is smaller, less fragile, and it makes it
easier to recognize the additional use as a "assumption use".

As mentioned in D71692 and on the mailing list, we could adopt this
scheme, and similar schemes for other patterns, without adopting the
assumption outlining.
2020-09-12 15:36:06 +02:00
Mark de Wever 08196e0b2e Implements [[likely]] and [[unlikely]] in IfStmt.
This is the initial part of the implementation of the C++20 likelihood
attributes. It handles the attributes in an if statement.

Differential Revision: https://reviews.llvm.org/D85091
2020-09-09 20:48:37 +02:00
Richard Smith 740a164dec PR46377: Fix dependence calculation for function types and typedef
types.

We previously did not treat a function type as dependent if it had a
parameter pack with a non-dependent type -- such a function type depends
on the arity of the pack so is dependent even though none of the
parameter types is dependent. In order to properly handle this, we now
treat pack expansion types as always being dependent types (depending on
at least the pack arity), and always canonically being pack expansion
types, even in the unusual case when the pattern is not a dependent
type. This does mean that we can have canonical types that are pack
expansions that contain no unexpanded packs, which is unfortunate but
not inaccurate.

We also previously did not treat a typedef type as
instantiation-dependent if its canonical type was not
instantiation-dependent. That's wrong because instantiation-dependence
is a property of the type sugar, not of the type; an
instantiation-dependent type can have a non-instantiation-dependent
canonical type.
2020-07-28 13:23:13 -07:00
Eric Christopher 7bfaa40086 Temporarily Revert "[AssumeBundles] Use operand bundles to encode alignment assumptions"
due to the performance bugs filed in https://bugs.llvm.org/show_bug.cgi?id=46753.

An SROA change soon may obviate some of these problems.

This reverts commit 8d09f20798.
2020-07-16 11:54:04 -07:00
Tyker 8d09f20798 [AssumeBundles] Use operand bundles to encode alignment assumptions
Summary:
NOTE: There is a mailing list discussion on this: http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

Complemantary to the assumption outliner prototype in D71692, this patch
shows how we could simplify the code emitted for an alignemnt
assumption. The generated code is smaller, less fragile, and it makes it
easier to recognize the additional use as a "assumption use".

As mentioned in D71692 and on the mailing list, we could adopt this
scheme, and similar schemes for other patterns, without adopting the
assumption outlining.

Reviewers: hfinkel, xbolva00, lebedev.ri, nikic, rjmccall, spatel, jdoerfert, sstefan1

Reviewed By: jdoerfert

Subscribers: thopre, yamauchi, kuter, fhahn, merge_guards_bot, hiraditya, bollu, rkruppe, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D71739
2020-07-14 01:05:58 +02:00
sstefan1 6aab27ba85 [OpenMPIRBuilder][Fix] Move llvm::omp::types to OpenMPIRBuilder.
Summary:
D82193 exposed a problem with global type definitions in
`OMPConstants.h`. This causes a race when running in thinLTO mode.
Types now live inside of OpenMPIRBuilder to prevent this from happening.

Reviewers: jdoerfert

Subscribers: yaxunl, hiraditya, guansong, dexonsmith, aaron.ballman, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D83176
2020-07-08 17:23:55 +02:00
Roman Lebedev 7ea46aee36
Revert "[AssumeBundles] Use operand bundles to encode alignment assumptions"
Assume bundle can have more than one entry with the same name,
but at least AlignmentFromAssumptionsPass::extractAlignmentInfo() uses
getOperandBundle("align"), which internally assumes that it isn't the
case, and happily crashes otherwise.

Minimal reduced reproducer: run `opt -alignment-from-assumptions` on

target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

%0 = type { i64, %1*, i8*, i64, %2, i32, %3*, i8* }
%1 = type opaque
%2 = type { i8, i8, i16 }
%3 = type { i32, i32, i32, i32 }

; Function Attrs: nounwind
define i32 @f(%0* noalias nocapture readonly %arg, %0* noalias %arg1) local_unnamed_addr #0 {
bb:
  call void @llvm.assume(i1 true) [ "align"(%0* %arg, i64 8), "align"(%0* %arg1, i64 8) ]
  ret i32 0
}

; Function Attrs: nounwind willreturn
declare void @llvm.assume(i1) #1

attributes #0 = { nounwind "reciprocal-estimates"="none" }
attributes #1 = { nounwind willreturn }


This is what we'd have with -mllvm -enable-knowledge-retention

This reverts commit c95ffadb24.
2020-07-04 23:49:23 +03:00
Melanie Blower f4aaed3bf1 Reland D81869 "Modify FPFeatures to use delta not absolute settings"
This reverts commit defd43a5b3.
with correction to solve msan report

To solve https://bugs.llvm.org/show_bug.cgi?id=46166 where the
floating point settings in PCH files aren't compatible, rewrite
FPFeatures to use a delta in the settings rather than absolute settings.
With this patch, these floating point options can be benign.

Reviewers: rjmccall

Differential Revision: https://reviews.llvm.org/D81869
2020-06-27 01:34:57 -07:00
Melanie Blower defd43a5b3 Revert "Revert "Revert "Modify FPFeatures to use delta not absolute settings"""
This reverts commit 9518763d71.
Memory sanitizer fails in CGFPOptionsRAII::CGFPOptionsRAII dtor
2020-06-26 08:47:04 -07:00
Melanie Blower 9518763d71 Revert "Revert "Modify FPFeatures to use delta not absolute settings""
This reverts commit b55d723ed6.
Reapply Modify FPFeatures to use delta not absolute settings

To solve https://bugs.llvm.org/show_bug.cgi?id=46166 where the
floating point settings in PCH files aren't compatible, rewrite
FPFeatures to use a delta in the settings rather than absolute settings.
With this patch, these floating point options can be benign.

Reviewers: rjmccall

Differential Revision: https://reviews.llvm.org/D81869
2020-06-26 08:00:08 -07:00
Melanie Blower b55d723ed6 Revert "Modify FPFeatures to use delta not absolute settings"
This reverts commit 3a748cbf86.
I'm reverting this commit because I forgot to format the commit message
propertly. Sorry for the thrash.
2020-06-26 07:52:57 -07:00
Melanie Blower 3a748cbf86 Modify FPFeatures to use delta not absolute settings 2020-06-26 07:41:09 -07:00
Tyker c95ffadb24 [AssumeBundles] Use operand bundles to encode alignment assumptions
Summary:
NOTE: There is a mailing list discussion on this: http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

Complemantary to the assumption outliner prototype in D71692, this patch
shows how we could simplify the code emitted for an alignemnt
assumption. The generated code is smaller, less fragile, and it makes it
easier to recognize the additional use as a "assumption use".

As mentioned in D71692 and on the mailing list, we could adopt this
scheme, and similar schemes for other patterns, without adopting the
assumption outlining.

Reviewers: hfinkel, xbolva00, lebedev.ri, nikic, rjmccall, spatel, jdoerfert, sstefan1

Reviewed By: jdoerfert

Subscribers: yamauchi, kuter, fhahn, merge_guards_bot, hiraditya, bollu, rkruppe, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D71739
2020-06-25 12:59:44 +02:00
Akira Hatanaka c9a52de002 [CodeGen] Simplify the way lifetime of block captures is extended
Rather than pushing inactive cleanups for the block captures at the
entry of a full expression and activating them during the creation of
the block literal, just call pushLifetimeExtendedDestroy to ensure the
cleanups are popped at the end of the scope enclosing the block
expression.

rdar://problem/63996471

Differential Revision: https://reviews.llvm.org/D81624
2020-06-11 16:06:22 -07:00
John McCall 7fac1acc61 Set the LLVM FP optimization flags conservatively.
Functions can have local pragmas that override the global settings.
We set the flags eagerly based on global settings, but if we emit
an expression under the influence of a pragma, we clear the
appropriate flags from the function.

In order to avoid doing a ton of redundant work whenever we emit
an FP expression, configure the IRBuilder to default to global
settings, and only reconfigure it when we see an FP expression
that's not using the global settings.

Patch by Michele Scandale!

https://reviews.llvm.org/D80462
2020-06-11 18:16:41 -04:00
Wei Mi 7a6c89427c [SampleFDO] Add use-sample-profile function attribute.
When sampleFDO is enabled, people may expect they can use
-fno-profile-sample-use to opt-out using sample profile for a certain file.
That could be either for debugging purpose or for performance tuning purpose.
However, when thinlto is enabled, if a function in file A compiled with
-fno-profile-sample-use is imported to another file B compiled with
-fprofile-sample-use, the inlined copy of the function in file B may still
get its profile annotated.

The inconsistency may even introduce profile unused warning because if the
target is not compiled with explicit debug information flag, the function
in file A won't have its debug information enabled (debug information will
be enabled implicitly only when -fprofile-sample-use is used). After it is
imported into file B which is compiled with -fprofile-sample-use, profile
annotation for the outline copy of the function will fail because the
function has no debug information, and that will trigger  profile unused
warning.

We add a new attribute use-sample-profile to control whether a function
will use its sample profile no matter for its outline or inline copies.
That will make the behavior of -fno-profile-sample-use consistent.

Differential Revision: https://reviews.llvm.org/D79959
2020-06-02 17:23:17 -07:00
John McCall 8a8d703be0 Fix how cc1 command line options are mapped into FP options.
Canonicalize on storing FP options in LangOptions instead of
redundantly in CodeGenOptions.  Incorporate -ffast-math directly
into the values of those LangOptions rather than considering it
separately when building FPOptions.  Build IR attributes from
those options rather than a mix of sources.

We should really simplify the driver/cc1 interaction here and have
the driver pass down options that cc1 directly honors.  That can
happen in a follow-up, though.

Patch by Michele Scandale!
https://reviews.llvm.org/D80315
2020-06-01 22:00:30 -04:00
Eli Friedman 62f3ef2b53 [CGCall] Annotate references with "align" attribute.
If we're going to assume references are dereferenceable, we should also
assume they're aligned: otherwise, we can't actually dereference them.

See also D80072.

Differential Revision: https://reviews.llvm.org/D80166
2020-05-19 20:21:30 -07:00
Florian Hahn 1065869195 [Matrix] Add matrix type to Clang.
This patch adds a matrix type to Clang as described in the draft
specification in clang/docs/MatrixSupport.rst. It introduces a new option
-fenable-matrix, which can be used to enable the matrix support.

The patch adds new MatrixType and DependentSizedMatrixType types along
with the plumbing required. Loads of and stores to pointers to matrix
values are lowered to memory operations on 1-D IR arrays. After loading,
the loaded values are cast to a vector. This ensures matrix values use
the alignment of the element type, instead of LLVM's large vector
alignment.

The operators and builtins described in the draft spec will will be added in
follow-up patches.

Reviewers: martong, rsmith, Bigcheese, anemet, dexonsmith, rjmccall, aaron.ballman

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D72281
2020-05-11 18:55:45 +01:00
Melanie Blower f5360d4bb3 Reapply "Add support for #pragma float_control" with buildbot fixes
Add support for #pragma float_control

Reviewers: rjmccall, erichkeane, sepavloff

Differential Revision: https://reviews.llvm.org/D72841

This reverts commit fce82c0ed3.
2020-05-04 05:51:25 -07:00
Melanie Blower fce82c0ed3 Revert "Reapply "Add support for #pragma float_control" with improvements to"
This reverts commit 69aacaf699.
2020-05-01 10:31:09 -07:00
Melanie Blower 69aacaf699 Reapply "Add support for #pragma float_control" with improvements to
test cases
Add support for #pragma float_control

Reviewers: rjmccall, erichkeane, sepavloff

Differential Revision: https://reviews.llvm.org/D72841

This reverts commit 85dc033cac, and makes
corrections to the test cases that failed on buildbots.
2020-05-01 10:03:30 -07:00
Melanie Blower 85dc033cac Revert "Add support for #pragma float_control"
This reverts commit 4f1e9a17e9.
due to fail on buildbot, sorry for the noise
2020-05-01 06:36:58 -07:00
Melanie Blower 4f1e9a17e9 Add support for #pragma float_control
Reviewers: rjmccall, erichkeane, sepavloff

Differential Revision: https://reviews.llvm.org/D72841
2020-05-01 06:14:24 -07:00
Craig Topper a58b62b4a2 [IR] Replace all uses of CallBase::getCalledValue() with getCalledOperand().
This method has been commented as deprecated for a while. Remove
it and replace all uses with the equivalent getCalledOperand().

I also made a few cleanups in here. For example, to removes use
of getElementType on a pointer when we could just use getFunctionType
from the call.

Differential Revision: https://reviews.llvm.org/D78882
2020-04-27 22:17:03 -07:00
Erich Keane 5f0903e9be Reland Implement _ExtInt as an extended int type specifier.
I fixed the LLDB issue, so re-applying the patch.

This reverts commit a4b88c0449.
2020-04-17 10:45:48 -07:00
Sterling Augustine a4b88c0449 Revert "Implement _ExtInt as an extended int type specifier."
This reverts commit 61ba1481e2.

I'm reverting this because it breaks the lldb build with
incomplete switch coverage warnings. I would fix it forward,
but am not familiar enough with lldb to determine the correct
fix.

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:3958:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
          ^
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4633:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
          ^
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4889:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
2020-04-17 10:29:40 -07:00
Erich Keane 61ba1481e2 Implement _ExtInt as an extended int type specifier.
Introduction/Motivation:
LLVM-IR supports integers of non-power-of-2 bitwidth, in the iN syntax.
Integers of non-power-of-two aren't particularly interesting or useful
on most hardware, so much so that no language in Clang has been
motivated to expose it before.

However, in the case of FPGA hardware normal integer types where the
full bitwidth isn't used, is extremely wasteful and has severe
performance/space concerns.  Because of this, Intel has introduced this
functionality in the High Level Synthesis compiler[0]
under the name "Arbitrary Precision Integer" (ap_int for short). This
has been extremely useful and effective for our users, permitting them
to optimize their storage and operation space on an architecture where
both can be extremely expensive.

We are proposing upstreaming a more palatable version of this to the
community, in the form of this proposal and accompanying patch.  We are
proposing the syntax _ExtInt(N).  We intend to propose this to the WG14
committee[1], and the underscore-capital seems like the active direction
for a WG14 paper's acceptance.  An alternative that Richard Smith
suggested on the initial review was __int(N), however we believe that
is much less acceptable by WG14.  We considered _Int, however _Int is
used as an identifier in libstdc++ and there is no good way to fall
back to an identifier (since _Int(5) is indistinguishable from an
unnamed initializer of a template type named _Int).

[0]https://www.intel.com/content/www/us/en/software/programmable/quartus-prime/hls-compiler.html)
[1]http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2472.pdf

Differential Revision: https://reviews.llvm.org/D73967
2020-04-17 07:10:57 -07:00
Serge Pavlov c7ff5b38f2 [FPEnv] Use single enum to represent rounding mode
Now compiler defines 5 sets of constants to represent rounding mode.
These are:

1. `llvm::APFloatBase::roundingMode`. It specifies all 5 rounding modes
defined by IEEE-754 and is used in `APFloat` implementation.

2. `clang::LangOptions::FPRoundingModeKind`. It specifies 4 of 5 IEEE-754
rounding modes and a special value for dynamic rounding mode. It is used
in clang frontend.

3. `llvm::fp::RoundingMode`. Defines the same values as
`clang::LangOptions::FPRoundingModeKind` but in different order. It is
used to specify rounding mode in in IR and functions that operate IR.

4. Rounding mode representation used by `FLT_ROUNDS` (C11, 5.2.4.2.2p7).
Besides constants for rounding mode it also uses a special value to
indicate error. It is convenient to use in intrinsic functions, as it
represents platform-independent representation for rounding mode. In this
role it is used in some pending patches.

5. Values like `FE_DOWNWARD` and other, which specify rounding mode in
library calls `fesetround` and `fegetround`. Often they represent bits
of some control register, so they are target-dependent. The same names
(not values) and a special name `FE_DYNAMIC` are used in
`#pragma STDC FENV_ROUND`.

The first 4 sets of constants are target independent and could have the
same numerical representation. It would simplify conversion between the
representations. Also now `clang::LangOptions::FPRoundingModeKind` and
`llvm::fp::RoundingMode` do not contain the value for IEEE-754 rounding
direction `roundTiesToAway`, although it is supported natively on
some targets.

This change defines all the rounding mode type via one `llvm::RoundingMode`,
which also contains rounding mode for IEEE rounding direction `roundTiesToAway`.

Differential Revision: https://reviews.llvm.org/D77379
2020-04-09 13:26:47 +07:00
Erich Keane 30588a7395 Make target features check work with ctor and dtor-
The problem was reported in PR45468, applying target features to an
always_inline constructor/destructor runs afoul of GlobalDecl
construction assert when checking for target-feature compatibility.

The core problem is fixed by using the version of the check that takes a
FunctionDecl rather than the GlobalDecl. However, while writing the
test, I discovered that source locations weren't properly set for this
check on ctors/dtors. This patch also fixes constructors and CALLED destructors.

Unfortunately, it doesn't seem too possible to get a meaningful source
location for a 'cleanup' destructor, so those are still 'frontend' level
errors unfortunately. A fixme was added to the test to cover that
situation.
2020-04-08 13:19:55 -07:00
Ian Levesque bb3111cbaf [clang][xray] Add xray attributes to functions without decls too
Summary: This allows instrumenting things like global initializers

Reviewers: dberris, MaskRay, smeenai

Subscribers: cfe-commits, johnislarry

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77191
2020-04-01 00:02:39 -04:00
Sander de Smalen 5087ace651 [Clang][SVE] Parse builtin type string for scalable vectors
This patch adds 'q' to mean 'scalable vector' in the builtin
type string, and for SVE will return the matching builtin
type as defined in the C/C++ language extensions for SVE.

This patch also adds some scaffolding to generate the arm_sve.h
header file, and some builtin definitions (+CodeGen) to be able
to implement some simple masked load intrinsics that use the
ACLE types, such as:

 svint8_t test_svld1_s8(svbool_t pg, const int8_t *base) {
   return svld1_s8(pg, base);
 }

Reviewers: efriedma, rjmccall, rovka, rsandifo-arm, rengolin

Reviewed By: efriedma

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75298
2020-03-15 14:34:52 +00:00
Yaxun (Sam) Liu fb44b9db95 [OpenCL][CUDA][HIP][SYCL] Add norecurse
norecurse function attr indicates the function is not called recursively
directly or indirectly.

Add norecurse to OpenCL functions, SYCL functions in device compilation
and CUDA/HIP kernels.

Although there is LLVM pass adding norecurse to functions, it only works
for whole-program compilation. Also FE adding norecurse can make that
pass run faster since functions with norecurse do not need to be checked
again.

Differential Revision: https://reviews.llvm.org/D73651
2020-02-16 20:41:00 -05:00
Fangrui Song 1d49eb00d9 [AsmPrinter] De-capitalize all AsmPrinter::Emit* but EmitInstruction
Similar to rL328848.
2020-02-13 17:06:24 -08:00
Johannes Doerfert 70cac41a2b Reapply "[OpenMP][IRBuilder] Perform finalization (incl. outlining) late"
Reapply 8a56d64d76 with minor fixes.

The problem was that cancellation can cause new edges to the parallel
region exit block which is not outlined. The CodeExtractor will encode
the information which "exit" was taken as a return value. The fix is to
ensure we do not return any value from the outlined function, to prevent
control to value conversion we ensure a single exit block for the
outlined region.

This reverts commit 3aac953afa.
2020-02-12 22:29:07 -06:00
Johannes Doerfert 3aac953afa Revert "[OpenMP][IRBuilder] Perform finalization (incl. outlining) late"
This reverts commit 8a56d64d76.

Will be recommitted once the clang test problem is addressed.
2020-02-12 18:50:43 -06:00
Johannes Doerfert 8a56d64d76 [OpenMP][IRBuilder] Perform finalization (incl. outlining) late
In order to fix PR44560 and to prepare for loop transformations we now
finalize a function late, which will also do the outlining late. The
logic is as before but the actual outlining step happens now after the
function was fully constructed. Once we have loop transformations we
can apply them in the finalize step before the outlining.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D74372
2020-02-12 17:55:01 -06:00
Ian Levesque 14f870366a [xray][clang] Always add xray-skip-entry/exit and xray-ignore-loops attrs
The function attributes xray-skip-entry, xray-skip-exit, and
xray-ignore-loops were only being applied if a function had an
xray-instrument attribute, but they should apply if xray is enabled
globally too.

Differential Revision: https://reviews.llvm.org/D73842
2020-02-11 14:00:41 -08:00
Fangrui Song 69bf40c45f [Driver][CodeGen] Support -fpatchable-function-entry=N,M and __attribute__((patchable_function_entry(N,M))) where M>0
Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D73072
2020-01-23 17:02:54 -08:00
Ian Levesque 97ba483026 [xray] Allow instrumenting only function entry and/or only function exit
Extend -fxray-instrumentation-bundle to split function-entry and
function-exit into two separate options, so that it is possible to
instrument only function entry or only function exit.  For use cases
that only care about one or the other this will save significant overhead
and code size.

Differential Revision: https://reviews.llvm.org/D72890
2020-01-17 13:32:34 -08:00