Commit Graph

28666 Commits

Author SHA1 Message Date
Hsiangkai Wang
89ce644902 [Clang][RISCV] Add half-precision FP for vle16/vse16.
I missed to add half-precision FP types for vle16/vse16 in the previous
patches. Added them in this patch.

Differential Revision: https://reviews.llvm.org/D106340
2021-07-21 09:55:21 +08:00
Albion Fung
2fd1520247 [PowerPC] Implemented mtmsr, mfspr, mtspr Builtins
Implemented builtins for mtmsr, mfspr, mtspr on PowerPC;
the patch is intended for XL Compatibility.

Differential revision: https://reviews.llvm.org/D106130
2021-07-20 17:51:00 -05:00
Alex Lorenz
808bbc2c47 [clang][darwin] Add support for macOS -> Mac Catalyst
version remapping to the Darwin SDK Info

Differential Revision: https://reviews.llvm.org/D105958
2021-07-20 14:25:33 -07:00
Albion Fung
3434ac9e39 [PowerPC] Store, load, move from and to registers related builtins
This patch implements store, load, move from and to registers related
builtins, as well as the builtin for stfiw. The patch aims to provide
feature parady with xlC on AIX.

Differential revision: https://reviews.llvm.org/D105946
2021-07-20 15:46:14 -05:00
Melanie Blower
d48ad358b1 Revert "[CLANG][PATCH][FPEnv] Add support for option -ffp-eval-method and extend #pragma float_control similarly"
This reverts commit ce8024e8ff.
There are a couple buildbot problems
2021-07-20 16:40:55 -04:00
Alex Lorenz
05a6d74c48 [clang] NFC, move DarwinSDKInfo to lib/Basic
This is a preparation commit for https://reviews.llvm.org/D105958
2021-07-20 13:22:48 -07:00
Melanie Blower
ce8024e8ff [CLANG][PATCH][FPEnv] Add support for option -ffp-eval-method and extend #pragma float_control similarly
The Intel compiler ICC supports the option "-fp-model=(source|double|extended)"
which causes the compiler to use a wider type for intermediate floating point
calculations. Also supported is a way to embed this effect in the source
program with #pragma float_control(source|double|extended).
This patch extends pragma float_control syntax, and also adds support
for a new floating point option "-ffp-eval-method=(source|double|extended)".
source: intermediate results use source precision
double: intermediate results use double precision
extended: intermediate results use extended precision

Reviewed By: Aaron Ballman

Differential Revision: https://reviews.llvm.org/D93769
2021-07-20 16:02:09 -04:00
Alex Lorenz
a8262a383b [clang][darwin] add support for Mac Catalyst availability
This commit adds support for Mac Catalyst availability attribute, as
supported by the Apple clang compiler. A follow-up commit will provide
additional support for inferring Mac Catalyst availability from macOS
availability using the mapping in the SDKSettings.json.

Differential Revision: https://reviews.llvm.org/D105052
2021-07-20 12:51:57 -07:00
Victor Huang
1a762f93f8 [PowerPC] Add PowerPC cmpb builtin and emit target indepedent code for XL compatibility
This patch is in a series of patches to provide builtins for compatibility
with the XL compiler. This patch add the builtin and emit target independent
code for __cmpb.

Reviewed By: nemanjai, #powerpc

Differential revision: https://reviews.llvm.org/D105194
2021-07-20 13:06:22 -05:00
Jamie Schmeiser
9cb00b9ecb Reland Produce warning for performing pointer arithmetic on a null pointer.
Summary:
Test and produce warning for subtracting a pointer from null or subtracting
null from a pointer.

This reland adds the functionality that the warning is no longer reusing an
existing warning, it has different wording for C vs C++ to refect the fact
that nullptr-nullptr has defined behaviour in C++,  it is suppressed
when the warning is triggered by a system header and adds
-Wnull-pointer-subtraction to allow the warning to be controlled.  -Wextra
implies -Wnull-pointer-subtraction.

Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: efriedma (Eli Friedman), nickdesaulniers (Nick Desaulniers)
Differential Revision: https://reviews.llvm.org/D98798
2021-07-20 10:12:20 -04:00
Stefan Pintilie
02cd937945 [PowerPC][Builtins] Added a number of builtins for compatibility with XL.
Added a number of different builtins that exist in the XL compiler. Most of
these builtins already exist in clang under a different name.

Reviewed By: nemanjai, #powerpc

Differential Revision: https://reviews.llvm.org/D104386
2021-07-20 08:57:55 -05:00
Jan Svoboda
bc1a2979fc [clang][deps] Separate filesystem caches for minimized and original files
This patch separates the local and global caches of `DependencyScanningFilesystem` into two buckets: minimized files and original files. This is necessary to deal with precompiled modules/headers.

Consider a single worker with its instance of filesystem:
1. Build system uses the worker to scan dependencies of module A => filesystem cache gets populated with minimized input files.
2. Build system uses the results to explicitly build module A => explicitly built module captures the state of the real filesystem (containing non-minimized input files).
3. Build system uses the prebuilt module A as an explicit precompiled dependency for another compile job B.
4. Build system uses the same worker to scan dependencies for job B => worker uses implicit modular build to discover dependencies, which validates the filesystem state embedded in the prebuilt module (non-minimized files) to the current view of the filesystem (minimized files), resulting in validation failures.

This problem can be avoided in step 4 by collecting input files from the precompiled module and marking them as "ignored" in the minimizing filesystem. This way, the validation should succeed, since we should be always dealing with the original (non-minized) input files. However, the filesystem already minimized the input files in step 1 and put it in the cache, which gets used in step 4 as well even though it's marked ignored (do not minimize). This patch essentially fixes this oversight by making the `"file is minimized"` part of the cache key (from high level).

Depends on D106064.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D106146
2021-07-20 12:08:46 +02:00
Jan Svoboda
63fd109d3a [clang][deps] Normalize ignored filenames in minimizing file system
This patch normalizes filenames in `DependencyScanningWorkerFilesystem` so that lookup of ignored files works correctly on Windows (where `/` and `\` are equivalent).

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D106064
2021-07-20 11:31:31 +02:00
Hsiangkai Wang
0d22dee2ca [Clang][RISCV] Correct the alignment of stores generated by vlseg/vlsegff.
Differential Revision: https://reviews.llvm.org/D106255
2021-07-20 09:29:06 +08:00
Quinn Pham
0268e123be [PowerPC] swdiv_nochk Builtins for XL Compat
This patch is in a series of patches to provide builtins for
compatibility with the XL compiler. This patch adds software divide
builtins with no checking. These builtins are each emitted as a fast
fdiv.

Reviewed By: #powerpc, nemanjai

Differential Revision: https://reviews.llvm.org/D106150
2021-07-19 16:51:10 -05:00
Hsiangkai Wang
77bb82d068 [Clang][RISCV] Support half-precision floating point for RVV intrinsics.
Use _Float16 as the half-precision floating point type. Define a new
type specifier 'x' for the _Float16 type.

Differential Revision: https://reviews.llvm.org/D105001
2021-07-19 23:17:01 +08:00
Amy Kwan
dd5aa657a5 [PowerPC] Implement vector bool/pixel initialization under -faltivec-src-compat=xl
This patch implements the initialization of vectors under the
-faltivec-src-compat=xl option introduced in https://reviews.llvm.org/D103615.

Under this option, the initialization of scalar vectors, vector bool, and vector
pixel are treated the same, where the initialization value is splatted across
the whole vector.

This patch does not change the behaviour of the -faltivec-src-compat=mixed option,
which is the current default for Clang.

Differential Revision: https://reviews.llvm.org/D106120
2021-07-19 09:10:06 -05:00
Simon Tatham
cef56d58db [clang] Change set type used for SourceLocation.
This is part of a patch series working towards the ability to make
SourceLocation into a 64-bit type to handle larger translation units.

If clang is built for a 32-bit platform and SourceLocation is 64 bits
wide, then a SourceLocation will be larger than a pointer, so it won't
be possible to keep them in a SmallPtrSet any more. Switch to
SmallDenseSet instead.

Patch originally by Mikhail Maltsev.

Differential Revision: https://reviews.llvm.org/D105493
2021-07-19 13:36:36 +01:00
Deep Majumder
d825309352 [analyzer] Handle std::make_unique
Differential Revision: https://reviews.llvm.org/D103750
2021-07-18 19:54:28 +05:30
Lei Huang
c8937b6cb9 [PowerPC] Implement XL compact math builtins
Implement a subset of builtins required for compatiblilty with AIX XL compiler.

Reviewed By: nemanjai

Differential Revision: https://reviews.llvm.org/D105930
2021-07-16 13:21:13 -05:00
Zarko Todorovski
66225db98d [PowerPC][AIX] Add warning when alignment is incompatible with XL
https://reviews.llvm.org/D105659 implements ByVal handling in llc but
some cases are not compatible with existing XL compiler on AIX.  Adding
a clang warning for such cases.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D105660
2021-07-16 07:52:47 -04:00
Deep Majumder
48688257c5 [analyzer] Model comparision methods of std::unique_ptr
This patch handles all the comparision methods (defined via overloaded
operators) on std::unique_ptr. These operators compare the underlying
pointers, which is modelled by comparing the corresponding inner-pointer
SVal. There is also a special case for comparing the same pointer.

Differential Revision: https://reviews.llvm.org/D104616
2021-07-16 09:54:05 +05:30
Ben Barham
766a08df12 [Frontend] Only compile modules if not already finalized
It was possible to re-add a module to a shared in-memory module cache
when search paths are changed. This can eventually cause a crash if the
original module is referenced after this occurs.
  1. Module A depends on B
  2. B exists in two paths C and D
  3. First run only has C on the search path, finds A and B and loads
     them
  4. Second run adds D to the front of the search path. A is loaded and
     contains a reference to the already compiled module from C. But
     searching finds the module from D instead, causing a mismatch
  5. B and the modules that depend on it are considered out of date and
     thus rebuilt
  6. The recompiled module A is added to the in-memory cache, freeing
     the previously inserted one

This can never occur from a regular clang process, but is very easy to
do through the API - whether through the use of a shared case or just
running multiple compilations from a single `CompilerInstance`. Update
the compilation to return early if a module is already finalized so that
the pre-condition in the in-memory module cache holds.

Resolves rdar://78180255

Differential Revision: https://reviews.llvm.org/D105328
2021-07-15 18:27:08 -07:00
Victor Huang
4eb107ccba [PowerPC] Add PowerPC population count, reversed load and store related builtins and instrinsics for XL compatibility
This patch is in a series of patches to provide builtins for compatibility
with the XL compiler. This patch adds the builtins and instrisics for population
count, reversed load and store related operations.

Reviewed By: nemanjai, #powerpc

Differential revision: https://reviews.llvm.org/D106021
2021-07-15 17:23:56 -05:00
Artem Belevich
d774b4aa5e [NVPTX, CUDA] Add .and.popc variant of the b1 MMA instruction.
That should allow clang to compile mma.h from CUDA-11.3.

Differential Revision: https://reviews.llvm.org/D105384
2021-07-15 12:02:09 -07:00
Victor Huang
d40e8091bd [PowerPC] Add PowerPC rotate related builtins and emit target independent code for XL compatibility
This patch is in a series of patches to provide builtins for compatibility
with the XL compiler. This patch adds the builtins and emit target independent
code for rotate related operations.

Reviewed By: nemanjai, #powerpc

Differential revision: https://reviews.llvm.org/D104744
2021-07-15 10:23:54 -05:00
Anton Zabaznov
05eb59e1d0 [OpenCL] Add support of __opencl_c_program_scope_global_variables feature macro
Reviewed By: Anastasia

Differential Revision: https://reviews.llvm.org/D103191
2021-07-15 17:21:19 +03:00
liuke
034b94bb71 Fix documentation; NFC
The documentation about ignoringImpCasts is wrong, which can cause
misunderstandings. This patch fixes it.
2021-07-15 09:38:05 -04:00
Balázs Kéri
b0d38ad0bc [clang][Analyzer] Add symbol uninterestingness to bug report.
`PathSensitiveBughReport` has a function to mark a symbol as interesting but
it was not possible to clear this flag. This can be useful in some cases,
so the functionality is added.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D105637
2021-07-15 10:02:18 +02:00
Thomas Lively
4a4229f70f [WebAssembly] Codegen for v128.storeX_lane instructions
Replace the experimental clang builtins and LLVM intrinsics for these
instructions with normal codegen patterns. Resolves PR50435.

Differential Revision: https://reviews.llvm.org/D106019
2021-07-14 16:15:25 -07:00
Kirill Stoimenov
ac500fd18f [asan][clang] Add flag to outline instrumentation
Summary This option can be used to reduce the size of the
binary. The trade-off in this case would be the run-time
performance.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D105726
2021-07-14 13:36:34 -07:00
Thomas Lively
970e090010 [WebAssembly] Codegen for v128.loadX_lane instructions
Replace the experimental clang builtin and LLVM intrinsics for these
instructions with normal codegen patterns. Resolves PR50433.

Differential Revision: https://reviews.llvm.org/D105950
2021-07-14 11:31:53 -07:00
Aaron Ballman
aefd6c615c Combine two diagnostics into one and correct grammar
The anonymous and non-anonymous bit-field diagnostics are easily
combined into one diagnostic. However, the diagnostic was missing a
"the" that is present in the almost-identically worded
warn_bitfield_width_exceeds_type_width diagnostic, hence the changes to
test cases.
2021-07-14 11:43:28 -04:00
Zakk Chen
08cf69c31f [RISCV] Support overloading for RVV miscellaneous functions.
Based on this update to the intrinsic doc
https://github.com/riscv/rvv-intrinsic-doc/pull/103

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D105611
2021-07-13 21:35:37 -07:00
Victor Huang
18c19414eb [PowerPC] Add PowerPC compare and multiply related builtins and instrinsics for XL compatibility
This patch is in a series of patches to provide builtins for compatibility
with the XL compiler. This patch adds the builtins and instrisics for compare
and multiply related operations.

Reviewed By: nemanjai, #powerpc

Differential revision: https://reviews.llvm.org/D102875
2021-07-13 16:55:09 -05:00
Victor Huang
781929b423 [PowerPC][NFC] Power ISA features for Semachecking
[NFC] This patch adds features for pwr7, pwr8, and pwr9 that can be
used for semachecking builtin functions that are only valid for certain
versions of ppc.

Reviewed By: nemanjai, #powerpc
Authored By: Quinn Pham <Quinn.Pham@ibm.com>

Differential revision: https://reviews.llvm.org/D105501
2021-07-13 13:13:34 -05:00
Victor Huang
e4585d3f4e Revert "[PowerPC][NFC] Power ISA features for Semachecking"
This reverts commit 10e0cdfc65.
2021-07-13 13:13:34 -05:00
Victor Huang
10e0cdfc65 [PowerPC][NFC] Power ISA features for Semachecking
[NFC] This patch adds features for pwr7, pwr8, and pwr9 that can be
used for semachecking builtin functions that are only valid for certain
versions of ppc.

Reviewed By: nemanjai, #powerpc
Authored By: Quinn Pham <Quinn.Pham@ibm.com>

Differential revision: https://reviews.llvm.org/D105501
2021-07-13 10:51:25 -05:00
Anton Zabaznov
ab76101f40 [OpenCL] Add support of __opencl_c_read_write_images feature macro
This feature requires support of __opencl_c_images, so diagnostics for that is provided as well

Reviewed By: Anastasia

Differential Revision: https://reviews.llvm.org/D104915
2021-07-13 15:38:23 +03:00
Thomas Lively
cbabfc63b1 [WebAssembly] Custom combines for f32x4.demote_zero_f64x2
Replace the clang builtin function and LLVM intrinsic for
f32x4.demote_zero_f64x2 with combines from normal SDNodes. Also add missing
combines for i32x4.trunc_sat_zero_f64x2_{s,u}, which share the same pattern.

Differential Revision: https://reviews.llvm.org/D105755
2021-07-12 10:32:18 -07:00
Albion Fung
ef49d925e2 [PowerPC] Implement trap and conversion builtins for XL compatibility
This patch implements trap and FP to and from double conversions. The builtins
generate code that mirror what is generated from the XL compiler. Intrinsics
are named conventionally with builtin_ppc, but are aliased to provide the same
builtin names as the XL compiler.

Differential Revision: https://reviews.llvm.org/D103668
2021-07-12 11:04:17 -05:00
Vassil Vassilev
11b47c103a Reland "[clang-repl] Implement partial translation units and error recovery."
Original commit message:

[clang-repl] Implement partial translation units and error recovery.

https://reviews.llvm.org/D96033 contained a discussion regarding efficient
modeling of error recovery. @rjmccall has outlined the key ideas:

Conceptually, we can split the translation unit into a sequence of partial
translation units (PTUs). Every declaration will be associated with a unique PTU
that owns it.

The first key insight here is that the owning PTU isn't always the "active"
(most recent) PTU, and it isn't always the PTU that the declaration
"comes from". A new declaration (that isn't a redeclaration or specialization of
anything) does belong to the active PTU. A template specialization, however,
belongs to the most recent PTU of all the declarations in its signature - mostly
that means that it can be pulled into a more recent PTU by its template
arguments.

The second key insight is that processing a PTU might extend an earlier PTU.
Rolling back the later PTU shouldn't throw that extension away. For example, if
the second PTU defines a template, and the third PTU requires that template to
be instantiated at float, that template specialization is still part of the
second PTU. Similarly, if the fifth PTU uses an inline function belonging to the
fourth, that definition still belongs to the fourth. When we go to emit code in
a new PTU, we map each declaration we have to emit back to its owning PTU and
emit it in a new module for just the extensions to that PTU. We keep track of
all the modules we've emitted for a PTU so that we can unload them all if we
decide to roll it back.

Most declarations/definitions will only refer to entities from the same or
earlier PTUs. However, it is possible (primarily by defining a
previously-declared entity, but also through templates or ADL) for an entity
that belongs to one PTU to refer to something from a later PTU. We will have to
keep track of this and prevent unwinding to later PTU when we recognize it.
Fortunately, this should be very rare; and crucially, we don't have to do the
bookkeeping for this if we've only got one PTU, e.g. in normal compilation.
Otherwise, PTUs after the first just need to record enough metadata to be able
to revert any changes they've made to declarations belonging to earlier PTUs,
e.g. to redeclaration chains or template specialization lists.

It should even eventually be possible for PTUs to provide their own slab
allocators which can be thrown away as part of rolling back the PTU. We can
maintain a notion of the active allocator and allocate things like Stmt/Expr
nodes in it, temporarily changing it to the appropriate PTU whenever we go to do
something like instantiate a function template. More care will be required when
allocating declarations and types, though.

We would want the PTU to be efficiently recoverable from a Decl; I'm not sure
how best to do that. An easy option that would cover most declarations would be
to make multiple TranslationUnitDecls and parent the declarations appropriately,
but I don't think that's good enough for things like member function templates,
since an instantiation of that would still be parented by its original class.
Maybe we can work this into the DC chain somehow, like how lexical DCs are.

We add a different kind of translation unit `TU_Incremental` which is a
complete translation unit that we might nonetheless incrementally extend later.
Because it is complete (and we might want to generate code for it), we do
perform template instantiation, but because it might be extended later, we don't
warn if it declares or uses undefined internal-linkage symbols.

This patch teaches clang-repl how to recover from errors by disconnecting the
most recent PTU and update the primary PTU lookup tables. For instance:

```./clang-repl
clang-repl> int i = 12; error;
In file included from <<< inputs >>>:1:
input_line_0:1:13: error: C++ requires a type specifier for all declarations
int i = 12; error;
            ^
error: Parsing failed.
clang-repl> int i = 13; extern "C" int printf(const char*,...);
clang-repl> auto r1 = printf("i=%d\n", i);
i=13
clang-repl> quit
```

Differential revision: https://reviews.llvm.org/D104918
2021-07-12 15:21:22 +00:00
Corentin Jabot
8747234032 Partially implement P1401R5 (Narrowing contextual conversions to bool)
Support Narrowing conversions to bool in if constexpr condition
under C++23 language mode.

Only if constexpr is implemented as the behavior of static_assert
is already conforming. Still need to work on explicit(bool) to
complete support.
2021-07-12 08:06:27 -04:00
Aaron Ballman
f042e0a0f8 Fix the Clang documentation builder; NFC.
It was broken three days ago by the changes in D95561.
2021-07-12 07:59:18 -04:00
Aaron Ballman
de59f56440 [OpenMP] Support OpenMP 5.1 attributes
OpenMP 5.1 added support for writing OpenMP directives using [[]]
syntax in addition to using #pragma and this introduces support for the
new syntax.

In OpenMP, the attributes take one of two forms:
[[omp::directive(...)]] or [[omp::sequence(...)]]. A directive
attribute contains an OpenMP directive clause that is identical to the
analogous #pragma syntax. A sequence attribute can contain either
sequence or directive arguments and is used to ensure that the
attributes are processed sequentially for situations where the order of
the attributes matter (remember:
https://eel.is/c++draft/dcl.attr.grammar#4.sentence-4).

The approach taken here is somewhat novel and deserves mention. We
could refactor much of the OpenMP parsing logic to work for either
pragma annotation tokens or for attribute clauses. It would be a fair
amount of effort to share the logic for both, but it's certainly
doable. However, the semantic attribute system is not designed to
handle the arbitrarily complex arguments that OpenMP directives
contain. Adding support to thread the novel parsed information until we
can produce a semantic attribute would be considerably more effort.
What's more, existing OpenMP constructs are not (often) represented as
semantic attributes. So doing this through Attr.td would be a massive
undertaking that would likely only benefit OpenMP and comes with
additional risks. Rather than walk down that path, I am taking
advantage of the fact that the syntax of the directives within the
directive clause is identical to that of the #pragma form. Once the
parser recognizes that we're processing an OpenMP attribute, it caches
all of the directive argument tokens and then replays them as though
the user wrote a pragma. This reuses the same OpenMP parsing and
semantic logic directly, but does come with a risk if the OpenMP
committee decides to purposefully diverge their pragma and attribute
syntaxes. So, despite this being a novel approach that does token
replay, I think it's actually a better approach than trying to do this
through the declarative syntax in Attr.td.
2021-07-12 06:51:19 -04:00
Balazs Benics
d3e14fafc6 [analyzer][NFC] Display the correct function name even in crash dumps
The `-analyzer-display-progress` displayed the function name of the
currently analyzed function. It differs in C and C++. In C++, it
prints the argument types as well in a comma-separated list.
While in C, only the function name is displayed, without the brackets.
E.g.:

  C++: foo(), foo(int, float)
  C:   foo

In crash traces, the analyzer dumps the location contexts, but the
string is not enough for `-analyze-function` in C++ mode.
This patch addresses the issue by dumping the proper function names
even in stack traces.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D105708
2021-07-12 09:06:46 +02:00
Vassil Vassilev
5922f234c8 Revert "[clang-repl] Implement partial translation units and error recovery."
This reverts commit 6775fc6ffa.

It also reverts "[lldb] Fix compilation by adjusting to the new ASTContext signature."

This reverts commit 03a3f86071.

We see some failures on the lldb infrastructure, these changes might play a role
in it. Let's revert it now and see if the bots will become green.

Ref: https://reviews.llvm.org/D104918
2021-07-11 14:40:10 +00:00
Vassil Vassilev
6775fc6ffa [clang-repl] Implement partial translation units and error recovery.
https://reviews.llvm.org/D96033 contained a discussion regarding efficient
modeling of error recovery. @rjmccall has outlined the key ideas:

Conceptually, we can split the translation unit into a sequence of partial
translation units (PTUs). Every declaration will be associated with a unique PTU
that owns it.

The first key insight here is that the owning PTU isn't always the "active"
(most recent) PTU, and it isn't always the PTU that the declaration
"comes from". A new declaration (that isn't a redeclaration or specialization of
anything) does belong to the active PTU. A template specialization, however,
belongs to the most recent PTU of all the declarations in its signature - mostly
that means that it can be pulled into a more recent PTU by its template
arguments.

The second key insight is that processing a PTU might extend an earlier PTU.
Rolling back the later PTU shouldn't throw that extension away. For example, if
the second PTU defines a template, and the third PTU requires that template to
be instantiated at float, that template specialization is still part of the
second PTU. Similarly, if the fifth PTU uses an inline function belonging to the
fourth, that definition still belongs to the fourth. When we go to emit code in
a new PTU, we map each declaration we have to emit back to its owning PTU and
emit it in a new module for just the extensions to that PTU. We keep track of
all the modules we've emitted for a PTU so that we can unload them all if we
decide to roll it back.

Most declarations/definitions will only refer to entities from the same or
earlier PTUs. However, it is possible (primarily by defining a
previously-declared entity, but also through templates or ADL) for an entity
that belongs to one PTU to refer to something from a later PTU. We will have to
keep track of this and prevent unwinding to later PTU when we recognize it.
Fortunately, this should be very rare; and crucially, we don't have to do the
bookkeeping for this if we've only got one PTU, e.g. in normal compilation.
Otherwise, PTUs after the first just need to record enough metadata to be able
to revert any changes they've made to declarations belonging to earlier PTUs,
e.g. to redeclaration chains or template specialization lists.

It should even eventually be possible for PTUs to provide their own slab
allocators which can be thrown away as part of rolling back the PTU. We can
maintain a notion of the active allocator and allocate things like Stmt/Expr
nodes in it, temporarily changing it to the appropriate PTU whenever we go to do
something like instantiate a function template. More care will be required when
allocating declarations and types, though.

We would want the PTU to be efficiently recoverable from a Decl; I'm not sure
how best to do that. An easy option that would cover most declarations would be
to make multiple TranslationUnitDecls and parent the declarations appropriately,
but I don't think that's good enough for things like member function templates,
since an instantiation of that would still be parented by its original class.
Maybe we can work this into the DC chain somehow, like how lexical DCs are.

We add a different kind of translation unit `TU_Incremental` which is a
complete translation unit that we might nonetheless incrementally extend later.
Because it is complete (and we might want to generate code for it), we do
perform template instantiation, but because it might be extended later, we don't
warn if it declares or uses undefined internal-linkage symbols.

This patch teaches clang-repl how to recover from errors by disconnecting the
most recent PTU and update the primary PTU lookup tables. For instance:

```./clang-repl
clang-repl> int i = 12; error;
In file included from <<< inputs >>>:1:
input_line_0:1:13: error: C++ requires a type specifier for all declarations
int i = 12; error;
            ^
error: Parsing failed.
clang-repl> int i = 13; extern "C" int printf(const char*,...);
clang-repl> auto r1 = printf("i=%d\n", i);
i=13
clang-repl> quit
```

Differential revision: https://reviews.llvm.org/D104918
2021-07-11 10:23:41 +00:00
Thomas Lively
e5220104d0 [WebAssembly] Custom combines for f64x2.promote_low_f32x4
Replace the clang builtin function and LLVM intrinsic previously used to select
the f64x2.promote_low_f32x4 instruction with custom combines from standard
SelectionDAG nodes. Implement the new combines to share code with the similar
combines for f64x2.convert_low_i32x4_{s,u}. Resolves PR50232.

Differential Revision: https://reviews.llvm.org/D105675
2021-07-09 18:59:29 -07:00
Varun Gandhi
92dcb1d2db [Clang] Introduce Swift async calling convention.
This change is intended as initial setup. The plan is to add
more semantic checks later. I plan to update the documentation
as more semantic checks are added (instead of documenting the
details up front). Most of the code closely mirrors that for
the Swift calling convention. Three places are marked as
[FIXME: swiftasynccc]; those will be addressed once the
corresponding convention is introduced in LLVM.

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D95561
2021-07-09 11:50:10 -07:00