Leverage the InMemoryModuleCache to invalidate a module the first time
it fails to import (and to lock a module as soon as it's built or
imported successfully). For implicit module builds, this optimizes
importing deep graphs where the leaf module is out-of-date; see example
near the end of the commit message.
Previously the cache finalized ("locked in") all modules imported so far
when starting a new module build. This was sufficient to prevent
loading two versions of the same module, but was somewhat arbitrary and
hard to reason about.
Now the cache explicitly tracks module state, where each module must be
one of:
- Unknown: module not in the cache (yet).
- Tentative: module in the cache, but not yet fully imported.
- ToBuild: module found on disk could not be imported; need to build.
- Final: module in the cache has been successfully built or imported.
Preventing repeated failed imports avoids variation in builds based on
shifting filesystem state. Now it's guaranteed that a module is loaded
from disk exactly once. It now seems safe to remove
FileManager::invalidateCache, but I'm leaving that for a later commit.
The new, precise logic uncovered a pre-existing problem in the cache:
the map key is the module filename, and different contexts use different
filenames for the same PCM file. (In particular, the test
Modules/relative-import-path.c does not build without this commit.
r223577 started using a relative path to describe a module's base
directory when importing it within another module. As a result, the
module cache sees an absolute path when (a) building the module or
importing it at the top-level, and a relative path when (b) importing
the module underneath another one.)
The "obvious" fix is to resolve paths using FileManager::getVirtualFile
and change the map key for the cache to a FileEntry, but some contexts
(particularly related to ASTUnit) have a shorter lifetime for their
FileManager than the InMemoryModuleCache. This is worth pursuing
further in a later commit; perhaps by tying together the FileManager and
InMemoryModuleCache lifetime, or moving the in-memory PCM storage into a
VFS layer.
For now, use the PCM's base directory as-written for constructing the
filename to check the ModuleCache.
Example
=======
To understand the build optimization, first consider the build of a
module graph TU -> A -> B -> C -> D with an empty cache:
TU builds A'
A' builds B'
B' builds C'
C' builds D'
imports D'
B' imports C'
imports D'
A' imports B'
imports C'
imports D'
TU imports A'
imports B'
imports C'
imports D'
If we build TU again, where A, B, C, and D are in the cache and D is
out-of-date, we would previously get this build:
TU imports A
imports B
imports C
imports D (out-of-date)
TU builds A'
A' imports B
imports C
imports D (out-of-date)
builds B'
B' imports C
imports D (out-of-date)
builds C'
C' imports D (out-of-date)
builds D'
imports D'
B' imports C'
imports D'
A' imports B'
imports C'
imports D'
TU imports A'
imports B'
imports C'
imports D'
After this commit, we'll immediateley invalidate A, B, C, and D when we
first observe that D is out-of-date, giving this build:
TU imports A
imports B
imports C
imports D (out-of-date)
TU builds A' // The same graph as an empty cache.
A' builds B'
B' builds C'
C' builds D'
imports D'
B' imports C'
imports D'
A' imports B'
imports C'
imports D'
TU imports A'
imports B'
imports C'
imports D'
The new build matches what we'd naively expect, pretty closely matching
the original build with the empty cache.
rdar://problem/48545366
llvm-svn: 355778
Change MemoryBufferCache to InMemoryModuleCache, moving it from Basic to
Serialization. Another patch will start using it to manage module build
more explicitly, but this is split out because it's mostly mechanical.
Because of the move to Serialization we can no longer abuse the
Preprocessor to forward it to the ASTReader. Besides the rename and
file move, that means Preprocessor::Preprocessor has one fewer parameter
and ASTReader::ASTReader has one more.
llvm-svn: 355777
Add a remark for importing modules. Depending on whether this is a
direct import (into the TU being built by this compiler instance) or
transitive import (into an already-imported module), the diagnostic has
two forms:
importing module 'Foo' from 'path/to/Foo.pcm'
importing module 'Foo' into 'Bar' from 'path/to/Foo.pcm'
Also drop a redundant FileCheck invocation in Rmodule-build.m that was
using -Reverything, since the notes from -Rmodule-import were confusing
it.
https://reviews.llvm.org/D58891
llvm-svn: 355477
When a module name is specified as -fmodule-name, that module gets a
clang::Module object, but it won't actually be built or imported; it
will be textual. CGDebugInfo wouldn't detect this and them emit a
DICompileUnit that had a hash but no name and that confused both
dsymutil, LLDB, and myself.
rdar://problem/47926508
Differential Revision: https://reviews.llvm.org/D57976
llvm-svn: 353578
Some of these functions take some extraneous arguments, e.g. EltSize,
Offset, which are computable from the Type and DataLayout.
Add some asserts to ensure that the computed values are consistent
with the passed-in values, in preparation for eliminating the
extraneous arguments. This also asserts that the Type is an Array for
the calls named "Array" and a Struct for the calls named "Struct".
Then, correct a couple of errors:
1. Using CreateStructGEP on an array type. (this causes the majority
of the test differences, as struct GEPs are created with i32
indices, while array GEPs are created with i64 indices)
2. Passing the wrong Offset to CreateStructGEP in TargetInfo.cpp on
x86-64 NACL (which uses 32-bit pointers).
Differential Revision: https://reviews.llvm.org/D57766
llvm-svn: 353529
For global variables with unordered initialization that are instantiated
within a module, we previously did not emit the global (or its
initializer) at all unless it was used in the importing translation unit
(and sometimes not even then!), leading to misbehavior and link errors.
We now emit the initializer for an instantiated global variable with
unordered initialization with side-effects in a module into every
translation unit that imports the module. This is unfortunate, but
mostly matches the behavior of a non-modular compilation and seems to be
the best that we can reasonably do.
llvm-svn: 353240
When Clang/LLVM is built with the CLANG_DEFAULT_STD_CXX CMake macro that sets
the default standard to something other than C++14, there are a number of lit
tests that fail as they rely on the C++14 default.
This patch just adds the language standard option explicitly to such test cases.
Differential revision: https://reviews.llvm.org/D57581
llvm-svn: 353163
It is intended to disable _all_ warnings, even those upgraded to
errors via `-Werror=warningname` or `#pragma clang diagnostic error'
Fixes: https://llvm.org/PR38231
Differential Revision: https://reviews.llvm.org/D53199
llvm-svn: 352535
The autolinking extension for ELF uses a slightly different format for
encoding the autolink information compared to COFF and MachO. Account
for this in the CGM to ensure that we do not assert when emitting
assembly or an object file.
llvm-svn: 350476
This reverts commit r348280 and reapplies D55085 without modifications.
Original commit message:
Avoid emitting redundant or unusable directories in DIFile metadata entries.
As discussed on llvm-dev recently, Clang currently emits redundant
directories in DIFile entries, such as
.file 1 "/Volumes/Data/llvm" "/Volumes/Data/llvm/tools/clang/test/CodeGen/debug-info-abspath.c"
This patch looks at any common prefix between the compilation
directory and the (absolute) file path and strips the redundant
part. More importantly it leaves the compilation directory empty if
the two paths have no common prefix.
After this patch the above entry is (assuming a compilation dir of "/Volumes/Data/llvm/_build"):
.file 1 "/Volumes/Data/llvm" "tools/clang/test/CodeGen/debug-info-abspath.c"
When building the FileCheck binary with debug info, this patch makes
the build artifacts ~1kb smaller.
Differential Revision: https://reviews.llvm.org/D55085
llvm-svn: 348513
Friend function template defined in a class template becomes available if
the enclosing class template is instantiated. Until the function template
is used, it does not have a body, but still is considered a definition for
the purpose of redeclaration checks.
This change modifies redefinition check so that it can find the friend
function template definitions in instantiated classes.
Differential Revision: http://reviews.llvm.org/D21508
llvm-svn: 348473
This reverts commit r348154 and follow-up commits r348211 and r3248213.
Reason: the original commit broke compiler-rt tests and a follow-up fix
(r348203) broke our integrate and was reverted.
llvm-svn: 348280
As discussed on llvm-dev recently, Clang currently emits redundant
directories in DIFile entries, such as
.file 1 "/Volumes/Data/llvm" "/Volumes/Data/llvm/tools/clang/test/CodeGen/debug-info-abspath.c"
This patch looks at any common prefix between the compilation
directory and the (absolute) file path and strips the redundant
part. More importantly it leaves the compilation directory empty if
the two paths have no common prefix.
After this patch the above entry is (assuming a compilation dir of "/Volumes/Data/llvm/_build"):
.file 1 "/Volumes/Data/llvm" "tools/clang/test/CodeGen/debug-info-abspath.c"
When building the FileCheck binary with debug info, this patch makes
the build artifacts ~1kb smaller.
Differential Revision: https://reviews.llvm.org/D55085
llvm-svn: 348154
This patch passes -fdebug-prefix-map (a feature for renaming source
paths in the debug info) through to the per-module codegen options and
adds the debug prefix map to the module hash.
<rdar://problem/46045865>
Differential Revision: https://reviews.llvm.org/D55037
llvm-svn: 347926
Summary: The name of the synthesized constants for constant initialization was using mangling for statics, which isn't generally correct and (in a yet-uncommitted patch) causes the mangler to assert out because the static ends up trying to mangle function parameters and this makes no sense. Instead, mangle to `"__const." + FunctionName + "." + DeclName`.
Reviewers: rjmccall
Subscribers: dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D54055
llvm-svn: 346915
Include search paths can be relative paths. The loadSubdirectoryModuleMaps function
should account for that and respect the -working-directory parameter given to Clang.
rdar://46045849
Differential Revision: https://reviews.llvm.org/D54503
llvm-svn: 346822
The current version only emits the below error for a module (attempted to be loaded) from the `prebuilt-module-path`:
```
error: module file blabla.pcm cannot be loaded due to a configuration mismatch with the current compilation [-Wmodule-file-config-mismatch]
```
With this change, if the prebuilt module is used, we allow the proper diagnostic behind the configuration mismatch to be shown.
```
error: POSIX thread support was disabled in PCH file but is currently enabled
error: module file blabla.pcm cannot be loaded due to a configuration mismatch with the current compilation [-Wmodule-file-config-mismatch]
```
(A few lines later an error is emitted anyways, so there is no reason not to complain for configuration mismatches if a config mismatch is found and kills the build.)
Reviewed By: dblaikie
Tags: #clang
Differential Revision: https://reviews.llvm.org/D53334
llvm-svn: 346439
This reverts commit r345963. We have a path forward now.
Original commit message:
The driver accidentally stopped passing the input filenames on to -cc1
in this mode due to confusion over what action was being requested.
This change also fixes a couple of crashes I encountered when passing
multiple files to such a -cc1 invocation.
llvm-svn: 346130
This reverts commit r345803 and r345915 (a follow-up fix to r345803).
Reason: r345803 blocks our internal integrate because of the new
warnings showing up in too many places. The fix is actually correct,
we will reland it after figuring out how to integrate properly.
llvm-svn: 345963
-fsyntax-only.
The driver accidentally stopped passing the input filenames on to -cc1
in this mode due to confusion over what action was being requested.
This change also fixes a couple of crashes I encountered when passing
multiple files to such a -cc1 invocation.
llvm-svn: 345803
We haven't supported compiling ObjC1 for a long time (and never will again), so
there isn't any reason to keep these separate. This patch replaces
LangOpts::ObjC1 and LangOpts::ObjC2 with LangOpts::ObjC.
Differential revision: https://reviews.llvm.org/D53547
llvm-svn: 345637
'ignore-non-existent-contents' stopped working after r342232 in a way
that the actual attribute value isn't used and it works as if it is
always `true`.
Common use case for VFS iteration is iterating through files in umbrella
directories for modules. Ability to detect if some VFS entries point to
non-existing files is nice but non-critical. Instead of adding back
support for `'ignore-non-existent-contents': false` I am removing the
attribute, because such scenario isn't used widely enough and stricter
checks don't provide enough value to justify the maintenance.
rdar://problem/45176119
Reviewers: bruno
Reviewed By: bruno
Subscribers: hiraditya, dexonsmith, sammccall, cfe-commits
Differential Revision: https://reviews.llvm.org/D53228
llvm-svn: 345212
Before this patch, clang would emit a (module-)forward declaration for
template instantiations that are not anchored by an explicit template
instantiation, but still are guaranteed to be available in an imported
module. Unfortunately detecting the owning module doesn't reliably
work when local submodule visibility is enabled and the template is
inside a cross-module namespace.
This make clang debuggable again with -gmodules and LSV enabled.
rdar://problem/41552377
llvm-svn: 345109
Allows module map writers to add build requirements based on
platform/os. This helps when target features and language dialects
aren't enough to conditionalize building a module, among other things,
it allow module maps for different platforms to live in the same file.
rdar://problem/43909745
Differential Revision: https://reviews.llvm.org/D51910
llvm-svn: 342499
There is a bit of code at the end of AddDeclaration that should be run on
every exit of the function. However, there was an early exit beforehand
that could be triggered, which causes a small amount of data to skip the
hashing, leading to false positive mismatch. Use a separate function so
that this code is always run.
llvm-svn: 342199
submodule visibility is disabled.
Attempting to pick a specific declaration to make visible when the
module containing the merged declaration becomes visible is error-prone,
as we don't yet know which declaration we'll choose to be the definition
when we are informed of the merging.
This reinstates r342019, reverted in r342020. The regression previously
observed after this commit was fixed in r342096.
llvm-svn: 342097
submodule visibility is disabled.
Attempting to pick a specific declaration to make visible when the
module containing the merged declaration becomes visible is error-prone,
as we don't yet know which declaration we'll choose to be the definition
when we are informed of the merging.
llvm-svn: 342019
hidden definition with a would-be-parsed redefinition.
This permits a bunch of cleanups. In particular, we no longer need to
take merged definitions into account when checking declaration
visibility, only when checking definition visibility, which makes
certain visibility checks take linear instead of quadratic time.
We could also now remove the UPD_DECL_EXPORTED update record and track
on each declaration whether it was demoted from a definition (as we
already do for variables), but I'm not doing that in this patch to keep
the changes here simpler.
llvm-svn: 342018
Fix a bug in the deserialization of IMPORTS section and allow for
imported modules to also be printed with -module-file-info.
rdar://problem/43867753
llvm-svn: 341902
destructors.
We previously tried to patch up the exception specification after
completing the class, which went wrong when the exception specification
was needed within the class body (in particular, by a friend
redeclaration of the destructor in a nested class). We now mark the
destructor as having a not-yet-computed exception specification
immediately after creating it.
This requires delaying various checks against the exception
specification (where we'd previously have just got the wrong exception
specification, and now find we have an exception specification that we
can't compute yet) when those checks fire while the class is being
defined.
This also exposed an issue that we were missing a CodeSynthesisContext
for computation of exception specifications (otherwise we'd fail to make
the module containing the definition of the class visible when computing
its members' exception specs). Adding that incidentally also gives us a
diagnostic quality improvement.
This has also exposed an pre-existing problem: making the exception
specification evaluation context a non-SFINAE context (as it should be)
results in a bootstrap failure; PR38850 filed for this.
llvm-svn: 341499
This test uses enums, which have different behavior when targeting different
systems. Specifying a triple will give predictable behavior to this test.
llvm-svn: 341496
ASTContext::applyObjCProtocolQualifiers will return a canonical type when given
a canonical type and an array of canonical protocols. If the protocols are not
canonical then the returned type is also not canonical. Since a canonical type is needed, canonicalize the returned type before using it. This later prevents
a type from having a non-canonical canonical type.
llvm-svn: 341013
Changes the default Windows target triple returned by
GetHostTriple.cmake from the old environment names (which we wanted to
move away from) to newer, normalized ones. This also requires updating
all tests to use the new systems names in constraints.
Differential Revision: https://reviews.llvm.org/D47381
llvm-svn: 339307
Benjamin Kramer