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* [IRGen] Evaluate constant static variables referenced through memberAlex Lorenz2017-08-251-18/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | expressions C++ allows us to reference static variables through member expressions. Prior to this commit, non-integer static variables that were referenced using a member expression were always emitted using lvalue loads. The old behaviour introduced an inconsistency between regular uses of static variables and member expressions uses. For example, the following program compiled and linked successfully: struct Foo { constexpr static const char *name = "foo"; }; int main() { return Foo::name[0] == 'f'; } but this program failed to link because "Foo::name" wasn't found: struct Foo { constexpr static const char *name = "foo"; }; int main() { Foo f; return f.name[0] == 'f'; } This commit ensures that constant static variables referenced through member expressions are emitted in the same way as ordinary static variable references. rdar://33942261 Differential Revision: https://reviews.llvm.org/D36876 llvm-svn: 311772
* PR22877: When constructing an array via a constructor with a default argumentRichard Smith2017-05-111-6/+14
| | | | | | | | | | | | in list-initialization, run cleanups for the default argument after each iteration of the initialization loop. We previously only ran the destructor for any temporary once, at the end of the complete loop, rather than once per iteration! Re-commit of r302750, reverted in r302776. llvm-svn: 302817
* Revert "PR22877: When constructing an array via a constructor with a default ↵Diana Picus2017-05-111-14/+6
| | | | | | | | | | | | | | | | | | | | | | | argument in list-initialization, run cleanups for the default argument after each iteration of the initialization loop." Revert "clang/test/CodeGenCXX/array-default-argument.cpp: Satisfy targets that have x86_thiscallcc." This reverts commit r302750 and its fixup r302757 because the test is still breaking on some of the ARM bots. array-default-argument.cpp:20:12: error: expected string not found in input // CHECK: {{call|invoke}}[[THISCALL:( x86_thiscallcc)?]] void @_ZN1AC1Ev([[TEMPORARY:.*]]) ^ <stdin>:18:1: note: scanning from here arrayctor.loop: ; preds = %arrayctor.loop, %entry ^ <stdin>:28:2: note: possible intended match here call void @_Z1fv() ^ -- llvm-svn: 302776
* PR22877: When constructing an array via a constructor with a default argumentRichard Smith2017-05-111-6/+14
| | | | | | | | | | in list-initialization, run cleanups for the default argument after each iteration of the initialization loop. We previously only ran the destructor for any temporary once, at the end of the complete loop, rather than once per iteration! llvm-svn: 302750
* Spelling mistakes in comments. NFCI. (PR27635)Simon Pilgrim2017-03-301-1/+1
| | | | llvm-svn: 299083
* [coroutines] Add codegen for await and yield expressionsGor Nishanov2017-03-261-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Details: Emit suspend expression which roughly looks like: auto && x = CommonExpr(); if (!x.await_ready()) { llvm_coro_save(); x.await_suspend(...); (*) llvm_coro_suspend(); (**) } x.await_resume(); where the result of the entire expression is the result of x.await_resume() (*) If x.await_suspend return type is bool, it allows to veto a suspend: if (x.await_suspend(...)) llvm_coro_suspend(); (**) llvm_coro_suspend() encodes three possible continuations as a switch instruction: %where-to = call i8 @llvm.coro.suspend(...) switch i8 %where-to, label %coro.ret [ ; jump to epilogue to suspend i8 0, label %yield.ready ; go here when resumed i8 1, label %yield.cleanup ; go here when destroyed ] llvm-svn: 298784
* Fix problems in "[OpenCL] Enabling the usage of CLK_NULL_QUEUE as compare ↵Egor Churaev2016-12-231-0/+1
| | | | | | | | | | | | | | operand." Summary: Fixed warnings in commit: https://reviews.llvm.org/rL290171 Reviewers: djasper, Anastasia Subscribers: yaxunl, cfe-commits, bader Differential Revision: https://reviews.llvm.org/D27981 llvm-svn: 290431
* Revert "[OpenCL] Enabling the usage of CLK_NULL_QUEUE as compare operand."Daniel Jasper2016-12-201-1/+0
| | | | | | | | | | This reverts commit r290171. It triggers a bunch of warnings, because the new enumerator isn't handled in all switches. We want a warning-free build. Replied on the commit with more details. llvm-svn: 290173
* [OpenCL] Enabling the usage of CLK_NULL_QUEUE as compare operand.Egor Churaev2016-12-201-0/+1
| | | | | | | | | | | | Summary: Enabling the compression of CLK_NULL_QUEUE to variable of type queue_t. Reviewers: Anastasia Subscribers: cfe-commits, yaxunl, bader Differential Revision: https://reviews.llvm.org/D27569 llvm-svn: 290171
* Re-commit r289252 and r289285, and fix PR31374Yaxun Liu2016-12-151-1/+2
| | | | llvm-svn: 289787
* Revert 289252 (and follow-up 289285), it caused PR31374Nico Weber2016-12-141-2/+1
| | | | llvm-svn: 289713
* When emitting a multidimensional array copy, only emit a single flattenedRichard Smith2016-12-141-9/+26
| | | | | | cleanup loop for exception handling. llvm-svn: 289623
* Remove custom handling of array copies in lambda by-value array capture andRichard Smith2016-12-141-20/+17
| | | | | | | | | | | copy constructors of classes with array members, instead using ArrayInitLoopExpr to represent the initialization loop. This exposed a bug in the static analyzer where it was unable to differentiate between zero-initialized and unknown array values, which has also been fixed here. llvm-svn: 289618
* Add two new AST nodes to represent initialization of an array in terms ofRichard Smith2016-12-121-0/+80
| | | | | | | | | | | | | | | | | | | | initialization of each array element: * ArrayInitLoopExpr is a prvalue of array type with two subexpressions: a common expression (an OpaqueValueExpr) that represents the up-front computation of the source of the initialization, and a subexpression representing a per-element initializer * ArrayInitIndexExpr is a prvalue of type size_t representing the current position in the loop This will be used to replace the creation of explicit index variables in lambda capture of arrays and copy/move construction of classes with array elements, and also C++17 structured bindings of arrays by value (which inexplicably allow copying an array by value, unlike all of C++'s other array declarations). No uses of these nodes are introduced by this change, however. llvm-svn: 289413
* Add support for non-zero null pointer for C and OpenCLYaxun Liu2016-12-091-1/+2
| | | | | | | | | | | | | | | | | | In amdgcn target, null pointers in global, constant, and generic address space take value 0 but null pointers in private and local address space take value -1. Currently LLVM assumes all null pointers take value 0, which results in incorrectly translated IR. To workaround this issue, instead of emit null pointers in local and private address space, a null pointer in generic address space is emitted and casted to local and private address space. Tentative definition of global variables with non-zero initializer will have weak linkage instead of common linkage since common linkage requires zero initializer and does not have explicit section to hold the non-zero value. Virtual member functions getNullPointer and performAddrSpaceCast are added to TargetCodeGenInfo which by default returns ConstantPointerNull and emitting addrspacecast instruction. A virtual member function getNullPointerValue is added to TargetInfo which by default returns 0. Each target can override these virtual functions to get target specific null pointer and the null pointer value for specific address space, and perform specific translations for addrspacecast. Wrapper functions getNullPointer is added to CodegenModule and getTargetNullPointerValue is added to ASTContext to facilitate getting the target specific null pointers and their values. This change has no effect on other targets except amdgcn target. Other targets can provide support of non-zero null pointer in a similar way. This change only provides support for non-zero null pointer for C and OpenCL. Supporting for other languages will be added later incrementally. Differential Revision: https://reviews.llvm.org/D26196 llvm-svn: 289252
* [c++17] P0135R1: Guaranteed copy elision.Richard Smith2016-12-061-13/+3
| | | | | | | | When an object of class type is initialized from a prvalue of the same type (ignoring cv qualifications), use the prvalue to initialize the object directly instead of inserting a redundant elidable call to a copy constructor. llvm-svn: 288866
* [OpenCL] Generate opaque type for sampler_t and function call for the ↵Yaxun Liu2016-07-281-0/+1
| | | | | | | | | | | | | | | | initializer Currently Clang use int32 to represent sampler_t, which have been a source of issue for some backends, because in some backends sampler_t cannot be represented by int32. They have to depend on kernel argument metadata and use IPA to find the sampler arguments and global variables and transform them to target specific sampler type. This patch uses opaque pointer type opencl.sampler_t* for sampler_t. For each use of file-scope sampler variable, it generates a function call of __translate_sampler_initializer. For each initialization of function-scope sampler variable, it generates a function call of __translate_sampler_initializer. Each builtin library can implement its own __translate_sampler_initializer(). Since the real sampler type tends to be architecture dependent, allowing it to be initialized by a library function simplifies backend design. A typical implementation of __translate_sampler_initializer could be a table lookup of real sampler literal values. Since its argument is always a literal, the returned pointer is known at compile time and easily optimized to finally become some literal values directly put into image read instructions. This patch is partially based on Alexey Sotkin's work in Khronos Clang (https://github.com/KhronosGroup/SPIR/commit/3d4eec61623502fc306e8c67c9868be2b136e42b). Differential Revision: https://reviews.llvm.org/D21567 llvm-svn: 277024
* P0136R1, DR1573, DR1645, DR1715, DR1736, DR1903, DR1941, DR1959, DR1991:Richard Smith2016-06-281-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace inheriting constructors implementation with new approach, voted into C++ last year as a DR against C++11. Instead of synthesizing a set of derived class constructors for each inherited base class constructor, we make the constructors of the base class visible to constructor lookup in the derived class, using the normal rules for using-declarations. For constructors, UsingShadowDecl now has a ConstructorUsingShadowDecl derived class that tracks the requisite additional information. We create shadow constructors (not found by name lookup) in the derived class to model the actual initialization, and have a new expression node, CXXInheritedCtorInitExpr, to model the initialization of a base class from such a constructor. (This initialization is special because it performs real perfect forwarding of arguments.) In cases where argument forwarding is not possible (for inalloca calls, variadic calls, and calls with callee parameter cleanup), the shadow inheriting constructor is not emitted and instead we directly emit the initialization code into the caller of the inherited constructor. Note that this new model is not perfectly compatible with the old model in some corner cases. In particular: * if B inherits a private constructor from A, and C uses that constructor to construct a B, then we previously required that A befriends B and B befriends C, but the new rules require A to befriend C directly, and * if a derived class has its own constructors (and so its implicit default constructor is suppressed), it may still inherit a default constructor from a base class llvm-svn: 274049
* Fix -Werror build.Richard Smith2016-03-081-1/+1
| | | | llvm-svn: 262965
* P0017R1: In C++1z, an aggregate class can have (public non-virtual) base ↵Richard Smith2016-03-081-6/+36
| | | | | | classes; these are initialized as if they were data members. llvm-svn: 262963
* Default vaarg lowering should support indirect struct types.James Y Knight2016-02-241-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes PR11517 for SPARC. On most targets, clang lowers va_arg itself, eschewing the use of the llvm vaarg instruction. This is necessary (at least for now) as the type argument to the vaarg instruction cannot represent all the ABI information that is needed to support complex calling conventions. However, on targets with a simpler varrags ABIs, the LLVM instruction can work just fine, and clang can simply lower to it. Unfortunately, even on such targets, vaarg with a struct argument would fail, because the default lowering to vaarg was naive: it didn't take into account the ABI attribute computed by classifyArgumentType. In particular, for the DefaultABIInfo, structs are supposed to be passed indirectly and so llvm's vaarg instruction should be emitted with a pointer argument. Now, vaarg instruction emission is able to use computed ABIArgInfo for the provided argument type, which allows the default ABI support to work for structs too. I haven't touched the EmitVAArg implementation for PPC32_SVR4 or XCore, although I believe both are now redundant, and could be switched over to use the default implementation as well. Differential Revision: http://reviews.llvm.org/D16154 llvm-svn: 261717
* [Bugfix] Fix ICE on constexpr vector splat.George Burgess IV2016-01-131-0/+1
| | | | | | | | | | | | | In {CG,}ExprConstant.cpp, we weren't treating vector splats properly. This patch makes us treat splats more properly. Additionally, this patch adds a new cast kind which allows a bool->int cast to result in -1 or 0, instead of 1 or 0 (for true and false, respectively), so we can sanely model OpenCL bool->int casts in the AST. Differential Revision: http://reviews.llvm.org/D14877 llvm-svn: 257559
* Atomics: support __c11_* calls on _Atomic struct types.Tim Northover2015-11-091-1/+2
| | | | | | | | | | | | | When a struct's size is not a power of 2, the corresponding _Atomic() type is promoted to the nearest. We already correctly handled normal C++ expressions of this form, but direct calls to the __c11_atomic_whatever builtins ended up performing dodgy operations on the smaller non-atomic types (e.g. memcpy too much). Later optimisations removed this as undefined behaviour. This patch converts EmitAtomicExpr to allocate its temporaries at the full atomic width, sidestepping the issue. llvm-svn: 252507
* [DEBUG INFO] Emit debug info for type used in explicit cast only.Alexey Bataev2015-10-201-0/+2
| | | | | | | Currently debug info for types used in explicit cast only is not emitted. It happened after a patch for better alignment handling. This patch fixes this bug. Differential Revision: http://reviews.llvm.org/D13582 llvm-svn: 250795
* Support __builtin_ms_va_list.Charles Davis2015-09-171-2/+2
| | | | | | | | | | | | | | | | | | Summary: This change adds support for `__builtin_ms_va_list`, a GCC extension for variadic `ms_abi` functions. The existing `__builtin_va_list` support is inadequate for this because `va_list` is defined differently in the Win64 ABI vs. the System V/AMD64 ABI. Depends on D1622. Reviewers: rsmith, rnk, rjmccall CC: cfe-commits Differential Revision: http://reviews.llvm.org/D1623 llvm-svn: 247941
* Compute and preserve alignment more faithfully in IR-generation.John McCall2015-09-081-98/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce an Address type to bundle a pointer value with an alignment. Introduce APIs on CGBuilderTy to work with Address values. Change core APIs on CGF/CGM to traffic in Address where appropriate. Require alignments to be non-zero. Update a ton of code to compute and propagate alignment information. As part of this, I've promoted CGBuiltin's EmitPointerWithAlignment helper function to CGF and made use of it in a number of places in the expression emitter. The end result is that we should now be significantly more correct when performing operations on objects that are locally known to be under-aligned. Since alignment is not reliably tracked in the type system, there are inherent limits to this, but at least we are no longer confused by standard operations like derived-to-base conversions and array-to-pointer decay. I've also fixed a large number of bugs where we were applying the complete-object alignment to a pointer instead of the non-virtual alignment, although most of these were hidden by the very conservative approach we took with member alignment. Also, because IRGen now reliably asserts on zero alignments, we should no longer be subject to an absurd but frustrating recurring bug where an incomplete type would report a zero alignment and then we'd naively do a alignmentAtOffset on it and emit code using an alignment equal to the largest power-of-two factor of the offset. We should also now be emitting much more aggressive alignment attributes in the presence of over-alignment. In particular, field access now uses alignmentAtOffset instead of min. Several times in this patch, I had to change the existing code-generation pattern in order to more effectively use the Address APIs. For the most part, this seems to be a strict improvement, like doing pointer arithmetic with GEPs instead of ptrtoint. That said, I've tried very hard to not change semantics, but it is likely that I've failed in a few places, for which I apologize. ABIArgInfo now always carries the assumed alignment of indirect and indirect byval arguments. In order to cut down on what was already a dauntingly large patch, I changed the code to never set align attributes in the IR on non-byval indirect arguments. That is, we still generate code which assumes that indirect arguments have the given alignment, but we don't express this information to the backend except where it's semantically required (i.e. on byvals). This is likely a minor regression for those targets that did provide this information, but it'll be trivial to add it back in a later patch. I partially punted on applying this work to CGBuiltin. Please do not add more uses of the CreateDefaultAligned{Load,Store} APIs; they will be going away eventually. llvm-svn: 246985
* Don't use unreachable as a placeholder, it confuses EmitBlockReid Kleckner2015-09-041-1/+3
| | | | | | | | | | This fixes an issue raised in D12412, where we generated invalid IR. Thanks to Vedant Kumar for coming up with the initial work around. Differential Revision: http://reviews.llvm.org/D12412 llvm-svn: 246880
* Implementing C99 partial re-initialization behavior (DR-253)Yunzhong Gao2015-06-101-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | Based on previous discussion on the mailing list, clang currently lacks support for C99 partial re-initialization behavior: Reference: http://lists.cs.uiuc.edu/pipermail/cfe-dev/2013-April/029188.html Reference: http://www.open-std.org/jtc1/sc22/wg14/www/docs/dr_253.htm This patch attempts to fix this problem. Given the following code snippet, struct P1 { char x[6]; }; struct LP1 { struct P1 p1; }; struct LP1 l = { .p1 = { "foo" }, .p1.x[2] = 'x' }; // this example is adapted from the example for "struct fred x[]" in DR-253; // currently clang produces in l: { "\0\0x" }, // whereas gcc 4.8 produces { "fox" }; // with this fix, clang will also produce: { "fox" }; Differential Review: http://reviews.llvm.org/D5789 llvm-svn: 239446
* [CodeGen] Reuse stack space from unused function results (with more accurate ↵Leny Kholodov2015-06-081-5/+6
| | | | | | | | | | unused result detection) This patch fixes issues with unused result detection which were found in patch http://reviews.llvm.org/D9743. Differential Revision: http://reviews.llvm.org/D10042 llvm-svn: 239294
* Evaluate union cast subexpressions when the cast value is unusedReid Kleckner2015-05-201-1/+6
| | | | | | Fixes PR23597. llvm-svn: 237839
* Fix for aggregate copying of variable length arrays.Alexey Bataev2015-05-201-13/+30
| | | | | | | | | | | | | Patch fixes codegen for aggregate copying of VLAs. Currently method CodeGenFunction::EmitAggregateCopy() does not support copying of VLAs. Patch checks if the size of the type is 0, then checks if the type is actually a variable-length array. Then it calculates total length for this array and calculates total size of the array in bytes: <total number of elements in array> * aligned_sizeof(ElementType) (if copy assignment is requested). If simple copying is requested, size is calculated like: <total number of elements in array> * aligned_sizeof(ElementType) - aligned_sizeof(ElementType) + sizeof(ElementType). memcpy() is used with this calculated size of the VLA. Differential Revision: http://reviews.llvm.org/D9851 llvm-svn: 237768
* PR23373: A defaulted union copy constructor that is not trivial must still beRichard Smith2015-04-291-1/+2
| | | | | | emitted as a memcpy. llvm-svn: 236142
* InstrProf: Stop using RegionCounter outside of CodeGenPGO (NFC)Justin Bogner2015-04-231-3/+3
| | | | | | | | | The RegionCounter type does a lot of legwork, but most of it is only meaningful within the implementation of CodeGenPGO. The uses elsewhere in CodeGen generally just want to increment or read counters, so do that directly. llvm-svn: 235664
* clang-format my last commitDavid Blaikie2015-04-051-1/+1
| | | | | | (sorry, keep forgetting that) llvm-svn: 234129
* [opaque pointer type] More GEP API migrationsDavid Blaikie2015-04-051-2/+2
| | | | | | | Looks like the VTable code in particular will need some work to pass around the pointee type explicitly. llvm-svn: 234128
* Sema: Parenthesized bound destructor member expressions can be calledDavid Majnemer2015-02-251-1/+1
| | | | | | | | | We would wrongfully reject (a.~A)() in both the destructor and pseudo-destructor cases. This fixes PR22668. llvm-svn: 230512
* Revert "Revert r229082 for a bit, it caused PR22577."David Majnemer2015-02-141-3/+5
| | | | | | | This reverts commit r229123. It was a red herring, the bug was present without r229082. llvm-svn: 229205
* Revert r229082 for a bit, it caused PR22577.Nico Weber2015-02-131-5/+3
| | | | llvm-svn: 229123
* MS ABI: Implement /volatile:msDavid Majnemer2015-02-131-3/+5
| | | | | | | | | | | | The /volatile:ms semantics turn volatile loads and stores into atomic acquire and release operations. This distinction is important because volatile memory operations do not form a happens-before relationship with non-atomic memory. This means that a volatile store is not sufficient for implementing a mutex unlock routine. Differential Revision: http://reviews.llvm.org/D7580 llvm-svn: 229082
* DebugInfo: Refactor default arg handling into a common place (instead of ↵David Blaikie2015-02-091-5/+0
| | | | | | handling in repeatedly for aggregate, complex, and scalar types) llvm-svn: 228591
* DebugInfo: Suppress the location of instructions in aggregate default arguments.David Blaikie2015-02-091-0/+5
| | | | | | | | Matches the existing code for scalar default arguments. Complex default arguments probably need the same handling too (test/fix to that coming next). llvm-svn: 228588
* DebugInfo: Use the preferred location rather than the start location for ↵David Blaikie2015-01-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | expression line info This causes things like assignment to refer to the '=' rather than the LHS when attributing the store instruction, for example. There were essentially 3 options for this: * The beginning of an expression (this was the behavior prior to this commit). This meant that stepping through subexpressions would bounce around from subexpressions back to the start of the outer expression, etc. (eg: x + y + z would go x, y, x, z, x (the repeated 'x's would be where the actual addition occurred)). * The end of an expression. This seems to be what GCC does /mostly/, and certainly this for function calls. This has the advantage that progress is always 'forwards' (never jumping backwards - except for independent subexpressions if they're evaluated in interesting orders, etc). "x + y + z" would go "x y z" with the additions occurring at y and z after the respective loads. The problem with this is that the user would still have to think fairly hard about precedence to realize which subexpression is being evaluated or which operator overload is being called in, say, an asan backtrace. * The preferred location or 'exprloc'. In this case you get sort of what you'd expect, though it's a bit confusing in its own way due to going 'backwards'. In this case the locations would be: "x y + z +" in lovely postfix arithmetic order. But this does mean that if the op+ were an operator overload, say, and in a backtrace, the backtrace will point to the exact '+' that's being called, not to the end of one of its operands. (actually the operator overload case doesn't work yet for other reasons, but that's being fixed - but this at least gets scalar/complex assignments and other plain operators right) llvm-svn: 227027
* DebugInfo: Attribute aggregate expressions to the source location of the ↵David Blaikie2015-01-181-0/+5
| | | | | | | | | expression Just as r225956 did for scalar expressions (CGExprScalar::Visit), do the same for aggregate expressions. llvm-svn: 226388
* PR18097: Support initializing an _Atomic(T) from an object of C++ class type TRichard Smith2014-07-311-0/+10
| | | | | | | or a class derived from T. We already supported this when initializing _Atomic(T) from T for most (and maybe all) other reasonable values of T. llvm-svn: 214390
* A non-trivial array-fill expression isn't necessarily a CXXConstructExpr. ItRichard Smith2014-06-131-6/+24
| | | | | | | could be an InitListExpr that runs constructors in C++11 onwards. Fixes a recent regression (introduced in r210091). llvm-svn: 210954
* Remove incorrect assertion.Richard Smith2014-06-031-4/+3
| | | | llvm-svn: 210092
* [C++11] Use 'nullptr'. CodeGen edition.Craig Topper2014-05-211-10/+11
| | | | llvm-svn: 209272
* [C++11] Replacing RecordDecl iterators field_begin() and field_end() with ↵Aaron Ballman2014-03-081-9/+4
| | | | | | iterator_range fields(). Updating all of the usages of the iterators with range-based for loops. llvm-svn: 203355
* Change PGO instrumentation to compute counts in a separate AST traversal.Bob Wilson2014-02-171-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, we made one traversal of the AST prior to codegen to assign counters to the ASTs and then propagated the count values during codegen. This patch now adds a separate AST traversal prior to codegen for the -fprofile-instr-use option to propagate the count values. The counts are then saved in a map from which they can be retrieved during codegen. This new approach has several advantages: 1. It gets rid of a lot of extra PGO-related code that had previously been added to codegen. 2. It fixes a serious bug. My original implementation (which was mailed to the list but never committed) used 3 counters for every loop. Justin improved it to move 2 of those counters into the less-frequently executed breaks and continues, but that turned out to produce wrong count values in some cases. The solution requires visiting a loop body before the condition so that the count for the condition properly includes the break and continue counts. Changing codegen to visit a loop body first would be a fairly invasive change, but with a separate AST traversal, it is easy to control the order of traversal. I've added a testcase (provided by Justin) to make sure this works correctly. 3. It improves the instrumentation overhead, reducing the number of counters for a loop from 3 to 1. We no longer need dedicated counters for breaks and continues, since we can just use the propagated count values when visiting breaks and continues. To make this work, I needed to make a change to the way we count case statements, going back to my original approach of not including the fall-through in the counter values. This was necessary because there isn't always an AST node that can be used to record the fall-through count. Now case statements are handled the same as default statements, with the fall-through paths branching over the counter increments. While I was at it, I also went back to using this approach for do-loops -- omitting the fall-through count into the loop body simplifies some of the calculations and make them behave the same as other loops. Whenever we start using this instrumentation for coverage, we'll need to add the fall-through counts into the counter values. llvm-svn: 201528
* Handle va_arg on struct types for the le32 target (PNaCl and Emscripten)Mark Seaborn2014-01-221-1/+5
| | | | | | | | | | | | | | | PNaCl and Emscripten can both handle va_arg IR instructions with struct type. Also add a test to cover generating a va_arg IR instruction from va_arg in C on le32 (as already handled by VisitVAArgExpr() in CGExprScalar.cpp), which was not covered by a test before. (This fixes https://code.google.com/p/nativeclient/issues/detail?id=2381) Differential Revision: http://llvm-reviews.chandlerc.com/D2539 llvm-svn: 199830
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