[clang] 89525cb - [Clang] Add helper method to determine if a nonvirtual base has an entry in the LLVM struct

[William S. Moses via cfe-commits]

Author: William S. Moses
Date: 2022-03-25T16:32:12-04:00
New Revision: 89525cbf283f1ffeca1e007a06b29917a9eadc53

URL: 
https://github.com/llvm/llvm-project/commit/89525cbf283f1ffeca1e007a06b29917a9eadc53
DIFF: 
https://github.com/llvm/llvm-project/commit/89525cbf283f1ffeca1e007a06b29917a9eadc53.diff

LOG: [Clang] Add helper method to determine if a nonvirtual base has an entry 
in the LLVM struct

This patch adds a helper method to determine if a nonvirtual base has an entry 
in the LLVM struct. Such a base may not have an entry
if the base does not have any fields/bases itself that would change the size of 
the struct. This utility method is useful for other frontends (Polygeist) that 
use Clang as an API to generate code.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D122502

Added: 


Modified: 
clang/lib/CodeGen/CGRecordLayout.h

Removed: 




diff  --git a/clang/lib/CodeGen/CGRecordLayout.h 
b/clang/lib/CodeGen/CGRecordLayout.h
index 5a3bcdf72f7b6..d5ea74922603b 100644
--- a/clang/lib/CodeGen/CGRecordLayout.h
+++ b/clang/lib/CodeGen/CGRecordLayout.h
@@ -200,6 +200,12 @@ class CGRecordLayout {
 return FieldInfo.lookup(FD);
   }
 
+  // Return whether the following non virtual base has a corresponding
+  // entry in the LLVM struct.
+  bool hasNonVirtualBaseLLVMField(const CXXRecordDecl *RD) const {
+return NonVirtualBases.count(RD);
+  }
+
   unsigned getNonVirtualBaseLLVMFieldNo(const CXXRecordDecl *RD) const {
 assert(NonVirtualBases.count(RD) && "Invalid non-virtual base!");
 return NonVirtualBases.lookup(RD);



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[clang] 87ec6f4 - [OpenMPIRBuilder] Allocate temporary at the correct block in a nested parallel

[William S. Moses via cfe-commits]

Author: William S. Moses
Date: 2022-03-06T18:34:25-05:00
New Revision: 87ec6f41bba6d72a3408e71cf19ae56feff523bc

URL: 
https://github.com/llvm/llvm-project/commit/87ec6f41bba6d72a3408e71cf19ae56feff523bc
DIFF: 
https://github.com/llvm/llvm-project/commit/87ec6f41bba6d72a3408e71cf19ae56feff523bc.diff

LOG: [OpenMPIRBuilder] Allocate temporary at the correct block in a nested 
parallel

The OpenMPIRBuilder has a bug. Specifically, suppose you have two nested openmp 
parallel regions (writing with MLIR for ease)

```
omp.parallel {
  %a = ...
  omp.parallel {
use(%a)
  }
}
```

As OpenMP only permits pointer-like inputs, the builder will wrap all of the 
inputs into a stack allocation, and then pass this
allocation to the inner parallel. For example, we would want to get something 
like the following:

```
omp.parallel {
  %a = ...
  %tmp = alloc
  store %tmp[] = %a
  kmpc_fork(outlined, %tmp)
}
```

However, in practice, this is not what currently occurs in the context of 
nested parallel regions. Specifically to the OpenMPIRBuilder,
the entirety of the function (at the LLVM level) is currently inlined with 
blocks marking the corresponding start and end of each
region.

```
entry:
  ...

parallel1:
  %a = ...
  ...

parallel2:
  use(%a)
  ...

endparallel2:
  ...

endparallel1:
  ...
```

When the allocation is inserted, it presently inserted into the parent of the 
entire function (e.g. entry) rather than the parent
allocation scope to the function being outlined. If we were outlining 
parallel2, the corresponding alloca location would be parallel1.

This causes a variety of bugs, including 
https://github.com/llvm/llvm-project/issues/54165 as one example.

This PR allows the stack allocation to be created at the correct allocation 
block, and thus remedies such issues.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D121061

Added: 
mlir/test/Target/LLVMIR/openmp-nested.mlir

Modified: 
clang/test/OpenMP/irbuilder_nested_openmp_parallel_empty.c
clang/test/OpenMP/irbuilder_nested_parallel_for.c
llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h
llvm/include/llvm/Transforms/Utils/CodeExtractor.h
llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
llvm/lib/Transforms/IPO/HotColdSplitting.cpp
llvm/lib/Transforms/IPO/IROutliner.cpp
llvm/lib/Transforms/Utils/CodeExtractor.cpp

Removed: 




diff  --git a/clang/test/OpenMP/irbuilder_nested_openmp_parallel_empty.c 
b/clang/test/OpenMP/irbuilder_nested_openmp_parallel_empty.c
index 56aa41b0db466..2c1139d7ef7df 100644
--- a/clang/test/OpenMP/irbuilder_nested_openmp_parallel_empty.c
+++ b/clang/test/OpenMP/irbuilder_nested_openmp_parallel_empty.c
@@ -33,8 +33,7 @@ void nested_parallel_0(void) {
 
 // ALL-LABEL: @_Z17nested_parallel_1Pfid(
 // ALL-NEXT:  entry:
-// ALL-NEXT:[[STRUCTARG14:%.*]] = alloca { { i32*, double*, float** }*, 
i32*, double*, float** }, align 8
-// ALL-NEXT:[[STRUCTARG:%.*]] = alloca { i32*, double*, float** }, align 8
+// ALL-NEXT:[[STRUCTARG14:%.*]] = alloca { i32*, double*, float** }, align 
8
 // ALL-NEXT:[[R_ADDR:%.*]] = alloca float*, align 8
 // ALL-NEXT:[[A_ADDR:%.*]] = alloca i32, align 4
 // ALL-NEXT:[[B_ADDR:%.*]] = alloca double, align 8
@@ -44,15 +43,13 @@ void nested_parallel_0(void) {
 // ALL-NEXT:[[OMP_GLOBAL_THREAD_NUM:%.*]] = call i32 
@__kmpc_global_thread_num(%struct.ident_t* @[[GLOB1]])
 // ALL-NEXT:br label [[OMP_PARALLEL:%.*]]
 // ALL:   omp_parallel:
-// ALL-NEXT:[[GEP_STRUCTARG:%.*]] = getelementptr { { i32*, double*, 
float** }*, i32*, double*, float** }, { { i32*, double*, float** }*, i32*, 
double*, float** }* [[STRUCTARG14]], i32 0, i32 0
-// ALL-NEXT:store { i32*, double*, float** }* [[STRUCTARG]], { i32*, 
double*, float** }** [[GEP_STRUCTARG]], align 8
-// ALL-NEXT:[[GEP_A_ADDR15:%.*]] = getelementptr { { i32*, double*, 
float** }*, i32*, double*, float** }, { { i32*, double*, float** }*, i32*, 
double*, float** }* [[STRUCTARG14]], i32 0, i32 1
+// ALL-NEXT:[[GEP_A_ADDR15:%.*]] = getelementptr { i32*, double*, float** 
}, { i32*, double*, float** }* [[STRUCTARG14]], i32 0, i32 0
 // ALL-NEXT:store i32* [[A_ADDR]], i32** [[GEP_A_ADDR15]], align 8
-// ALL-NEXT:[[GEP_B_ADDR16:%.*]] = getelementptr { { i32*, double*, 
float** }*, i32*, double*, float** }, { { i32*, double*, float** }*, i32*, 
double*, float** }* [[STRUCTARG14]], i32 0, i32 2
+// ALL-NEXT:[[GEP_B_ADDR16:%.*]] = getelementptr { i32*, double*, float** 
}, { i32*, double*, float** }* [[STRUCTARG14]], i32 0, i32 1
 // ALL-NEXT:store double* [[B_ADDR]], double** [[GEP_B_ADDR16]], align 8
-// ALL-NEXT:[[GEP_R_ADDR17:%.*]] = getelementptr { { i32*, double*, 
float** }*, i32*, double*, float** }, { { i32*, double*, float** }*, i32*, 
double*, float** }* [[STRUCTARG14]], i32 0, i32 3
+// ALL-NEXT:[[GEP_R_ADDR17:%.*]] = getelementptr { i32*, double*,