[llvm] 9a23e67 - [OpenMP][NFC] Expose AAExecutionDomain and rename its getter

[Johannes Doerfert via llvm-commits]

Author: Johannes Doerfert
Date: 2021-06-18T01:07:52-05:00
New Revision: 9a23e673caebdd54d8cc285fcad78f18fa2e919a

URL: https://github.com/llvm/llvm-project/commit/9a23e673caebdd54d8cc285fcad78f18fa2e919a
DIFF: https://github.com/llvm/llvm-project/commit/9a23e673caebdd54d8cc285fcad78f18fa2e919a.diff

LOG: [OpenMP][NFC] Expose AAExecutionDomain and rename its getter

The initial use for AAExecutionDomain was to determine if a single
thread executes a block. While this is sometimes informative most
of the time, and for other reasons, we actually want to know if it
is the "initial thread". Thus, the thread that started execution on
the current device. The deduction needs to be adjusted in a follow
up as the methods we use right not are looking for the OpenMP thread
id which is resets whenever a thread enters a parallel region. What
we basically want is to look for `llvm.nvvm.read.ptx.sreg.ntid.x` and
equivalent functions.

Added: 
    

Modified: 
    llvm/include/llvm/Transforms/IPO/Attributor.h
    llvm/lib/Transforms/IPO/OpenMPOpt.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Transforms/IPO/Attributor.h b/llvm/include/llvm/Transforms/IPO/Attributor.h
index 4a0c921f6fbf..0f26e136c587 100644
--- a/llvm/include/llvm/Transforms/IPO/Attributor.h
+++ b/llvm/include/llvm/Transforms/IPO/Attributor.h
@@ -4018,6 +4018,37 @@ struct DOTGraphTraits<AttributorCallGraph *> : public DefaultDOTGraphTraits {
   }
 };
 
+struct AAExecutionDomain
+    : public StateWrapper<BooleanState, AbstractAttribute> {
+  using Base = StateWrapper<BooleanState, AbstractAttribute>;
+  AAExecutionDomain(const IRPosition &IRP, Attributor &A) : Base(IRP) {}
+
+  /// Create an abstract attribute view for the position \p IRP.
+  static AAExecutionDomain &createForPosition(const IRPosition &IRP,
+                                              Attributor &A);
+
+  /// See AbstractAttribute::getName().
+  const std::string getName() const override { return "AAExecutionDomain"; }
+
+  /// See AbstractAttribute::getIdAddr().
+  const char *getIdAddr() const override { return &ID; }
+
+  /// Check if an instruction is executed only by the initial thread.
+  virtual bool isExecutedByInitialThreadOnly(const Instruction &) const = 0;
+
+  /// Check if a basic block is executed only by the initial thread.
+  virtual bool isExecutedByInitialThreadOnly(const BasicBlock &) const = 0;
+
+  /// This function should return true if the type of the \p AA is
+  /// AAExecutionDomain.
+  static bool classof(const AbstractAttribute *AA) {
+    return (AA->getIdAddr() == &ID);
+  }
+
+  /// Unique ID (due to the unique address)
+  static const char ID;
+};
+
 /// Run options, used by the pass manager.
 enum AttributorRunOption {
   NONE = 0,

diff  --git a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
index 87440d7557f0..d548f9afb7ee 100644
--- a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
+++ b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
@@ -82,36 +82,6 @@ static constexpr auto TAG = "[" DEBUG_TYPE "]";
 
 namespace {
 
-struct AAExecutionDomain
-    : public StateWrapper<BooleanState, AbstractAttribute> {
-  using Base = StateWrapper<BooleanState, AbstractAttribute>;
-  AAExecutionDomain(const IRPosition &IRP, Attributor &A) : Base(IRP) {}
-
-  /// Create an abstract attribute view for the position \p IRP.
-  static AAExecutionDomain &createForPosition(const IRPosition &IRP,
-                                              Attributor &A);
-
-  /// See AbstractAttribute::getName().
-  const std::string getName() const override { return "AAExecutionDomain"; }
-
-  /// See AbstractAttribute::getIdAddr().
-  const char *getIdAddr() const override { return &ID; }
-
-  /// Check if an instruction is executed by a single thread.
-  virtual bool isSingleThreadExecution(const Instruction &) const = 0;
-
-  virtual bool isSingleThreadExecution(const BasicBlock &) const = 0;
-
-  /// This function should return true if the type of the \p AA is
-  /// AAExecutionDomain.
-  static bool classof(const AbstractAttribute *AA) {
-    return (AA->getIdAddr() == &ID);
-  }
-
-  /// Unique ID (due to the unique address)
-  static const char ID;
-};
-
 struct AAICVTracker;
 
 /// OpenMP specific information. For now, stores RFIs and ICVs also needed for
@@ -2314,11 +2284,11 @@ struct AAExecutionDomainFunction : public AAExecutionDomain {
   ChangeStatus updateImpl(Attributor &A) override;
 
   /// Check if an instruction is executed by a single thread.
-  bool isSingleThreadExecution(const Instruction &I) const override {
-    return isSingleThreadExecution(*I.getParent());
+  bool isExecutedByInitialThreadOnly(const Instruction &I) const override {
+    return isExecutedByInitialThreadOnly(*I.getParent());
   }
 
-  bool isSingleThreadExecution(const BasicBlock &BB) const override {
+  bool isExecutedByInitialThreadOnly(const BasicBlock &BB) const override {
     return SingleThreadedBBs.contains(&BB);
   }
 
@@ -2339,7 +2309,8 @@ ChangeStatus AAExecutionDomainFunction::updateImpl(Attributor &A) {
     const auto &ExecutionDomainAA = A.getAAFor<AAExecutionDomain>(
         *this, IRPosition::function(*ACS.getInstruction()->getFunction()),
         DepClassTy::REQUIRED);
-    return ExecutionDomainAA.isSingleThreadExecution(*ACS.getInstruction());
+    return ExecutionDomainAA.isExecutedByInitialThreadOnly(
+        *ACS.getInstruction());
   };
 
   if (!A.checkForAllCallSites(PredForCallSite, *this,