Move SIMD alignment calculation to LLVM Frontend

Currently default simd alignment is defined by Clang specific TargetInfo class.
This class cannot be reused for LLVM Flang. That's why default simd alignment
calculation has been moved to OMPIRBuilder which is common for Flang and Clang.

Previous attempt: https://reviews.llvm.org/D138496 was wrong because
the default alignment depended on the number of built LLVM targets.

If we wanted to calculate the default alignment for PPC and we hadn't specified
PPC LLVM target to build, then we would get 0 as the alignment because
OMPIRBuilder couldn't create PPCTargetMachine object and it returned 0 as
the default value.

If PPC LLVM target had been built earlier, then OMPIRBuilder could have created
PPCTargetMachine object and it would have returned 128.

Differential Revision: https://reviews.llvm.org/D141910

Reviewed By: jdoerfert

clang/include/clang/Basic/TargetInfo.h

@@ -225,7 +225,6 @@ class TargetInfo : public virtual TransferrableTargetInfo,
   bool HasStrictFP;
 
   unsigned char MaxAtomicPromoteWidth, MaxAtomicInlineWidth;
-  unsigned short SimdDefaultAlign;
   std::string DataLayoutString;
   const char *UserLabelPrefix;
   const char *MCountName;
@@ -794,10 +793,6 @@ class TargetInfo : public virtual TransferrableTargetInfo,
 
   /// Return the maximum vector alignment supported for the given target.
   unsigned getMaxVectorAlign() const { return MaxVectorAlign; }
-  /// Return default simd alignment for the given target. Generally, this
-  /// value is type-specific, but this alignment can be used for most of the
-  /// types for the given target.
-  unsigned getSimdDefaultAlign() const { return SimdDefaultAlign; }
 
   unsigned getMaxOpenCLWorkGroupSize() const { return MaxOpenCLWorkGroupSize; }
 

clang/lib/AST/ASTContext.cpp

@@ -77,6 +77,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
 #include "llvm/Support/Capacity.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/Compiler.h"
@@ -2539,7 +2540,8 @@ unsigned ASTContext::getTypeUnadjustedAlign(const Type *T) const {
 }
 
 unsigned ASTContext::getOpenMPDefaultSimdAlign(QualType T) const {
-  unsigned SimdAlign = getTargetInfo().getSimdDefaultAlign();
+  unsigned SimdAlign = llvm::OpenMPIRBuilder::getOpenMPDefaultSimdAlign(
+      getTargetInfo().getTriple(), Target->getTargetOpts().FeatureMap);
   return SimdAlign;
 }
 

clang/lib/AST/CMakeLists.txt

@@ -132,4 +132,5 @@ add_clang_library(clangAST
   ClangAttrDocTable
   Opcodes
   omp_gen
+  intrinsics_gen
   )

clang/lib/Basic/TargetInfo.cpp

@@ -119,7 +119,6 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : Triple(T) {
   MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 0;
   MaxVectorAlign = 0;
   MaxTLSAlign = 0;
-  SimdDefaultAlign = 0;
   SizeType = UnsignedLong;
   PtrDiffType = SignedLong;
   IntMaxType = SignedLongLong;

clang/lib/Basic/Targets/PPC.h

@@ -87,7 +87,6 @@ class LLVM_LIBRARY_VISIBILITY PPCTargetInfo : public TargetInfo {
   PPCTargetInfo(const llvm::Triple &Triple, const TargetOptions &)
       : TargetInfo(Triple) {
     SuitableAlign = 128;
-    SimdDefaultAlign = 128;
     LongDoubleWidth = LongDoubleAlign = 128;
     LongDoubleFormat = &llvm::APFloat::PPCDoubleDouble();
     HasStrictFP = true;

clang/lib/Basic/Targets/WebAssembly.h

@@ -49,7 +49,6 @@ class LLVM_LIBRARY_VISIBILITY WebAssemblyTargetInfo : public TargetInfo {
     SuitableAlign = 128;
     LargeArrayMinWidth = 128;
     LargeArrayAlign = 128;
-    SimdDefaultAlign = 128;
     SigAtomicType = SignedLong;
     LongDoubleWidth = LongDoubleAlign = 128;
     LongDoubleFormat = &llvm::APFloat::IEEEquad();

clang/lib/Basic/Targets/X86.cpp

@@ -400,9 +400,6 @@ bool X86TargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
     return false;
   }
 
-  SimdDefaultAlign =
-      hasFeature("avx512f") ? 512 : hasFeature("avx") ? 256 : 128;
-
   // FIXME: We should allow long double type on 32-bits to match with GCC.
   // This requires backend to be able to lower f80 without x87 first.
   if (!HasX87 && LongDoubleFormat == &llvm::APFloat::x87DoubleExtended())

lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp

@@ -500,8 +500,6 @@ ClangExpressionParser::ClangExpressionParser(
   auto target_info = TargetInfo::CreateTargetInfo(
       m_compiler->getDiagnostics(), m_compiler->getInvocation().TargetOpts);
   if (log) {
-    LLDB_LOGF(log, "Using SIMD alignment: %d",
-              target_info->getSimdDefaultAlign());
     LLDB_LOGF(log, "Target datalayout string: '%s'",
               target_info->getDataLayoutString());
     LLDB_LOGF(log, "Target ABI: '%s'", target_info->getABI().str().c_str());

llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h

@@ -502,6 +502,13 @@ class OpenMPIRBuilder {
                                    ArrayRef<CanonicalLoopInfo *> Loops,
                                    InsertPointTy ComputeIP);
 
+  /// Get the default alignment value for given target
+  ///
+  /// \param TargetTriple   Target triple
+  /// \param Features       StringMap which describes extra CPU features
+  static unsigned getOpenMPDefaultSimdAlign(const Triple &TargetTriple,
+                                            const StringMap<bool> &Features);
+
 private:
   /// Modifies the canonical loop to be a statically-scheduled workshare loop.
   ///

llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp

@@ -3053,6 +3053,23 @@ void OpenMPIRBuilder::createIfVersion(CanonicalLoopInfo *CanonicalLoop,
   Builder.CreateBr(NewBlocks.front());
 }
 
+unsigned
+OpenMPIRBuilder::getOpenMPDefaultSimdAlign(const Triple &TargetTriple,
+                                           const StringMap<bool> &Features) {
+  if (TargetTriple.isX86()) {
+    if (Features.lookup("avx512f"))
+      return 512;
+    else if (Features.lookup("avx"))
+      return 256;
+    return 128;
+  }
+  if (TargetTriple.isPPC())
+    return 128;
+  if (TargetTriple.isWasm())
+    return 128;
+  return 0;
+}
+
 void OpenMPIRBuilder::applySimd(CanonicalLoopInfo *CanonicalLoop,
                                 MapVector<Value *, Value *> AlignedVars,
                                 Value *IfCond, OrderKind Order,