[cfe-commits] r105589 - in /cfe/trunk/lib: CodeGen/CGExprScalar.cpp Sema/SemaChecking.cpp

Nate Begeman natebegeman at mac.com
Mon Jun 7 17:16:34 PDT 2010


Author: sampo
Date: Mon Jun  7 19:16:34 2010
New Revision: 105589

URL: http://llvm.org/viewvc/llvm-project?rev=105589&view=rev
Log:
Extend __builtin_shufflevector to expose the full power of the llvm shufflevector instruction.  This means it can now be used for vector truncation and concatenation.  This will be used for the ARM NEON implementation.

Modified:
    cfe/trunk/lib/CodeGen/CGExprScalar.cpp
    cfe/trunk/lib/Sema/SemaChecking.cpp

Modified: cfe/trunk/lib/CodeGen/CGExprScalar.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExprScalar.cpp?rev=105589&r1=105588&r2=105589&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGExprScalar.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGExprScalar.cpp Mon Jun  7 19:16:34 2010
@@ -578,12 +578,104 @@
 }
 
 Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
-  llvm::SmallVector<llvm::Constant*, 32> indices;
-  for (unsigned i = 2; i < E->getNumSubExprs(); i++) {
-    indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i))));
+  // Vector Mask Case
+  if (E->getNumSubExprs() == 2 || 
+      E->getNumSubExprs() == 3 && E->getExpr(2)->getType()->isVectorType()) {
+    Value* LHS = CGF.EmitScalarExpr(E->getExpr(0));
+    Value* RHS = CGF.EmitScalarExpr(E->getExpr(1));
+    Value* Mask;
+    
+    const llvm::Type *I32Ty = llvm::Type::getInt32Ty(CGF.getLLVMContext());
+    const llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType());
+    unsigned LHSElts = LTy->getNumElements();
+
+    if (E->getNumSubExprs() == 3) {
+      Mask = CGF.EmitScalarExpr(E->getExpr(2));
+      
+      // Shuffle LHS & RHS into one input vector.
+      llvm::SmallVector<llvm::Constant*, 32> concat;
+      for (unsigned i = 0; i != LHSElts; ++i) {
+        concat.push_back(llvm::ConstantInt::get(I32Ty, 2*i));
+        concat.push_back(llvm::ConstantInt::get(I32Ty, 2*i+1));
+      }
+      
+      Value* CV = llvm::ConstantVector::get(concat.begin(), concat.size());
+      LHS = Builder.CreateShuffleVector(LHS, RHS, CV, "concat");
+      LHSElts *= 2;
+    } else {
+      Mask = RHS;
+    }
+    
+    const llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType());
+    llvm::Constant* EltMask;
+    
+    // Treat vec3 like vec4.
+    if ((LHSElts == 6) && (E->getNumSubExprs() == 3))
+      EltMask = llvm::ConstantInt::get(MTy->getElementType(),
+                                       (1 << llvm::Log2_32(LHSElts+2))-1);
+    else if ((LHSElts == 3) && (E->getNumSubExprs() == 2))
+      EltMask = llvm::ConstantInt::get(MTy->getElementType(),
+                                       (1 << llvm::Log2_32(LHSElts+1))-1);
+    else
+      EltMask = llvm::ConstantInt::get(MTy->getElementType(),
+                                       (1 << llvm::Log2_32(LHSElts))-1);
+             
+    // Mask off the high bits of each shuffle index.
+    llvm::SmallVector<llvm::Constant *, 32> MaskV;
+    for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i)
+      MaskV.push_back(EltMask);
+    
+    Value* MaskBits = llvm::ConstantVector::get(MaskV.begin(), MaskV.size());
+    Mask = Builder.CreateAnd(Mask, MaskBits, "mask");
+    
+    // newv = undef
+    // mask = mask & maskbits
+    // for each elt
+    //   n = extract mask i
+    //   x = extract val n
+    //   newv = insert newv, x, i
+    const llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(),
+                                                        MTy->getNumElements());
+    Value* NewV = llvm::UndefValue::get(RTy);
+    for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) {
+      Value *Indx = llvm::ConstantInt::get(I32Ty, i);
+      Indx = Builder.CreateExtractElement(Mask, Indx, "shuf_idx");
+      Indx = Builder.CreateZExt(Indx, I32Ty, "idx_zext");
+      
+      // Handle vec3 special since the index will be off by one for the RHS.
+      if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) {
+        Value *cmpIndx, *newIndx;
+        cmpIndx = Builder.CreateICmpUGT(Indx, llvm::ConstantInt::get(I32Ty, 3),
+                                        "cmp_shuf_idx");
+        newIndx = Builder.CreateSub(Indx, llvm::ConstantInt::get(I32Ty, 1),
+                                    "shuf_idx_adj");
+        Indx = Builder.CreateSelect(cmpIndx, newIndx, Indx, "sel_shuf_idx");
+      }
+      Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt");
+      NewV = Builder.CreateInsertElement(NewV, VExt, Indx, "shuf_ins");
+    }
+    return NewV;
   }
+  
   Value* V1 = CGF.EmitScalarExpr(E->getExpr(0));
   Value* V2 = CGF.EmitScalarExpr(E->getExpr(1));
+  
+  // Handle vec3 special since the index will be off by one for the RHS.
+  llvm::SmallVector<llvm::Constant*, 32> indices;
+  for (unsigned i = 2; i < E->getNumSubExprs(); i++) {
+    llvm::Constant *C = cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)));
+    const llvm::VectorType *VTy = cast<llvm::VectorType>(V1->getType());
+    if (VTy->getNumElements() == 3) {
+      if (llvm::ConstantInt *CI = dyn_cast<llvm::ConstantInt>(C)) {
+        uint64_t cVal = CI->getZExtValue();
+        if (cVal > 3) {
+          C = llvm::ConstantInt::get(C->getType(), cVal-1);
+        }
+      }
+    }
+    indices.push_back(C);
+  }
+
   Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size());
   return Builder.CreateShuffleVector(V1, V2, SV, "shuffle");
 }

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=105589&r1=105588&r2=105589&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Mon Jun  7 19:16:34 2010
@@ -633,45 +633,53 @@
 /// SemaBuiltinShuffleVector - Handle __builtin_shufflevector.
 // This is declared to take (...), so we have to check everything.
 Action::OwningExprResult Sema::SemaBuiltinShuffleVector(CallExpr *TheCall) {
-  if (TheCall->getNumArgs() < 3)
+  if (TheCall->getNumArgs() < 2)
     return ExprError(Diag(TheCall->getLocEnd(),
                           diag::err_typecheck_call_too_few_args_at_least)
-      << 0 /*function call*/ << 3 << TheCall->getNumArgs()
+      << 0 /*function call*/ << 2 << TheCall->getNumArgs()
       << TheCall->getSourceRange());
 
-  unsigned numElements = std::numeric_limits<unsigned>::max();
+  // Determine which of the following types of shufflevector we're checking:
+  // 1) unary, vector mask: (lhs, mask)
+  // 2) binary, vector mask: (lhs, rhs, mask)
+  // 3) binary, scalar mask: (lhs, rhs, index, ..., index)
+  QualType resType = TheCall->getArg(0)->getType();
+  unsigned numElements = 0;
+  
   if (!TheCall->getArg(0)->isTypeDependent() &&
       !TheCall->getArg(1)->isTypeDependent()) {
-    QualType FAType = TheCall->getArg(0)->getType();
-    QualType SAType = TheCall->getArg(1)->getType();
-
-    if (!FAType->isVectorType() || !SAType->isVectorType()) {
+    QualType LHSType = TheCall->getArg(0)->getType();
+    QualType RHSType = TheCall->getArg(1)->getType();
+    
+    if (!LHSType->isVectorType() || !RHSType->isVectorType()) {
       Diag(TheCall->getLocStart(), diag::err_shufflevector_non_vector)
         << SourceRange(TheCall->getArg(0)->getLocStart(),
                        TheCall->getArg(1)->getLocEnd());
       return ExprError();
     }
+    
+    numElements = LHSType->getAs<VectorType>()->getNumElements();
+    unsigned numResElements = TheCall->getNumArgs() - 2;
 
-    if (!Context.hasSameUnqualifiedType(FAType, SAType)) {
+    // Check to see if we have a call with 2 vector arguments, the unary shuffle
+    // with mask.  If so, verify that RHS is an integer vector type with the
+    // same number of elts as lhs.
+    if (TheCall->getNumArgs() == 2) {
+      if (!RHSType->isIntegerType() || 
+          RHSType->getAs<VectorType>()->getNumElements() != numElements)
+        Diag(TheCall->getLocStart(), diag::err_shufflevector_incompatible_vector)
+          << SourceRange(TheCall->getArg(1)->getLocStart(),
+                         TheCall->getArg(1)->getLocEnd());
+      numResElements = numElements;
+    }
+    else if (!Context.hasSameUnqualifiedType(LHSType, RHSType)) {
       Diag(TheCall->getLocStart(), diag::err_shufflevector_incompatible_vector)
         << SourceRange(TheCall->getArg(0)->getLocStart(),
                        TheCall->getArg(1)->getLocEnd());
       return ExprError();
-    }
-
-    numElements = FAType->getAs<VectorType>()->getNumElements();
-    if (TheCall->getNumArgs() != numElements+2) {
-      if (TheCall->getNumArgs() < numElements+2)
-        return ExprError(Diag(TheCall->getLocEnd(),
-                              diag::err_typecheck_call_too_few_args)
-                 << 0 /*function call*/ 
-                 << numElements+2 << TheCall->getNumArgs()
-                 << TheCall->getSourceRange());
-      return ExprError(Diag(TheCall->getLocEnd(),
-                            diag::err_typecheck_call_too_many_args)
-                 << 0 /*function call*/ 
-                 << numElements+2 << TheCall->getNumArgs()
-                 << TheCall->getSourceRange());
+    } else if (numElements != numResElements) {
+      QualType eltType = LHSType->getAs<VectorType>()->getElementType();
+      resType = Context.getVectorType(eltType, numResElements, false, false);
     }
   }
 
@@ -680,9 +688,11 @@
         TheCall->getArg(i)->isValueDependent())
       continue;
 
-    llvm::APSInt Result;
-    if (SemaBuiltinConstantArg(TheCall, i, Result))
-      return ExprError();
+    llvm::APSInt Result(32);
+    if (!TheCall->getArg(i)->isIntegerConstantExpr(Result, Context))
+      return ExprError(Diag(TheCall->getLocStart(),
+                  diag::err_shufflevector_nonconstant_argument)
+                << TheCall->getArg(i)->getSourceRange());
 
     if (Result.getActiveBits() > 64 || Result.getZExtValue() >= numElements*2)
       return ExprError(Diag(TheCall->getLocStart(),
@@ -698,7 +708,7 @@
   }
 
   return Owned(new (Context) ShuffleVectorExpr(Context, exprs.begin(),
-                                            exprs.size(), exprs[0]->getType(),
+                                            exprs.size(), resType,
                                             TheCall->getCallee()->getLocStart(),
                                             TheCall->getRParenLoc()));
 }





More information about the cfe-commits mailing list