commit 37b6a5731a47f811d754f0d48aa93edf30e30513
author Nate Begeman <natebegeman@mac.com> Tue Jun 08 00:16:34 2010 +0000
committer Nate Begeman <natebegeman@mac.com> Tue Jun 08 00:16:34 2010 +0000
tree 4959c0b61c17185833fa40a19a6e7bfdeeb9a824
parent 6c6424bc0d3b5f080a97b5f6ef4a8d70c38e38f5

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.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@105589 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaChecking.cpp

diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index d47f2ce..7fa5762 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -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()));
 }