[X86] scaleShuffleMask - avoid potential signed overflow warning.

Use size_t assignment to prevent a bad explicit type conversion warning.

Given the typical size of shuffle masks this was never going to happen, but this at least stops the warning.

Reported in https://www.viva64.com/en/b/0629/

llvm-svn: 359479

diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index 02f3417..eee8466 100644 (file)
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -1600,10 +1600,10 @@ namespace llvm {
   void scaleShuffleMask(int Scale, ArrayRef<T> Mask,
                         SmallVectorImpl<T> &ScaledMask) {
     assert(0 < Scale && "Unexpected scaling factor");
-    int NumElts = Mask.size();
-    ScaledMask.assign(static_cast<size_t>(NumElts * Scale), -1);
+    size_t NumElts = Mask.size();
+    ScaledMask.assign(NumElts * Scale, -1);
 
-    for (int i = 0; i != NumElts; ++i) {
+    for (int i = 0; i != (int)NumElts; ++i) {
       int M = Mask[i];
 
       // Repeat sentinel values in every mask element.