[SVE] Remove usage of getMaxVScale for AArch64, in favour of IR Attribute

Removed AArch64 usage of the getMaxVScale interface, replacing it with
the vscale_range(min, max) IR Attribute.

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D106277

1 files changed, 7 insertions, 5 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index f5eed85..dca4204 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -484,11 +484,13 @@ void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
   //    function.
   CurFn->addFnAttr("min-legal-vector-width", llvm::utostr(LargestVectorWidth));
 
-  // Add vscale attribute if appropriate.
-  if (getLangOpts().ArmSveVectorBits) {
-    unsigned VScale = getLangOpts().ArmSveVectorBits / 128;
-    CurFn->addFnAttr(llvm::Attribute::getWithVScaleRangeArgs(getLLVMContext(),
-                                                             VScale, VScale));
+  // Add vscale_range attribute if appropriate.
+  Optional<std::pair<unsigned, unsigned>> VScaleRange =
+      getContext().getTargetInfo().getVScaleRange(getLangOpts());
+  if (VScaleRange) {
+    CurFn->addFnAttr(llvm::Attribute::getWithVScaleRangeArgs(
+        getLLVMContext(), VScaleRange.getValue().first,
+        VScaleRange.getValue().second));
   }
 
   // If we generated an unreachable return block, delete it now.