[SVE] fix IRMover returning wrong modified vector type

[nasherm]

Summary

Modified scalable vector types weren't correctly returned at link-time.
The previous behaviour was a FixedVectorType was constructed
when expecting a ScalableVectorType. This commit has added a regression
test which re-creates the failure as well as a fix.

[sdesmalen]

Hi @nasherm thanks for working on this fix.

llvm/lib/Linker/IRMover.cpp

300–303

These can both use the same interface to VectorType, e.g.:

case Type::ScalableVectorTyID:
case Type::FixedVectorTyID:
  return *Entry = VectorType::get(ElementTypes[0], cast<VectorType>(Ty)->getElementCount());

llvm/test/Linker/fixed-vector-type-construction.ll

1 ↗

(On Diff #324607)

I don't think this one needs a RUN line if you move this file to llvm/test/Linker/Inputs/

llvm/test/Linker/sve-type-construction.ll

1 ↗

(On Diff #324607)

Can you replace sve with scalable-vector (also in the filenames)? The test isn't necessarily specific to SVE.

1 ↗

(On Diff #324607)

This can use %s directly.

[nasherm]

Addressing Sander's comments.

[sdesmalen]

llvm/test/Linker/Inputs/fixed-vector-type-construction.ll

4

nit: please use 2 spaces.

llvm/test/Linker/scalable-vector-type-construction.ll

2

use %s directly (that expands to the same)

7

nit: please use 2 spaces.

[nasherm]

In response to Sander's comments.

• changed indentation of *.ll files to be in line with 2 space rule
• use %s interpolation in scalable-vector-type-construction.ll

[sdesmalen]

LGTM, thanks @nasherm!

llvm/lib/Linker/IRMover.cpp

#endif
 
   // Otherwise, rebuild a modified type.
   switch (Ty->getTypeID()) {
   default:
     llvm_unreachable("unknown derived type to remap");
   case Type::ArrayTyID:
     return *Entry = ArrayType::get(ElementTypes[0],
                                    cast<ArrayType>(Ty)->getNumElements());
   case Type::ScalableVectorTyID:
-    // FIXME: handle scalable vectors
   case Type::FixedVectorTyID:
-    return *Entry = FixedVectorType::get(
-               ElementTypes[0], cast<FixedVectorType>(Ty)->getNumElements());
+    return *Entry = VectorType::get(ElementTypes[0],
+                                    cast<VectorType>(Ty)->getElementCount());
   case Type::PointerTyID:
     return *Entry = PointerType::get(ElementTypes[0],
                                      cast<PointerType>(Ty)->getAddressSpace());
   case Type::FunctionTyID:
     return *Entry = FunctionType::get(ElementTypes[0],
                                       makeArrayRef(ElementTypes).slice(1),
                                       cast<FunctionType>(Ty)->isVarArg());
   case Type::StructTyID: {

llvm/test/Linker/Inputs/fixed-vector-type-construction.ll

+%t = type {i32, float}
+define void @foo(<4 x %t*> %x) {
+  ret void
+}

llvm/test/Linker/scalable-vector-type-construction.ll

+; RUN: llvm-link %p/Inputs/fixed-vector-type-construction.ll %s -S -o - | FileCheck %s
+%t = type {i32, float}
+; CHECK: define void @foo(<4 x
+; CHECK; define void @bar(<vscale x 4 x
+define void @bar(<vscale x 4 x %t*> %x) {
+  ret void
+}