[llvm] 1e9924c - [LoongArch] Fixing the incorrect return value of LoongArchTTIImpl::getRegisterBitWidth (#79441)

[via llvm-commits]

Author: wanglei
Date: 2024-01-26T10:24:07+08:00
New Revision: 1e9924c1f248bbddcb95d82a59708d617297dad3

URL: https://github.com/llvm/llvm-project/commit/1e9924c1f248bbddcb95d82a59708d617297dad3
DIFF: https://github.com/llvm/llvm-project/commit/1e9924c1f248bbddcb95d82a59708d617297dad3.diff

LOG: [LoongArch] Fixing the incorrect return value of LoongArchTTIImpl::getRegisterBitWidth (#79441)

When we do not enable vector features, we should return the default
value (`TargetTransformInfoImplBase::getRegisterBitWidth`) instead of
zero.

This should fix the LoongArch [buildbot
breakage](https://lab.llvm.org/staging/#/builders/5/builds/486) from
#78943.

Added: 
    

Modified: 
    llvm/lib/Target/LoongArch/LoongArchTargetTransformInfo.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/LoongArch/LoongArchTargetTransformInfo.cpp b/llvm/lib/Target/LoongArch/LoongArchTargetTransformInfo.cpp
index 04349aa52b54089..d47dded9ea6ecf2 100644
--- a/llvm/lib/Target/LoongArch/LoongArchTargetTransformInfo.cpp
+++ b/llvm/lib/Target/LoongArch/LoongArchTargetTransformInfo.cpp
@@ -21,17 +21,20 @@ using namespace llvm;
 
 TypeSize LoongArchTTIImpl::getRegisterBitWidth(
     TargetTransformInfo::RegisterKind K) const {
+  TypeSize DefSize = TargetTransformInfoImplBase::getRegisterBitWidth(K);
   switch (K) {
   case TargetTransformInfo::RGK_Scalar:
     return TypeSize::getFixed(ST->is64Bit() ? 64 : 32);
   case TargetTransformInfo::RGK_FixedWidthVector:
-    if (ST->hasExtLASX() && ST->hasExpAutoVec())
+    if (!ST->hasExpAutoVec())
+      return DefSize;
+    if (ST->hasExtLASX())
       return TypeSize::getFixed(256);
-    if (ST->hasExtLSX() && ST->hasExpAutoVec())
+    if (ST->hasExtLSX())
       return TypeSize::getFixed(128);
-    return TypeSize::getFixed(0);
+    [[fallthrough]];
   case TargetTransformInfo::RGK_ScalableVector:
-    return TypeSize::getScalable(0);
+    return DefSize;
   }
 
   llvm_unreachable("Unsupported register kind");