[Clang][RISCV] bfloat uses 'y' instead of 'b' (#76575)

Builtins.def says that bfloat should be represented by the 'y' character, not the 'b' character. The 'b' character is specified to represent boolean. The implementation currently uses 'b' correctly for boolean and incorrectly re-uses 'b' for bfloat. This was not caught since no builtins are emitted in build/tools/clang/include/clang/Basic/riscv_sifive_vector_builtins.inc. Don't know that we can test this without creating builtins that expose this issue, although I'm not sure we really want to do that.
llvm · Dec 30, 2023 · fa8347f · fa8347f
1 parent 81cedac
commit fa8347f
Show file tree

Hide file tree

Showing 4 changed files with 4 additions and 4 deletions.
diff --git a/clang/include/clang/Basic/riscv_sifive_vector.td b/clang/include/clang/Basic/riscv_sifive_vector.td
@@ -109,7 +109,7 @@ multiclass RVVVFWMACCBuiltinSet<list<list<string>> suffixes_prototypes> {
       Name = NAME,
       HasMasked = false,
       Log2LMUL = [-2, -1, 0, 1, 2] in
-    defm NAME : RVVOutOp1Op2BuiltinSet<NAME, "b", suffixes_prototypes>;
+    defm NAME : RVVOutOp1Op2BuiltinSet<NAME, "y", suffixes_prototypes>;
 }
 
 multiclass RVVVQMACCDODBuiltinSet<list<list<string>> suffixes_prototypes> {

diff --git a/clang/include/clang/Basic/riscv_vector_common.td b/clang/include/clang/Basic/riscv_vector_common.td
@@ -41,7 +41,7 @@
 //   x: float16_t (half)
 //   f: float32_t (float)
 //   d: float64_t (double)
-//   b: bfloat16_t (bfloat16)
+//   y: bfloat16_t (bfloat16)
 //
 // This way, given an LMUL, a record with a TypeRange "sil" will cause the
 // definition of 3 builtins. Each type "t" in the TypeRange (in this example

diff --git a/clang/lib/Support/RISCVVIntrinsicUtils.cpp b/clang/lib/Support/RISCVVIntrinsicUtils.cpp
@@ -203,7 +203,7 @@ void RVVType::initBuiltinStr() {
     }
     break;
   case ScalarTypeKind::BFloat:
-    BuiltinStr += "b";
+    BuiltinStr += "y";
     break;
   default:
     llvm_unreachable("ScalarType is invalid!");

diff --git a/clang/utils/TableGen/RISCVVEmitter.cpp b/clang/utils/TableGen/RISCVVEmitter.cpp
@@ -151,7 +151,7 @@ static BasicType ParseBasicType(char c) {
   case 'd':
     return BasicType::Float64;
     break;
-  case 'b':
+  case 'y':
     return BasicType::BFloat16;
     break;
   default: