refine the code style (apache#10112)

Author: yangulei

include/tvm/tir/op.h

@@ -862,18 +862,18 @@ TVM_DLL PrimExpr q_multiply_shift(PrimExpr x, PrimExpr y, PrimExpr q, PrimExpr s
                                   Span span = Span());
 
 // Intrinsic operators
-#define TVM_DECLARE_INTRIN_UNARY(OpName)                       \
-  inline PrimExpr OpName(PrimExpr x, Span span = Span()) {     \
-    static const Op& op = Op::Get("tir." #OpName);             \
-    if (x.dtype().is_bfloat16()) {                             \
-      DataType srcType = x.dtype();                            \
-      DataType dstType(kDLFloat, 32, srcType.lanes());         \
-      PrimExpr castX = tir::Cast(dstType, {x}, span);          \
-      PrimExpr result = tir::Call(dstType, op, {castX}, span); \
-      return tir::Cast(srcType, {result}, span);               \
-    } else {                                                   \
-      return tir::Call(x.dtype(), op, {x}, span);              \
-    }                                                          \
+#define TVM_DECLARE_INTRIN_UNARY(OpName)                                \
+  inline PrimExpr OpName(PrimExpr x, Span span = Span()) {              \
+    static const Op& op = Op::Get("tir." #OpName);                      \
+    if (x.dtype().is_bfloat16()) {                                      \
+      DataType bf16_dtype = x.dtype();                                  \
+      DataType fp32_dtype(kDLFloat, 32, bf16_dtype.lanes());            \
+      PrimExpr x_fp32 = tir::Cast(fp32_dtype, {x}, span);               \
+      PrimExpr result_fp32 = tir::Call(fp32_dtype, op, {x_fp32}, span); \
+      return tir::Cast(bf16_dtype, {result_fp32}, span);                \
+    } else {                                                            \
+      return tir::Call(x.dtype(), op, {x}, span);                       \
+    }                                                                   \
   }
 
 TVM_DECLARE_INTRIN_UNARY(exp);