[Clang][RISCV] Use __builtin_popcount in __riscv_cpop_32/64 (#76286)

This patch replaces `__builtin_riscv_cpop_32/64` with `__builtin_popcount(ll)` because `__builtin_riscv_cpop_32/64` is not implemented in clang.

Author: dtcxzyw

clang/lib/Headers/riscv_bitmanip.h

@@ -34,7 +34,7 @@ __riscv_ctz_32(uint32_t __x) {
 
 static __inline__ unsigned __attribute__((__always_inline__, __nodebug__))
 __riscv_cpop_32(uint32_t __x) {
-  return __builtin_riscv_cpop_32(__x);
+  return __builtin_popcount(__x);
 }
 
 #if __riscv_xlen == 64
@@ -55,7 +55,7 @@ __riscv_ctz_64(uint64_t __x) {
 
 static __inline__ unsigned __attribute__((__always_inline__, __nodebug__))
 __riscv_cpop_64(uint64_t __x) {
-  return __builtin_riscv_cpop_64(__x);
+  return __builtin_popcountll(__x);
 }
 #endif
 #endif // defined(__riscv_zbb)

clang/test/CodeGen/RISCV/rvb-intrinsics/zbb.c

@@ -51,8 +51,8 @@ unsigned int clz_32(uint32_t a) {
 // RV64ZBB-LABEL: @clz_64(
 // RV64ZBB-NEXT:  entry:
 // RV64ZBB-NEXT:    [[TMP0:%.*]] = call i64 @llvm.ctlz.i64(i64 [[A:%.*]], i1 false)
-// RV64ZBB-NEXT:    [[CAST:%.*]] = trunc i64 [[TMP0]] to i32
-// RV64ZBB-NEXT:    ret i32 [[CAST]]
+// RV64ZBB-NEXT:    [[CAST_I:%.*]] = trunc i64 [[TMP0]] to i32
+// RV64ZBB-NEXT:    ret i32 [[CAST_I]]
 //
 unsigned int clz_64(uint64_t a) {
   return __riscv_clz_64(a);
@@ -77,10 +77,36 @@ unsigned int ctz_32(uint32_t a) {
 // RV64ZBB-LABEL: @ctz_64(
 // RV64ZBB-NEXT:  entry:
 // RV64ZBB-NEXT:    [[TMP0:%.*]] = call i64 @llvm.cttz.i64(i64 [[A:%.*]], i1 false)
-// RV64ZBB-NEXT:    [[CAST:%.*]] = trunc i64 [[TMP0]] to i32
-// RV64ZBB-NEXT:    ret i32 [[CAST]]
+// RV64ZBB-NEXT:    [[CAST_I:%.*]] = trunc i64 [[TMP0]] to i32
+// RV64ZBB-NEXT:    ret i32 [[CAST_I]]
 //
 unsigned int ctz_64(uint64_t a) {
   return __riscv_ctz_64(a);
 }
 #endif
+
+// RV32ZBB-LABEL: @cpop_32(
+// RV32ZBB-NEXT:  entry:
+// RV32ZBB-NEXT:    [[TMP0:%.*]] = call i32 @llvm.ctpop.i32(i32 [[A:%.*]])
+// RV32ZBB-NEXT:    ret i32 [[TMP0]]
+//
+// RV64ZBB-LABEL: @cpop_32(
+// RV64ZBB-NEXT:  entry:
+// RV64ZBB-NEXT:    [[TMP0:%.*]] = call i32 @llvm.ctpop.i32(i32 [[A:%.*]])
+// RV64ZBB-NEXT:    ret i32 [[TMP0]]
+//
+unsigned int cpop_32(uint32_t a) {
+  return __riscv_cpop_32(a);
+}
+
+#if __riscv_xlen == 64
+// RV64ZBB-LABEL: @cpop_64(
+// RV64ZBB-NEXT:  entry:
+// RV64ZBB-NEXT:    [[TMP0:%.*]] = call i64 @llvm.ctpop.i64(i64 [[A:%.*]])
+// RV64ZBB-NEXT:    [[CAST_I:%.*]] = trunc i64 [[TMP0]] to i32
+// RV64ZBB-NEXT:    ret i32 [[CAST_I]]
+//
+unsigned int cpop_64(uint64_t a) {
+  return __riscv_cpop_64(a);
+}
+#endif