[CIR][CIRGen][Builtin][Neon] Lower vshld_n_s64 and vshld_n_u64 (#1259)

Lowering `vshld_n_s64` and `vshld_n_u64`

Author: AmrDeveloper

clang/lib/CIR/CodeGen/CIRGenBuiltinAArch64.cpp

@@ -3820,7 +3820,10 @@ CIRGenFunction::emitAArch64BuiltinExpr(unsigned BuiltinID, const CallExpr *E,
   }
   case NEON::BI__builtin_neon_vshld_n_s64:
   case NEON::BI__builtin_neon_vshld_n_u64: {
-    llvm_unreachable("NEON::BI__builtin_neon_vshld_n_u64 NYI");
+    std::optional<llvm::APSInt> amt =
+        E->getArg(1)->getIntegerConstantExpr(getContext());
+    assert(amt && "Expected argument to be a constant");
+    return builder.createShiftLeft(Ops[0], amt->getZExtValue());
   }
   case NEON::BI__builtin_neon_vshrd_n_s64: {
     llvm_unreachable("NEON::BI__builtin_neon_vshrd_n_s64 NYI");

clang/test/CIR/CodeGen/AArch64/neon.c

@@ -15232,12 +15232,16 @@ uint64x1_t test_vrsra_n_u64(uint64x1_t a, uint64x1_t b) {
   // LLVM:   ret <1 x i64> [[TMP3]]
 }
 
-// NYI-LABEL: @test_vshld_n_s64(
-// NYI:   [[SHLD_N:%.*]] = shl i64 %a, 1
-// NYI:   ret i64 [[SHLD_N]]
-// int64_t test_vshld_n_s64(int64_t a) {
-//   return (int64_t)vshld_n_s64(a, 1);
-// }
+int64_t test_vshld_n_s64(int64_t a) {
+  return (int64_t)vshld_n_s64(a, 1);
+
+  // CIR-LABEL: vshld_n_s64
+  // CIR: {{%.*}} = cir.shift(left, {{%.*}} : !s64i, {{%.*}} : !s64i) -> !s64i
+
+  // LLVM-LABEL: @test_vshld_n_s64(
+  // LLVM:   [[SHLD_N:%.*]] = shl i64 %0, 1
+  // LLVM:   ret i64 [[SHLD_N]]
+}
 
 // NYI-LABEL: @test_vshl_n_s64(
 // NYI:   [[TMP0:%.*]] = bitcast <1 x i64> %a to <8 x i8>
@@ -15248,12 +15252,16 @@ uint64x1_t test_vrsra_n_u64(uint64x1_t a, uint64x1_t b) {
 //   return vshl_n_s64(a, 1);
 // }
 
-// NYI-LABEL: @test_vshld_n_u64(
-// NYI:   [[SHLD_N:%.*]] = shl i64 %a, 63
-// NYI:   ret i64 [[SHLD_N]]
-// uint64_t test_vshld_n_u64(uint64_t a) {
-//   return (uint64_t)vshld_n_u64(a, 63);
-// }
+uint64_t test_vshld_n_u64(uint64_t a) {
+  return (uint64_t)vshld_n_u64(a, 63);
+
+  // CIR-LABEL: vshld_n_u64
+  // CIR: {{%.*}} = cir.shift(left, {{%.*}} : !u64i, {{%.*}} : !u64i) -> !u64i
+
+  // LLVM-LABEL: @test_vshld_n_u64(
+  // LLVM:   [[SHLD_N:%.*]] = shl i64 %0, 63
+  // LLVM:   ret i64 [[SHLD_N]]
+}
 
 // NYI-LABEL: @test_vshl_n_u64(
 // NYI:   [[TMP0:%.*]] = bitcast <1 x i64> %a to <8 x i8>