Add `intrinsics.count_trailing_ones` and `intrinsics.count_leading_ones`

4 files changed, 45 insertions, 0 deletions

diff --git a/src/check_builtin.cpp b/src/check_builtin.cpp
index e2428576e..1a094c1f0 100644
--- a/src/check_builtin.cpp
+++ b/src/check_builtin.cpp
@@ -5204,6 +5204,8 @@ gb_internal bool check_builtin_procedure(CheckerContext *c, Operand *operand, As
 	case BuiltinProc_count_zeros:
 	case BuiltinProc_count_trailing_zeros:
 	case BuiltinProc_count_leading_zeros:
+	case BuiltinProc_count_trailing_ones:
+	case BuiltinProc_count_leading_ones:
 	case BuiltinProc_reverse_bits:
 		{
 			Operand x = {};
@@ -5301,6 +5303,27 @@ gb_internal bool check_builtin_procedure(CheckerContext *c, Operand *operand, As
 							v += 1;
 						}
 						break;
+
+					case BuiltinProc_count_trailing_ones:
+						for (u64 i = 0; i < bit_size; i++) {
+							u8 b = cast(u8)(i & 7);
+							u8 j = cast(u8)(i >> 3);
+							if ((rop[j] & (1 << b)) == 0) {
+								break;
+							}
+							v += 1;
+						}
+						break;
+					case BuiltinProc_count_leading_ones:
+						for (u64 i = bit_size-1; i < bit_size; i--) {
+							u8 b = cast(u8)(i & 7);
+							u8 j = cast(u8)(i >> 3);
+							if ((rop[j] & (1 << b)) == 0) {
+								break;
+							}
+							v += 1;
+						}
+						break;
 					}
 
 
diff --git a/src/checker_builtin_procs.hpp b/src/checker_builtin_procs.hpp
index 5b446cc1c..a13ffc3cd 100644
--- a/src/checker_builtin_procs.hpp
+++ b/src/checker_builtin_procs.hpp
@@ -74,6 +74,8 @@ enum BuiltinProcId {
 	BuiltinProc_count_zeros,
 	BuiltinProc_count_trailing_zeros,
 	BuiltinProc_count_leading_zeros,
+	BuiltinProc_count_trailing_ones,
+	BuiltinProc_count_leading_ones,
 	BuiltinProc_reverse_bits,
 	BuiltinProc_byte_swap,
 
@@ -453,6 +455,8 @@ gb_global BuiltinProc builtin_procs[BuiltinProc_COUNT] = {
 	{STR_LIT("count_zeros"),          1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("count_trailing_zeros"), 1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("count_leading_zeros"),  1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
+	{STR_LIT("count_trailing_ones"),  1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
+	{STR_LIT("count_leading_ones"),   1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("reverse_bits"),         1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("byte_swap"),            1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 
diff --git a/src/llvm_backend_proc.cpp b/src/llvm_backend_proc.cpp
index b596f15ef..e52e91f75 100644
--- a/src/llvm_backend_proc.cpp
+++ b/src/llvm_backend_proc.cpp
@@ -2850,6 +2850,12 @@ gb_internal lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValu
 	case BuiltinProc_count_leading_zeros:
 		return lb_emit_count_leading_zeros(p, lb_build_expr(p, ce->args[0]), tv.type);
 
+	case BuiltinProc_count_trailing_ones:
+		return lb_emit_count_trailing_ones(p, lb_build_expr(p, ce->args[0]), tv.type);
+	case BuiltinProc_count_leading_ones:
+		return lb_emit_count_leading_ones(p, lb_build_expr(p, ce->args[0]), tv.type);
+
+
 	case BuiltinProc_count_ones:
 		return lb_emit_count_ones(p, lb_build_expr(p, ce->args[0]), tv.type);
 	case BuiltinProc_count_zeros:
diff --git a/src/llvm_backend_utility.cpp b/src/llvm_backend_utility.cpp
index 367e7be75..8a7bced59 100644
--- a/src/llvm_backend_utility.cpp
+++ b/src/llvm_backend_utility.cpp
@@ -648,6 +648,18 @@ gb_internal lbValue lb_emit_count_leading_zeros(lbProcedure *p, lbValue x, Type
 	return res;
 }
 
+gb_internal lbValue lb_emit_unary_arith(lbProcedure *p, TokenKind op, lbValue x, Type *type);
+
+gb_internal lbValue lb_emit_count_trailing_ones(lbProcedure *p, lbValue x, Type *type) {
+	lbValue z = lb_emit_unary_arith(p, Token_Xor, x, type);
+	return lb_emit_count_trailing_zeros(p, z, type);
+}
+
+gb_internal lbValue lb_emit_count_leading_ones(lbProcedure *p, lbValue x, Type *type) {
+	lbValue z = lb_emit_unary_arith(p, Token_Xor, x, type);
+	return lb_emit_count_leading_zeros(p, z, type);
+}
+
 
 
 gb_internal lbValue lb_emit_reverse_bits(lbProcedure *p, lbValue x, Type *type) {