Replace many `foreign` llvm calls with intrinsics

1 files changed, 22 insertions, 0 deletions

diff --git a/src/llvm_backend.cpp b/src/llvm_backend.cpp
index 3e7d858ed..cefe740f0 100644
--- a/src/llvm_backend.cpp
+++ b/src/llvm_backend.cpp
@@ -9108,6 +9108,8 @@ lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValue const &tv,
 
 	case BuiltinProc_trailing_zeros:
 		return lb_emit_trailing_zeros(p, lb_build_expr(p, ce->args[0]), tv.type);
+	case BuiltinProc_leading_zeros:
+		return lb_emit_leading_zeros(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);
@@ -9989,6 +9991,26 @@ lbValue lb_emit_trailing_zeros(lbProcedure *p, lbValue x, Type *type) {
 	return res;
 }
 
+lbValue lb_emit_leading_zeros(lbProcedure *p, lbValue x, Type *type) {
+	x = lb_emit_conv(p, x, type);
+
+	char const *name = "llvm.ctlz";
+	LLVMTypeRef types[1] = {lb_type(p->module, type)};
+	unsigned id = LLVMLookupIntrinsicID(name, gb_strlen(name));
+	GB_ASSERT_MSG(id != 0, "Unable to find %s.%s", name, LLVMPrintTypeToString(types[0]));
+	LLVMValueRef ip = LLVMGetIntrinsicDeclaration(p->module->mod, id, types, gb_count_of(types));
+
+	LLVMValueRef args[2] = {};
+	args[0] = x.value;
+	args[1] = LLVMConstNull(LLVMInt1TypeInContext(p->module->ctx));
+
+	lbValue res = {};
+	res.value = LLVMBuildCall(p->builder, ip, args, gb_count_of(args), "");
+	res.type = type;
+	return res;
+}
+
+
 
 lbValue lb_emit_reverse_bits(lbProcedure *p, lbValue x, Type *type) {
 	x = lb_emit_conv(p, x, type);