Add `intrinsics.mem_zero`

3 files changed, 57 insertions, 2 deletions

diff --git a/src/check_builtin.cpp b/src/check_builtin.cpp
index 1acb9732f..1630b5b7d 100644
--- a/src/check_builtin.cpp
+++ b/src/check_builtin.cpp
@@ -2106,6 +2106,47 @@ bool check_builtin_procedure(CheckerContext *c, Operand *operand, Ast *call, i32
 		}
 		break;
 
+	case BuiltinProc_mem_zero:
+		{
+			operand->mode = Addressing_NoValue;
+			operand->type = t_invalid;
+
+			Operand ptr = {};
+			Operand len = {};
+			check_expr(c, &ptr, ce->args[0]);
+			check_expr(c, &len, ce->args[1]);
+			if (ptr.mode == Addressing_Invalid) {
+				return false;
+			}
+			if (len.mode == Addressing_Invalid) {
+				return false;
+			}
+
+
+			if (!is_type_pointer(ptr.type)) {
+				gbString str = type_to_string(ptr.type);
+				error(ptr.expr, "Expected a pointer value for '%.*s', got %s", LIT(builtin_procs[id].name), str);
+				gb_string_free(str);
+				return false;
+			}
+			if (!is_type_integer(len.type)) {
+				gbString str = type_to_string(len.type);
+				error(len.expr, "Expected an integer value for the number of bytes for '%.*s', got %s", LIT(builtin_procs[id].name), str);
+				gb_string_free(str);
+				return false;
+			}
+
+			if (len.mode == Addressing_Constant) {
+				i64 n = exact_value_to_i64(len.value);
+				if (n < 0) {
+					gbString str = expr_to_string(len.expr);
+					error(len.expr, "Expected a non-negative integer value for the number of bytes for '%.*s', got %s", LIT(builtin_procs[id].name), str);
+					gb_string_free(str);
+				}
+			}
+		}
+		break;
+
 
 	case BuiltinProc_atomic_fence:
 	case BuiltinProc_atomic_fence_acq:
diff --git a/src/checker_builtin_procs.hpp b/src/checker_builtin_procs.hpp
index b69bacd30..4fd97f804 100644
--- a/src/checker_builtin_procs.hpp
+++ b/src/checker_builtin_procs.hpp
@@ -60,6 +60,7 @@ enum BuiltinProcId {
 
 	BuiltinProc_mem_copy,
 	BuiltinProc_mem_copy_non_overlapping,
+	BuiltinProc_mem_zero,
 
 	BuiltinProc_volatile_store,
 	BuiltinProc_volatile_load,
@@ -287,6 +288,7 @@ gb_global BuiltinProc builtin_procs[BuiltinProc_COUNT] = {
 
 	{STR_LIT("mem_copy"),                 3, false, Expr_Stmt, BuiltinProcPkg_intrinsics},
 	{STR_LIT("mem_copy_non_overlapping"), 3, false, Expr_Stmt, BuiltinProcPkg_intrinsics},
+	{STR_LIT("mem_zero"),                 2, false, Expr_Stmt, BuiltinProcPkg_intrinsics},
 
 	{STR_LIT("volatile_store"),  2, false, Expr_Stmt, BuiltinProcPkg_intrinsics},
 	{STR_LIT("volatile_load"),   1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
diff --git a/src/llvm_backend.cpp b/src/llvm_backend.cpp
index b622d1729..74c6cfc11 100644
--- a/src/llvm_backend.cpp
+++ b/src/llvm_backend.cpp
@@ -9478,8 +9478,6 @@ lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValue const &tv,
 	case BuiltinProc_mem_copy:
 	case BuiltinProc_mem_copy_non_overlapping:
 		{
-
-
 			lbValue dst = lb_build_expr(p, ce->args[0]);
 			lbValue src = lb_build_expr(p, ce->args[1]);
 			lbValue len = lb_build_expr(p, ce->args[2]);
@@ -9513,6 +9511,20 @@ lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValue const &tv,
 			return {};
 		}
 
+	case BuiltinProc_mem_zero:
+		{
+			lbValue ptr = lb_build_expr(p, ce->args[0]);
+			lbValue len = lb_build_expr(p, ce->args[1]);
+			ptr = lb_emit_conv(p, ptr, t_rawptr);
+			len = lb_emit_conv(p, len, t_int);
+
+			LLVMTypeRef type_i8 = LLVMInt8TypeInContext(p->module->ctx);
+			unsigned alignment = 1;
+			LLVMBuildMemSet(p->builder, ptr.value, LLVMConstNull(type_i8), len.value, alignment);
+
+			return {};
+		}
+
 
 	case BuiltinProc_atomic_fence:
 		LLVMBuildFence(p->builder, LLVMAtomicOrderingSequentiallyConsistent, false, "");