Add `simd_add_sat` `simd_sub_sat`

core/intrinsics/intrinsics.odin

@@ -202,6 +202,9 @@ simd_shr :: proc(a: #simd[N]T, b: #simd[N]Unsigned_Integer) -> #simd[N]T ---
 simd_shl_masked :: proc(a: #simd[N]T, b: #simd[N]Unsigned_Integer) -> #simd[N]T ---
 simd_shr_masked :: proc(a: #simd[N]T, b: #simd[N]Unsigned_Integer) -> #simd[N]T ---
 
+simd_add_sat :: proc(a, b: #simd[N]T) -> #simd[N]T ---
+simd_sub_sat :: proc(a, b: #simd[N]T) -> #simd[N]T ---
+
 simd_and :: proc(a, b: #simd[N]T) -> #simd[N]T ---
 simd_or  :: proc(a, b: #simd[N]T) -> #simd[N]T ---
 simd_xor :: proc(a, b: #simd[N]T) -> #simd[N]T ---
@@ -238,13 +241,15 @@ simd_reduce_xor         :: proc(a: #simd[N]T) -> T ---
 simd_shuffle :: proc(a, b: #simd[N]T, indices: ..int) -> #simd[len(indices)]T ---
 simd_select  :: proc(cond: #simd[N]boolean_or_integer, true, false: #simd[N]T) -> #simd[N]T ---
 
-
-simd_sqrt    :: proc(a: #simd[N]any_float) -> #simd[N]any_float ---
+// Lane-wise operations
+simd_sqrt    :: proc(a: #simd[N]any_float) -> #simd[N]any_float --- // IEEE sqrt
 simd_ceil    :: proc(a: #simd[N]any_float) -> #simd[N]any_float ---
 simd_floor   :: proc(a: #simd[N]any_float) -> #simd[N]any_float ---
 simd_trunc   :: proc(a: #simd[N]any_float) -> #simd[N]any_float ---
+// rounding to the nearest integral value; if two values are equally near, rounds to the even one
 simd_nearest :: proc(a: #simd[N]any_float) -> #simd[N]any_float ---
 
+// equivalent a swizzle with descending indices, e.g. reserve(a, 3, 2, 1, 0)
 simd_reverse :: proc(a: #simd[N]T) -> #simd[N]T ---
 
 // WASM targets only

core/simd/simd.odin

@@ -39,6 +39,10 @@ shr :: intrinsics.simd_shr
 shl_masked :: intrinsics.simd_shl_masked
 shr_masked :: intrinsics.simd_shr_masked
 
+// Saturation Arithmetic
+add_sat :: intrinsics.simd_add_sat
+sub_sat :: intrinsics.simd_sub_sat
+
 and :: intrinsics.simd_and
 or  :: intrinsics.simd_or
 xor :: intrinsics.simd_xor

src/check_builtin.cpp

@@ -458,6 +458,8 @@ bool check_builtin_simd_operation(CheckerContext *c, Operand *operand, Ast *call
 		}
 
 	// Integer only
+	case BuiltinProc_simd_add_sat:
+	case BuiltinProc_simd_sub_sat:
 	case BuiltinProc_simd_rem:
 	case BuiltinProc_simd_and:
 	case BuiltinProc_simd_or:
@@ -486,20 +488,25 @@ bool check_builtin_simd_operation(CheckerContext *c, Operand *operand, Ast *call
 			}
 			Type *elem = base_array_type(x.type);
 
-			if (id == BuiltinProc_simd_rem) {
+			switch (id) {
+			case BuiltinProc_simd_add_sat:
+			case BuiltinProc_simd_sub_sat:
+			case BuiltinProc_simd_rem:
 				if (!is_type_integer(elem)) {
 					gbString xs = type_to_string(x.type);
 					error(x.expr, "'%.*s' expected a #simd type with an integer element, got '%s'", LIT(builtin_name), xs);
 					gb_string_free(xs);
 					return false;
 				}
-			} else {
+				break;
+			default:
 				if (!is_type_integer(elem) && !is_type_boolean(elem)) {
 					gbString xs = type_to_string(x.type);
 					error(x.expr, "'%.*s' expected a #simd type with an integer or boolean element, got '%s'", LIT(builtin_name), xs);
 					gb_string_free(xs);
 					return false;
 				}
+				break;
 			}
 
 			operand->mode = Addressing_Value;

src/checker_builtin_procs.hpp

@@ -129,6 +129,9 @@ BuiltinProc__simd_begin,
 	BuiltinProc_simd_shl_masked, // C logic
 	BuiltinProc_simd_shr_masked, // C logic
 
+	BuiltinProc_simd_add_sat, // saturation arithmetic
+	BuiltinProc_simd_sub_sat, // saturation arithmetic
+
 	BuiltinProc_simd_and,
 	BuiltinProc_simd_or,
 	BuiltinProc_simd_xor,
@@ -402,6 +405,10 @@ gb_global BuiltinProc builtin_procs[BuiltinProc_COUNT] = {
 	{STR_LIT("simd_shr"), 2, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("simd_shl_masked"), 2, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("simd_shr_masked"), 2, false, Expr_Expr, BuiltinProcPkg_intrinsics},
+
+	{STR_LIT("simd_add_sat"), 2, false, Expr_Expr, BuiltinProcPkg_intrinsics},
+	{STR_LIT("simd_sub_sat"), 2, false, Expr_Expr, BuiltinProcPkg_intrinsics},
+
 	{STR_LIT("simd_and"), 2, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("simd_or"),  2, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("simd_xor"), 2, false, Expr_Expr, BuiltinProcPkg_intrinsics},

src/llvm_backend_proc.cpp

@@ -1353,6 +1353,30 @@ lbValue lb_build_builtin_simd_proc(lbProcedure *p, Ast *expr, TypeAndValue const
 			return res;
 		}
 
+	case BuiltinProc_simd_add_sat:
+	case BuiltinProc_simd_sub_sat:
+		{
+			arg1 = lb_build_expr(p, ce->args[1]);
+
+			char const *name = nullptr;
+			switch (builtin_id) {
+			case BuiltinProc_simd_add_sat: name = is_signed ? "llvm.sadd.sat" : "llvm.uadd.sat"; break;
+			case BuiltinProc_simd_sub_sat: name = is_signed ? "llvm.ssub.sat" : "llvm.usub.sat"; break;
+			}
+
+			LLVMTypeRef types[1] = {lb_type(p->module, arg0.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] = arg0.value;
+			args[1] = arg1.value;
+
+			res.value = LLVMBuildCall(p->builder, ip, args, gb_count_of(args), "");
+			return res;
+		}
+
 
 	}
 	GB_PANIC("Unhandled simd intrinsic: '%.*s'", LIT(builtin_procs[builtin_id].name));