Change behaviour for zero-sized value types of array-related types; Fix make behaviour to always zero memory

4 files changed, 58 insertions, 113 deletions

diff --git a/core/mem/alloc.odin b/core/mem/alloc.odin
index 767e59183..fda7862c3 100644
--- a/core/mem/alloc.odin
+++ b/core/mem/alloc.odin
@@ -111,7 +111,10 @@ make_slice :: inline proc($T: typeid/[]$E, auto_cast len: int, allocator := cont
 make_aligned :: proc($T: typeid/[]$E, auto_cast len: int, alignment: int, allocator := context.allocator, loc := #caller_location) -> T {
 	runtime.make_slice_error_loc(loc, len);
 	data := alloc(size_of(E)*len, alignment, allocator, loc);
-	if data == nil do return nil;
+	if data == nil && size_of(E) != 0 {
+		return nil;
+	}
+	zero(data, size_of(E)*len);
 	s := Raw_Slice{data, len};
 	return transmute(T)s;
 }
@@ -125,9 +128,10 @@ make_dynamic_array_len_cap :: proc($T: typeid/[dynamic]$E, auto_cast len: int, a
 	runtime.make_dynamic_array_error_loc(loc, len, cap);
 	data := alloc(size_of(E)*cap, align_of(E), allocator, loc);
 	s := Raw_Dynamic_Array{data, len, cap, allocator};
-	if data == nil {
+	if data == nil && size_of(E) != 0 {
 		s.len, s.cap = 0, 0;
 	}
+	zero(data, size_of(E)*len);
 	return transmute(T)s;
 }
 make_map :: proc($T: typeid/map[$K]$E, auto_cast cap: int = 16, allocator := context.allocator, loc := #caller_location) -> T {
diff --git a/core/runtime/core.odin b/core/runtime/core.odin
index d906c28b7..b66f43788 100644
--- a/core/runtime/core.odin
+++ b/core/runtime/core.odin
@@ -609,7 +609,10 @@ new_clone :: inline proc(data: $T, allocator := context.allocator, loc := #calle
 make_aligned :: proc($T: typeid/[]$E, auto_cast len: int, alignment: int, allocator := context.allocator, loc := #caller_location) -> T {
 	make_slice_error_loc(loc, len);
 	data := mem_alloc(size_of(E)*len, alignment, allocator, loc);
-	if data == nil do return nil;
+	if data == nil && size_of(E) != 0 {
+		return nil;
+	}
+	mem_zero(data, size_of(E)*len);
 	s := Raw_Slice{data, len};
 	return transmute(T)s;
 }
@@ -634,9 +637,10 @@ make_dynamic_array_len_cap :: proc($T: typeid/[dynamic]$E, auto_cast len: int, a
 	make_dynamic_array_error_loc(loc, len, cap);
 	data := mem_alloc(size_of(E)*cap, align_of(E), allocator, loc);
 	s := Raw_Dynamic_Array{data, len, cap, allocator};
-	if data == nil {
+	if data == nil && size_of(E) != 0 {
 		s.len, s.cap = 0, 0;
 	}
+	mem_zero(data, size_of(E)*cap);
 	return transmute(T)s;
 }
 
@@ -697,10 +701,12 @@ append_elem :: proc(array: ^$T/[dynamic]$E, arg: E, loc := #caller_location)  {
 	arg_len = min(cap(array)-len(array), arg_len);
 	if arg_len > 0 {
 		a := (^Raw_Dynamic_Array)(array);
-		data := (^E)(a.data);
-		assert(data != nil);
-		val := arg;
-		mem_copy(ptr_offset(data, a.len), &val, size_of(E));
+		if size_of(E) != 0 {
+			data := (^E)(a.data);
+			assert(data != nil);
+			val := arg;
+			mem_copy(ptr_offset(data, a.len), &val, size_of(E));
+		}
 		a.len += arg_len;
 	}
 }
@@ -719,9 +725,11 @@ append_elems :: proc(array: ^$T/[dynamic]$E, args: ..E, loc := #caller_location)
 	arg_len = min(cap(array)-len(array), arg_len);
 	if arg_len > 0 {
 		a := (^Raw_Dynamic_Array)(array);
-		data := (^E)(a.data);
-		assert(data != nil);
-		mem_copy(ptr_offset(data, a.len), &args[0], size_of(E) * arg_len);
+		if size_of(E) != 0 {
+			data := (^E)(a.data);
+			assert(data != nil);
+			mem_copy(ptr_offset(data, a.len), &args[0], size_of(E) * arg_len);
+		}
 		a.len += arg_len;
 	}
 }
diff --git a/src/ir.cpp b/src/ir.cpp
index 9b8eac02f..c01876b5d 100644
--- a/src/ir.cpp
+++ b/src/ir.cpp
@@ -4414,6 +4414,7 @@ irValue *ir_emit_comp_against_nil(irProcedure *proc, TokenKind op_kind, irValue
 		irValue *ptr = ir_emit_conv(proc, x, t_u8_ptr);
 		return ir_emit_comp(proc, op_kind, ptr, v_raw_nil);
 	} else if (is_type_any(t)) {
+		// TODO(bill): is this correct behaviour for nil comparison for any?
 		irValue *data = ir_emit_struct_ev(proc, x, 0);
 		irValue *ti   = ir_emit_struct_ev(proc, x, 1);
 		if (op_kind == Token_CmpEq) {
@@ -4426,32 +4427,14 @@ irValue *ir_emit_comp_against_nil(irProcedure *proc, TokenKind op_kind, irValue
 			return ir_emit_arith(proc, Token_And, a, b, t_bool);
 		}
 	} else if (is_type_slice(t)) {
-		irValue *data = ir_emit_struct_ev(proc, x, 0);
-		irValue *cap  = ir_emit_struct_ev(proc, x, 1);
-		if (op_kind == Token_CmpEq) {
-			irValue *a = ir_emit_comp(proc, Token_CmpEq, data, v_raw_nil);
-			irValue *b = ir_emit_comp(proc, Token_CmpEq, cap, v_zero);
-			return ir_emit_arith(proc, Token_Or, a, b, t_bool);
-		} else if (op_kind == Token_NotEq) {
-			irValue *a = ir_emit_comp(proc, Token_NotEq, data, v_raw_nil);
-			irValue *b = ir_emit_comp(proc, Token_NotEq, cap, v_zero);
-			return ir_emit_arith(proc, Token_And, a, b, t_bool);
-		}
+		irValue *len  = ir_emit_struct_ev(proc, x, 1);
+		return ir_emit_comp(proc, op_kind, len, v_zero);
 	} else if (is_type_dynamic_array(t)) {
-		irValue *data = ir_emit_struct_ev(proc, x, 0);
 		irValue *cap  = ir_emit_struct_ev(proc, x, 2);
-		if (op_kind == Token_CmpEq) {
-			irValue *a = ir_emit_comp(proc, Token_CmpEq, data, v_raw_nil);
-			irValue *b = ir_emit_comp(proc, Token_CmpEq, cap, v_zero);
-			return ir_emit_arith(proc, Token_Or, a, b, t_bool);
-		} else if (op_kind == Token_NotEq) {
-			irValue *a = ir_emit_comp(proc, Token_NotEq, data, v_raw_nil);
-			irValue *b = ir_emit_comp(proc, Token_NotEq, cap, v_zero);
-			return ir_emit_arith(proc, Token_And, a, b, t_bool);
-		}
+		return ir_emit_comp(proc, op_kind, cap, v_zero);
 	} else if (is_type_map(t)) {
-		irValue *len = ir_map_len(proc, x);
-		return ir_emit_comp(proc, op_kind, len, v_zero);
+		irValue *cap = ir_map_cap(proc, x);
+		return ir_emit_comp(proc, op_kind, cap, v_zero);
 	} else if (is_type_union(t)) {
 		if (type_size_of(t) == 0) {
 			return ir_emit_comp(proc, op_kind, v_zero, v_zero);
@@ -4481,38 +4464,12 @@ irValue *ir_emit_comp_against_nil(irProcedure *proc, TokenKind op_kind, irValue
 		if (bt->Struct.soa_kind == StructSoa_Slice) {
 			ir_emit_comment(proc, str_lit("soa-slice-nil-comp"));
 			irValue *len  = ir_soa_struct_len(proc, x);
-			if (bt->Struct.fields.count > 1) {
-				irValue *data = ir_emit_struct_ev(proc, x, 0);
-				if (op_kind == Token_CmpEq) {
-					irValue *a = ir_emit_comp(proc, Token_CmpEq, data, v_raw_nil);
-					irValue *b = ir_emit_comp(proc, Token_CmpEq, len, v_zero);
-					return ir_emit_arith(proc, Token_Or, a, b, t_bool);
-				} else if (op_kind == Token_NotEq) {
-					irValue *a = ir_emit_comp(proc, Token_NotEq, data, v_raw_nil);
-					irValue *b = ir_emit_comp(proc, Token_NotEq, len, v_zero);
-					return ir_emit_arith(proc, Token_And, a, b, t_bool);
-				}
-			} else {
-				return ir_emit_comp(proc, op_kind, len, v_zero);
-			}
+			return ir_emit_comp(proc, op_kind, len, v_zero);
 		} else if (bt->Struct.soa_kind == StructSoa_Dynamic) {
 			ir_emit_comment(proc, str_lit("soa-dynamic-array-nil-comp"));
 
-			irValue *cap  = ir_soa_struct_len(proc, x);
-			if (bt->Struct.fields.count > 1) {
-				irValue *data = ir_emit_struct_ev(proc, x, 0);
-				if (op_kind == Token_CmpEq) {
-					irValue *a = ir_emit_comp(proc, Token_CmpEq, data, v_raw_nil);
-					irValue *b = ir_emit_comp(proc, Token_CmpEq, cap, v_zero);
-					return ir_emit_arith(proc, Token_Or, a, b, t_bool);
-				} else if (op_kind == Token_NotEq) {
-					irValue *a = ir_emit_comp(proc, Token_NotEq, data, v_raw_nil);
-					irValue *b = ir_emit_comp(proc, Token_NotEq, cap, v_zero);
-					return ir_emit_arith(proc, Token_And, a, b, t_bool);
-				}
-			} else {
-				return ir_emit_comp(proc, op_kind, cap, v_zero);
-			}
+			irValue *cap  = ir_soa_struct_cap(proc, x);
+			return ir_emit_comp(proc, op_kind, cap, v_zero);
 		}
 	}
 	return nullptr;
diff --git a/src/llvm_backend.cpp b/src/llvm_backend.cpp
index 68d288799..c308f5746 100644
--- a/src/llvm_backend.cpp
+++ b/src/llvm_backend.cpp
@@ -7952,6 +7952,7 @@ lbValue lb_emit_comp_against_nil(lbProcedure *p, TokenKind op_kind, lbValue x) {
 		}
 		return res;
 	} else if (is_type_any(t)) {
+		// TODO(bill): is this correct behaviour for nil comparison for any?
 		lbValue data = lb_emit_struct_ev(p, x, 0);
 		lbValue ti   = lb_emit_struct_ev(p, x, 1);
 		if (op_kind == Token_CmpEq) {
@@ -7966,31 +7967,21 @@ lbValue lb_emit_comp_against_nil(lbProcedure *p, TokenKind op_kind, lbValue x) {
 			return res;
 		}
 	} else if (is_type_slice(t)) {
-		lbValue data = lb_emit_struct_ev(p, x, 0);
-		lbValue cap  = lb_emit_struct_ev(p, x, 1);
+		lbValue len  = lb_emit_struct_ev(p, x, 1);
 		if (op_kind == Token_CmpEq) {
-			LLVMValueRef a = LLVMBuildIsNull(p->builder, data.value, "");
-			LLVMValueRef b = LLVMBuildIsNull(p->builder, cap.value, "");
-			res.value = LLVMBuildOr(p->builder, a, b, "");
+			res.value = LLVMBuildIsNull(p->builder, len.value, "");
 			return res;
 		} else if (op_kind == Token_NotEq) {
-			LLVMValueRef a = LLVMBuildIsNotNull(p->builder, data.value, "");
-			LLVMValueRef b = LLVMBuildIsNotNull(p->builder, cap.value, "");
-			res.value = LLVMBuildAnd(p->builder, a, b, "");
+			res.value = LLVMBuildIsNotNull(p->builder, len.value, "");
 			return res;
 		}
 	} else if (is_type_dynamic_array(t)) {
-		lbValue data = lb_emit_struct_ev(p, x, 0);
 		lbValue cap  = lb_emit_struct_ev(p, x, 2);
 		if (op_kind == Token_CmpEq) {
-			LLVMValueRef a = LLVMBuildIsNull(p->builder, data.value, "");
-			LLVMValueRef b = LLVMBuildIsNull(p->builder, cap.value, "");
-			res.value = LLVMBuildOr(p->builder, a, b, "");
+			res.value = LLVMBuildIsNull(p->builder, cap.value, "");
 			return res;
 		} else if (op_kind == Token_NotEq) {
-			LLVMValueRef a = LLVMBuildIsNotNull(p->builder, data.value, "");
-			LLVMValueRef b = LLVMBuildIsNotNull(p->builder, cap.value, "");
-			res.value = LLVMBuildAnd(p->builder, a, b, "");
+			res.value = LLVMBuildIsNotNull(p->builder, cap.value, "");
 			return res;
 		}
 	} else if (is_type_map(t)) {
@@ -8019,41 +8010,26 @@ lbValue lb_emit_comp_against_nil(lbProcedure *p, TokenKind op_kind, lbValue x) {
 		lbValue res = lb_emit_comp(p, op_kind, val, lb_const_int(p->module, t_int, 0));
 		return res;
 	} else if (is_type_soa_struct(t)) {
-		GB_PANIC("#soa struct nil comparison");
-		// Type *bt = base_type(t);
-		// if (bt->Struct.soa_kind == StructSoa_Slice) {
-		// 	lbValue len  = lb_soa_struct_len(p, x);
-		// 	if (bt->Struct.fields.count > 1) {
-		// 		lbValue data = lb_emit_struct_ev(p, x, 0);
-		// 		if (op_kind == Token_CmpEq) {
-		// 			lbValue a = lb_emit_comp(p, Token_CmpEq, data, v_raw_nil);
-		// 			lbValue b = lb_emit_comp(p, Token_CmpEq, len, v_zero);
-		// 			return lb_emit_arith(p, Token_Or, a, b, t_bool);
-		// 		} else if (op_kind == Token_NotEq) {
-		// 			lbValue a = lb_emit_comp(p, Token_NotEq, data, v_raw_nil);
-		// 			lbValue b = lb_emit_comp(p, Token_NotEq, len, v_zero);
-		// 			return lb_emit_arith(p, Token_And, a, b, t_bool);
-		// 		}
-		// 	} else {
-		// 		return lb_emit_comp(p, op_kind, len, v_zero);
-		// 	}
-		// } else if (bt->Struct.soa_kind == StructSoa_Dynamic) {
-		// 	lbValue cap  = lb_soa_struct_len(p, x);
-		// 	if (bt->Struct.fields.count > 1) {
-		// 		lbValue data = lb_emit_struct_ev(p, x, 0);
-		// 		if (op_kind == Token_CmpEq) {
-		// 			lbValue a = lb_emit_comp(p, Token_CmpEq, data, v_raw_nil);
-		// 			lbValue b = lb_emit_comp(p, Token_CmpEq, cap, v_zero);
-		// 			return lb_emit_arith(p, Token_Or, a, b, t_bool);
-		// 		} else if (op_kind == Token_NotEq) {
-		// 			lbValue a = lb_emit_comp(p, Token_NotEq, data, v_raw_nil);
-		// 			lbValue b = lb_emit_comp(p, Token_NotEq, cap, v_zero);
-		// 			return lb_emit_arith(p, Token_And, a, b, t_bool);
-		// 		}
-		// 	} else {
-		// 		return lb_emit_comp(p, op_kind, cap, v_zero);
-		// 	}
-		// }
+		Type *bt = base_type(t);
+		if (bt->Struct.soa_kind == StructSoa_Slice) {
+			lbValue len = lb_soa_struct_len(p, x);
+			if (op_kind == Token_CmpEq) {
+				res.value = LLVMBuildIsNull(p->builder, len.value, "");
+				return res;
+			} else if (op_kind == Token_NotEq) {
+				res.value = LLVMBuildIsNotNull(p->builder, len.value, "");
+				return res;
+			}
+		} else if (bt->Struct.soa_kind == StructSoa_Dynamic) {
+			lbValue cap = lb_soa_struct_cap(p, x);
+			if (op_kind == Token_CmpEq) {
+				res.value = LLVMBuildIsNull(p->builder, cap.value, "");
+				return res;
+			} else if (op_kind == Token_NotEq) {
+				res.value = LLVMBuildIsNotNull(p->builder, cap.value, "");
+				return res;
+			}
+		}
 	}
 	return {};
 }