Commit 64e319f555
Changed files (5)
src/AstGen.zig
@@ -851,9 +851,18 @@ fn expr(gz: *GenZir, scope: *Scope, ri: ResultInfo, node: Ast.Node.Index) InnerE
.slice => {
const extra = tree.extraData(node_datas[node].rhs, Ast.Node.Slice);
const lhs_node = node_datas[node].lhs;
- if (node_tags[lhs_node] == .slice_open and nodeIsTriviallyZero(tree, extra.start)) {
+ const lhs_tag = node_tags[lhs_node];
+ const lhs_is_slice_sentinel = lhs_tag == .slice_sentinel;
+ const lhs_is_open_slice = lhs_tag == .slice_open or
+ (lhs_is_slice_sentinel and tree.extraData(node_datas[lhs_node].rhs, Ast.Node.SliceSentinel).end == 0);
+ if (lhs_is_open_slice and nodeIsTriviallyZero(tree, extra.start)) {
const lhs = try expr(gz, scope, .{ .rl = .ref }, node_datas[lhs_node].lhs);
- const start = try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, node_datas[lhs_node].rhs);
+
+ const start = if (lhs_is_slice_sentinel) start: {
+ const lhs_extra = tree.extraData(node_datas[lhs_node].rhs, Ast.Node.SliceSentinel);
+ break :start try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, lhs_extra.start);
+ } else try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, node_datas[lhs_node].rhs);
+
const cursor = maybeAdvanceSourceCursorToMainToken(gz, node);
const len = if (extra.end != 0) try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, extra.end) else .none;
try emitDbgStmt(gz, cursor);
@@ -862,6 +871,7 @@ fn expr(gz: *GenZir, scope: *Scope, ri: ResultInfo, node: Ast.Node.Index) InnerE
.start = start,
.len = len,
.start_src_node_offset = gz.nodeIndexToRelative(lhs_node),
+ .sentinel = .none,
});
return rvalue(gz, ri, result, node);
}
@@ -879,10 +889,36 @@ fn expr(gz: *GenZir, scope: *Scope, ri: ResultInfo, node: Ast.Node.Index) InnerE
return rvalue(gz, ri, result, node);
},
.slice_sentinel => {
+ const extra = tree.extraData(node_datas[node].rhs, Ast.Node.SliceSentinel);
+ const lhs_node = node_datas[node].lhs;
+ const lhs_tag = node_tags[lhs_node];
+ const lhs_is_slice_sentinel = lhs_tag == .slice_sentinel;
+ const lhs_is_open_slice = lhs_tag == .slice_open or
+ (lhs_is_slice_sentinel and tree.extraData(node_datas[lhs_node].rhs, Ast.Node.SliceSentinel).end == 0);
+ if (lhs_is_open_slice and nodeIsTriviallyZero(tree, extra.start)) {
+ const lhs = try expr(gz, scope, .{ .rl = .ref }, node_datas[lhs_node].lhs);
+
+ const start = if (lhs_is_slice_sentinel) start: {
+ const lhs_extra = tree.extraData(node_datas[lhs_node].rhs, Ast.Node.SliceSentinel);
+ break :start try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, lhs_extra.start);
+ } else try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, node_datas[lhs_node].rhs);
+
+ const cursor = maybeAdvanceSourceCursorToMainToken(gz, node);
+ const len = if (extra.end != 0) try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, extra.end) else .none;
+ const sentinel = try expr(gz, scope, .{ .rl = .none }, extra.sentinel);
+ try emitDbgStmt(gz, cursor);
+ const result = try gz.addPlNode(.slice_length, node, Zir.Inst.SliceLength{
+ .lhs = lhs,
+ .start = start,
+ .len = len,
+ .start_src_node_offset = gz.nodeIndexToRelative(lhs_node),
+ .sentinel = sentinel,
+ });
+ return rvalue(gz, ri, result, node);
+ }
const lhs = try expr(gz, scope, .{ .rl = .ref }, node_datas[node].lhs);
const cursor = maybeAdvanceSourceCursorToMainToken(gz, node);
- const extra = tree.extraData(node_datas[node].rhs, Ast.Node.SliceSentinel);
const start = try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, extra.start);
const end = if (extra.end != 0) try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, extra.end) else .none;
const sentinel = try expr(gz, scope, .{ .rl = .none }, extra.sentinel);
src/Autodoc.zig
@@ -1315,6 +1315,16 @@ fn walkInstruction(
extra.data.len,
false,
);
+ var sentinel_opt: ?DocData.WalkResult = if (extra.data.sentinel != .none)
+ try self.walkRef(
+ file,
+ parent_scope,
+ parent_src,
+ extra.data.sentinel,
+ false,
+ )
+ else
+ null;
const lhs_index = self.exprs.items.len;
try self.exprs.append(self.arena, lhs.expr);
@@ -1322,7 +1332,12 @@ fn walkInstruction(
try self.exprs.append(self.arena, start.expr);
const len_index = self.exprs.items.len;
try self.exprs.append(self.arena, len.expr);
- self.exprs.items[slice_index] = .{ .slice = .{ .lhs = lhs_index, .start = start_index, .end = len_index } };
+ const sentinel_index = if (sentinel_opt) |sentinel| sentinel_index: {
+ const index = self.exprs.items.len;
+ try self.exprs.append(self.arena, sentinel.expr);
+ break :sentinel_index index;
+ } else null;
+ self.exprs.items[slice_index] = .{ .slice = .{ .lhs = lhs_index, .start = start_index, .end = len_index, .sentinel = sentinel_index } };
return DocData.WalkResult{
.typeRef = self.decls.items[lhs.expr.declRef.Analyzed].value.typeRef,
src/print_zir.zig
@@ -765,6 +765,10 @@ const Writer = struct {
try self.writeInstRef(stream, extra.start);
try stream.writeAll(", ");
try self.writeInstRef(stream, extra.len);
+ if (extra.sentinel != .none) {
+ try stream.writeAll(", ");
+ try self.writeInstRef(stream, extra.sentinel);
+ }
try stream.writeAll(") ");
try self.writeSrc(stream, inst_data.src());
}
src/Sema.zig
@@ -9972,11 +9972,16 @@ fn zirSliceLength(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError
const array_ptr = try sema.resolveInst(extra.lhs);
const start = try sema.resolveInst(extra.start);
const len = try sema.resolveInst(extra.len);
+ const sentinel = try sema.resolveInst(extra.sentinel);
const ptr_src: LazySrcLoc = .{ .node_offset_slice_ptr = inst_data.src_node };
const start_src: LazySrcLoc = .{ .node_offset_slice_start = extra.start_src_node_offset };
const end_src: LazySrcLoc = .{ .node_offset_slice_end = inst_data.src_node };
+ const sentinel_src: LazySrcLoc = if (sentinel == .none)
+ .unneeded
+ else
+ .{ .node_offset_slice_sentinel = inst_data.src_node };
- return sema.analyzeSlice(block, src, array_ptr, start, len, .none, .unneeded, ptr_src, start_src, end_src, true);
+ return sema.analyzeSlice(block, src, array_ptr, start, len, sentinel, sentinel_src, ptr_src, start_src, end_src, true);
}
fn zirSwitchCapture(
@@ -29283,17 +29288,15 @@ fn analyzeSlice(
// we might learn of the length because it is a comptime-known slice value.
var end_is_len = uncasted_end_opt == .none;
const end = e: {
- if (by_length and !end_is_len) {
- if (!block.wantSafety()) break :e undefined;
- const len = try sema.coerce(block, Type.usize, uncasted_end_opt, end_src);
- const uncasted_end = try sema.analyzeArithmetic(block, .add, start, len, src, start_src, end_src, false);
- const end = try sema.coerce(block, Type.usize, uncasted_end, end_src);
- break :e end;
- } else if (array_ty.zigTypeTag() == .Array) {
+ if (array_ty.zigTypeTag() == .Array) {
const len_val = try Value.Tag.int_u64.create(sema.arena, array_ty.arrayLen());
if (!end_is_len) {
- const end = try sema.coerce(block, Type.usize, uncasted_end_opt, end_src);
+ const end = if (by_length) end: {
+ const len = try sema.coerce(block, Type.usize, uncasted_end_opt, end_src);
+ const uncasted_end = try sema.analyzeArithmetic(block, .add, start, len, src, start_src, end_src, false);
+ break :end try sema.coerce(block, Type.usize, uncasted_end, end_src);
+ } else try sema.coerce(block, Type.usize, uncasted_end_opt, end_src);
if (try sema.resolveMaybeUndefVal(end)) |end_val| {
const len_s_val = try Value.Tag.int_u64.create(
sema.arena,
@@ -29330,7 +29333,11 @@ fn analyzeSlice(
break :e try sema.addConstant(Type.usize, len_val);
} else if (slice_ty.isSlice()) {
if (!end_is_len) {
- const end = try sema.coerce(block, Type.usize, uncasted_end_opt, end_src);
+ const end = if (by_length) end: {
+ const len = try sema.coerce(block, Type.usize, uncasted_end_opt, end_src);
+ const uncasted_end = try sema.analyzeArithmetic(block, .add, start, len, src, start_src, end_src, false);
+ break :end try sema.coerce(block, Type.usize, uncasted_end, end_src);
+ } else try sema.coerce(block, Type.usize, uncasted_end_opt, end_src);
if (try sema.resolveDefinedValue(block, end_src, end)) |end_val| {
if (try sema.resolveMaybeUndefVal(ptr_or_slice)) |slice_val| {
if (slice_val.isUndef()) {
@@ -29399,66 +29406,64 @@ fn analyzeSlice(
const slice_sentinel = if (sentinel_opt != .none) sentinel else null;
// requirement: start <= end
- if (!by_length) {
- if (try sema.resolveDefinedValue(block, end_src, end)) |end_val| {
- if (try sema.resolveDefinedValue(block, start_src, start)) |start_val| {
- if (!(try sema.compareAll(start_val, .lte, end_val, Type.usize))) {
- return sema.fail(
+ if (try sema.resolveDefinedValue(block, end_src, end)) |end_val| {
+ if (try sema.resolveDefinedValue(block, start_src, start)) |start_val| {
+ if (!by_length and !(try sema.compareAll(start_val, .lte, end_val, Type.usize))) {
+ return sema.fail(
+ block,
+ start_src,
+ "start index {} is larger than end index {}",
+ .{
+ start_val.fmtValue(Type.usize, mod),
+ end_val.fmtValue(Type.usize, mod),
+ },
+ );
+ }
+ if (try sema.resolveMaybeUndefVal(new_ptr)) |ptr_val| sentinel_check: {
+ const expected_sentinel = sentinel orelse break :sentinel_check;
+ const start_int = start_val.getUnsignedInt(sema.mod.getTarget()).?;
+ const end_int = end_val.getUnsignedInt(sema.mod.getTarget()).?;
+ const sentinel_index = try sema.usizeCast(block, end_src, end_int - start_int);
+
+ const elem_ptr = try ptr_val.elemPtr(sema.typeOf(new_ptr), sema.arena, sentinel_index, sema.mod);
+ const res = try sema.pointerDerefExtra(block, src, elem_ptr, elem_ty, false);
+ const actual_sentinel = switch (res) {
+ .runtime_load => break :sentinel_check,
+ .val => |v| v,
+ .needed_well_defined => |ty| return sema.fail(
block,
- start_src,
- "start index {} is larger than end index {}",
- .{
- start_val.fmtValue(Type.usize, mod),
- end_val.fmtValue(Type.usize, mod),
- },
- );
- }
- if (try sema.resolveMaybeUndefVal(new_ptr)) |ptr_val| sentinel_check: {
- const expected_sentinel = sentinel orelse break :sentinel_check;
- const start_int = start_val.getUnsignedInt(sema.mod.getTarget()).?;
- const end_int = end_val.getUnsignedInt(sema.mod.getTarget()).?;
- const sentinel_index = try sema.usizeCast(block, end_src, end_int - start_int);
-
- const elem_ptr = try ptr_val.elemPtr(sema.typeOf(new_ptr), sema.arena, sentinel_index, sema.mod);
- const res = try sema.pointerDerefExtra(block, src, elem_ptr, elem_ty, false);
- const actual_sentinel = switch (res) {
- .runtime_load => break :sentinel_check,
- .val => |v| v,
- .needed_well_defined => |ty| return sema.fail(
- block,
- src,
- "comptime dereference requires '{}' to have a well-defined layout, but it does not.",
- .{ty.fmt(sema.mod)},
- ),
- .out_of_bounds => |ty| return sema.fail(
- block,
- end_src,
- "slice end index {d} exceeds bounds of containing decl of type '{}'",
- .{ end_int, ty.fmt(sema.mod) },
- ),
- };
+ src,
+ "comptime dereference requires '{}' to have a well-defined layout, but it does not.",
+ .{ty.fmt(sema.mod)},
+ ),
+ .out_of_bounds => |ty| return sema.fail(
+ block,
+ end_src,
+ "slice end index {d} exceeds bounds of containing decl of type '{}'",
+ .{ end_int, ty.fmt(sema.mod) },
+ ),
+ };
- if (!actual_sentinel.eql(expected_sentinel, elem_ty, sema.mod)) {
- const msg = msg: {
- const msg = try sema.errMsg(block, src, "value in memory does not match slice sentinel", .{});
- errdefer msg.destroy(sema.gpa);
- try sema.errNote(block, src, msg, "expected '{}', found '{}'", .{
- expected_sentinel.fmtValue(elem_ty, sema.mod),
- actual_sentinel.fmtValue(elem_ty, sema.mod),
- });
+ if (!actual_sentinel.eql(expected_sentinel, elem_ty, sema.mod)) {
+ const msg = msg: {
+ const msg = try sema.errMsg(block, src, "value in memory does not match slice sentinel", .{});
+ errdefer msg.destroy(sema.gpa);
+ try sema.errNote(block, src, msg, "expected '{}', found '{}'", .{
+ expected_sentinel.fmtValue(elem_ty, sema.mod),
+ actual_sentinel.fmtValue(elem_ty, sema.mod),
+ });
- break :msg msg;
- };
- return sema.failWithOwnedErrorMsg(msg);
- }
+ break :msg msg;
+ };
+ return sema.failWithOwnedErrorMsg(msg);
}
}
}
+ }
- if (block.wantSafety() and !block.is_comptime) {
- // requirement: start <= end
- try sema.panicStartLargerThanEnd(block, start, end);
- }
+ if (!by_length and block.wantSafety() and !block.is_comptime) {
+ // requirement: start <= end
+ try sema.panicStartLargerThanEnd(block, start, end);
}
const new_len = if (by_length)
try sema.coerce(block, Type.usize, uncasted_end_opt, end_src)
src/Zir.zig
@@ -570,7 +570,7 @@ pub const Inst = struct {
/// Returns a pointer to the subslice.
/// Uses the `pl_node` field. AST node is the slice syntax. Payload is `SliceSentinel`.
slice_sentinel,
- /// Slice operation `array_ptr[start..][0..len]`. No sentinel.
+ /// Slice operation `array_ptr[start..][0..len]`. Optional sentinel.
/// Returns a pointer to the subslice.
/// Uses the `pl_node` field. AST node is the slice syntax. Payload is `SliceLength`.
slice_length,
@@ -2991,6 +2991,7 @@ pub const Inst = struct {
lhs: Ref,
start: Ref,
len: Ref,
+ sentinel: Ref,
start_src_node_offset: i32,
};