Commit 293d6bdc73

Andrew Kelley <andrew@ziglang.org>
2023-02-18 00:39:45
AstGen: back to index-based for loops
1 parent 841add6
src/AstGen.zig
@@ -88,7 +88,6 @@ fn setExtra(astgen: *AstGen, index: usize, extra: anytype) void {
             Zir.Inst.BuiltinCall.Flags => @bitCast(u32, @field(extra, field.name)),
             Zir.Inst.SwitchBlock.Bits => @bitCast(u32, @field(extra, field.name)),
             Zir.Inst.FuncFancy.Bits => @bitCast(u32, @field(extra, field.name)),
-            Zir.Inst.ElemPtrImm.Bits => @bitCast(u32, @field(extra, field.name)),
             else => @compileError("bad field type"),
         };
         i += 1;
@@ -1566,9 +1565,7 @@ fn arrayInitExprRlPtrInner(
     for (elements) |elem_init, i| {
         const elem_ptr = try gz.addPlNode(.elem_ptr_imm, elem_init, Zir.Inst.ElemPtrImm{
             .ptr = result_ptr,
-            .bits = .{
-                .index = @intCast(u31, i),
-            },
+            .index = @intCast(u32, i),
         });
         astgen.extra.items[extra_index] = refToIndex(elem_ptr).?;
         extra_index += 1;
@@ -2601,6 +2598,7 @@ fn addEnsureResult(gz: *GenZir, maybe_unused_result: Zir.Inst.Ref, statement: As
             .field_base_ptr,
             .ret_ptr,
             .ret_type,
+            .for_len,
             .@"try",
             .try_ptr,
             //.try_inline,
@@ -2669,7 +2667,6 @@ fn addEnsureResult(gz: *GenZir, maybe_unused_result: Zir.Inst.Ref, statement: As
             .validate_deref,
             .save_err_ret_index,
             .restore_err_ret_index,
-            .for_check_lens,
             => break :b true,
 
             .@"defer" => unreachable,
@@ -6305,23 +6302,26 @@ fn forExpr(
     const node_data = tree.nodes.items(.data);
     const gpa = astgen.gpa;
 
-    const allocs = try gpa.alloc(Zir.Inst.Ref, for_full.ast.inputs.len);
-    defer gpa.free(allocs);
+    // For counters, this is the start value; for indexables, this is the base
+    // pointer that can be used with elem_ptr and similar instructions.
+    // Special value `none` means that this is a counter and its start value is
+    // zero, indicating that the main index counter can be used directly.
+    const indexables = try gpa.alloc(Zir.Inst.Ref, for_full.ast.inputs.len);
+    defer gpa.free(indexables);
     // elements of this array can be `none`, indicating no length check.
     const lens = try gpa.alloc(Zir.Inst.Ref, for_full.ast.inputs.len);
     defer gpa.free(lens);
 
-    const alloc_tag: Zir.Inst.Tag = if (is_inline) .alloc_comptime_mut else .alloc_mut;
+    // We will use a single zero-based counter no matter how many indexables there are.
+    const index_ptr = blk: {
+        const alloc_tag: Zir.Inst.Tag = if (is_inline) .alloc_comptime_mut else .alloc;
+        const index_ptr = try parent_gz.addUnNode(alloc_tag, .usize_type, node);
+        // initialize to zero
+        _ = try parent_gz.addBin(.store, index_ptr, .zero_usize);
+        break :blk index_ptr;
+    };
 
-    // Tracks the index of allocs/lens that has a length to be checked and is
-    // used for the end value.
-    // If this is null, there are no len checks.
-    var end_input_index: ?u32 = null;
-    // This is a value to use to find out if the for loop has reached the end
-    // yet. It prefers to use a counter since the end value is provided directly,
-    // and otherwise falls back to adding ptr+len of a slice to compute end.
-    // Corresponds to end_input_index and will be .none in case that value is null.
-    var cond_end_val: Zir.Inst.Ref = .none;
+    var any_len_checks = false;
 
     {
         var capture_token = for_full.payload_token;
@@ -6341,10 +6341,8 @@ fn forExpr(
                 if (capture_is_ref) {
                     return astgen.failTok(ident_tok, "cannot capture reference to range", .{});
                 }
-                const counter_ptr = try parent_gz.addUnNode(alloc_tag, .usize_type, node);
                 const start_node = node_data[input].lhs;
                 const start_val = try expr(parent_gz, scope, .{ .rl = .none }, start_node);
-                _ = try parent_gz.addBin(.store, counter_ptr, start_val);
 
                 const end_node = node_data[input].rhs;
                 const end_val = if (end_node != 0)
@@ -6352,7 +6350,8 @@ fn forExpr(
                 else
                     .none;
 
-                const range_len = if (end_val == .none or nodeIsTriviallyZero(tree, start_node))
+                const start_is_zero = nodeIsTriviallyZero(tree, start_node);
+                const range_len = if (end_val == .none or start_is_zero)
                     end_val
                 else
                     try parent_gz.addPlNode(.sub, input, Zir.Inst.Bin{
@@ -6360,61 +6359,33 @@ fn forExpr(
                         .rhs = start_val,
                     });
 
-                if (range_len != .none and cond_end_val == .none) {
-                    end_input_index = i;
-                    cond_end_val = end_val;
-                }
-
-                allocs[i] = counter_ptr;
+                any_len_checks = any_len_checks or range_len != .none;
+                indexables[i] = if (start_is_zero) .none else start_val;
                 lens[i] = range_len;
             } else {
                 const indexable = try expr(parent_gz, scope, .{ .rl = .none }, input);
-                // This instruction has nice compile errors so we put it before the other ones
-                // even though it is not needed until later in the block.
-                const ptr_len = try parent_gz.addUnNode(.indexable_ptr_len, indexable, input);
-                const base_ptr = try parent_gz.addPlNode(.elem_ptr_imm, input, Zir.Inst.ElemPtrImm{
-                    .ptr = indexable,
-                    .bits = .{
-                        .index = 0,
-                        .manyptr = true,
-                    },
-                });
-                const alloc_ty_inst = try parent_gz.addUnNode(.typeof, base_ptr, node);
-                const alloc = try parent_gz.addUnNode(alloc_tag, alloc_ty_inst, node);
-                _ = try parent_gz.addBin(.store, alloc, base_ptr);
-
-                if (end_input_index == null) {
-                    end_input_index = i;
-                    assert(cond_end_val == .none);
-                }
+                const indexable_len = try parent_gz.addUnNode(.indexable_ptr_len, indexable, input);
 
-                allocs[i] = alloc;
-                lens[i] = ptr_len;
+                any_len_checks = true;
+                indexables[i] = indexable;
+                lens[i] = indexable_len;
             }
         }
     }
 
-    // In case there are no counters which already have an end computed, we
-    // compute an end from base pointer plus length.
-    if (end_input_index) |i| {
-        if (cond_end_val == .none) {
-            cond_end_val = try parent_gz.addPlNode(.add, for_full.ast.inputs[i], Zir.Inst.Bin{
-                .lhs = allocs[i],
-                .rhs = lens[i],
-            });
-        }
-    }
-
     // We use a dedicated ZIR instruction to assert the lengths to assist with
     // nicer error reporting as well as fewer ZIR bytes emitted.
-    if (end_input_index != null) {
+    const len: Zir.Inst.Ref = len: {
+        if (!any_len_checks) break :len .none;
+
         const lens_len = @intCast(u32, lens.len);
         try astgen.extra.ensureUnusedCapacity(gpa, @typeInfo(Zir.Inst.MultiOp).Struct.fields.len + lens_len);
-        _ = try parent_gz.addPlNode(.for_check_lens, node, Zir.Inst.MultiOp{
+        const len = try parent_gz.addPlNode(.for_len, node, Zir.Inst.MultiOp{
             .operands_len = lens_len,
         });
         appendRefsAssumeCapacity(astgen, lens);
-    }
+        break :len len;
+    };
 
     const loop_tag: Zir.Inst.Tag = if (is_inline) .block_inline else .loop;
     const loop_block = try parent_gz.makeBlockInst(loop_tag, node);
@@ -6429,22 +6400,14 @@ fn forExpr(
     var cond_scope = parent_gz.makeSubBlock(&loop_scope.base);
     defer cond_scope.unstack();
 
-    // Load all the iterables.
-    const loaded_ptrs = try gpa.alloc(Zir.Inst.Ref, allocs.len);
-    defer gpa.free(loaded_ptrs);
-    for (allocs) |alloc, i| {
-        loaded_ptrs[i] = try cond_scope.addUnNode(.load, alloc, for_full.ast.inputs[i]);
-    }
-
     // Check the condition.
-    const input_index = end_input_index orelse {
+    if (!any_len_checks) {
         return astgen.failNode(node, "TODO: handle infinite for loop", .{});
-    };
-    assert(cond_end_val != .none);
-
-    const cond = try cond_scope.addPlNode(.cmp_neq, for_full.ast.inputs[input_index], Zir.Inst.Bin{
-        .lhs = loaded_ptrs[input_index],
-        .rhs = cond_end_val,
+    }
+    const index = try cond_scope.addUnNode(.load, index_ptr, node);
+    const cond = try cond_scope.addPlNode(.cmp_lt, node, Zir.Inst.Bin{
+        .lhs = index,
+        .rhs = len,
     });
 
     const condbr_tag: Zir.Inst.Tag = if (is_inline) .condbr_inline else .condbr;
@@ -6455,14 +6418,12 @@ fn forExpr(
     // cond_block unstacked now, can add new instructions to loop_scope
     try loop_scope.instructions.append(gpa, cond_block);
 
-    // Increment the loop variables.
-    for (allocs) |alloc, i| {
-        const incremented = try loop_scope.addPlNode(.add, node, Zir.Inst.Bin{
-            .lhs = loaded_ptrs[i],
-            .rhs = .one_usize,
-        });
-        _ = try loop_scope.addBin(.store, alloc, incremented);
-    }
+    // Increment the index variable.
+    const index_plus_one = try loop_scope.addPlNode(.add, node, Zir.Inst.Bin{
+        .lhs = index,
+        .rhs = .one_usize,
+    });
+    _ = try loop_scope.addBin(.store, index_ptr, index_plus_one);
     const repeat_tag: Zir.Inst.Tag = if (is_inline) .repeat_inline else .repeat;
     _ = try loop_scope.addNode(repeat_tag, node);
 
@@ -6500,21 +6461,43 @@ fn forExpr(
             const name_str_index = try astgen.identAsString(ident_tok);
             try astgen.detectLocalShadowing(capture_sub_scope, name_str_index, ident_tok, capture_name, .capture);
 
-            const loaded = if (capture_is_ref)
-                loaded_ptrs[i]
-            else
-                try then_scope.addUnNode(.load, loaded_ptrs[i], input);
+            const capture_inst = inst: {
+                const is_counter = node_tags[input] == .for_range;
+
+                if (indexables[i] == .none) {
+                    // Special case: the main index can be used directly.
+                    assert(is_counter);
+                    assert(!capture_is_ref);
+                    break :inst index;
+                }
+
+                // For counters, we add the index variable to the start value; for
+                // indexables, we use it as an element index. This is so similar
+                // that they can share the same code paths, branching only on the
+                // ZIR tag.
+                const switch_cond = (@as(u2, @boolToInt(capture_is_ref)) << 1) | @boolToInt(is_counter);
+                const tag: Zir.Inst.Tag = switch (switch_cond) {
+                    0b00 => .elem_val,
+                    0b01 => .add,
+                    0b10 => .elem_ptr,
+                    0b11 => unreachable, // compile error emitted already
+                };
+                break :inst try then_scope.addPlNode(tag, input, Zir.Inst.Bin{
+                    .lhs = indexables[i],
+                    .rhs = index,
+                });
+            };
 
             capture_scopes[i] = .{
                 .parent = capture_sub_scope,
                 .gen_zir = &then_scope,
                 .name = name_str_index,
-                .inst = loaded,
+                .inst = capture_inst,
                 .token_src = ident_tok,
                 .id_cat = .capture,
             };
 
-            try then_scope.addDbgVar(.dbg_var_val, name_str_index, loaded);
+            try then_scope.addDbgVar(.dbg_var_val, name_str_index, capture_inst);
             capture_sub_scope = &capture_scopes[i].base;
         }
 
src/print_zir.zig
@@ -355,7 +355,7 @@ const Writer = struct {
             .array_type,
             => try self.writePlNodeBin(stream, inst),
 
-            .for_check_lens => try self.writePlNodeMultiOp(stream, inst),
+            .for_len => try self.writePlNodeMultiOp(stream, inst),
 
             .elem_ptr_imm => try self.writeElemPtrImm(stream, inst),
 
@@ -888,9 +888,7 @@ const Writer = struct {
         const extra = self.code.extraData(Zir.Inst.ElemPtrImm, inst_data.payload_index).data;
 
         try self.writeInstRef(stream, extra.ptr);
-        try stream.print(", {d}", .{extra.bits.index});
-        try self.writeFlag(stream, ", manyptr", extra.bits.manyptr);
-        try stream.writeAll(") ");
+        try stream.print(", {d}) ", .{extra.index});
         try self.writeSrc(stream, inst_data.src());
     }
 
src/Sema.zig
@@ -1035,6 +1035,7 @@ fn analyzeBodyInner(
             .@"await"                     => try sema.zirAwait(block, inst),
             .array_base_ptr               => try sema.zirArrayBasePtr(block, inst),
             .field_base_ptr               => try sema.zirFieldBasePtr(block, inst),
+            .for_len                      => try sema.zirForLen(block, inst),
 
             .clz       => try sema.zirBitCount(block, inst, .clz,      Value.clz),
             .ctz       => try sema.zirBitCount(block, inst, .ctz,      Value.ctz),
@@ -1386,11 +1387,6 @@ fn analyzeBodyInner(
                 i += 1;
                 continue;
             },
-            .for_check_lens => {
-                try sema.zirForCheckLens(block, inst);
-                i += 1;
-                continue;
-            },
 
             // Special case instructions to handle comptime control flow.
             .@"break" => {
@@ -3924,6 +3920,16 @@ fn zirFieldBasePtr(
     return sema.failWithStructInitNotSupported(block, src, sema.typeOf(start_ptr).childType());
 }
 
+fn zirForLen(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.Inst.Ref {
+    const inst_data = sema.code.instructions.items(.data)[inst].pl_node;
+    const extra = sema.code.extraData(Zir.Inst.MultiOp, inst_data.payload_index);
+    const args = sema.code.refSlice(extra.end, extra.data.operands_len);
+    const src = inst_data.src();
+
+    _ = args;
+    return sema.fail(block, src, "TODO implement zirForCheckLens", .{});
+}
+
 fn validateArrayInitTy(
     sema: *Sema,
     block: *Block,
@@ -9649,7 +9655,7 @@ fn zirElemPtr(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
     const extra = sema.code.extraData(Zir.Inst.Bin, inst_data.payload_index).data;
     const array_ptr = try sema.resolveInst(extra.lhs);
     const elem_index = try sema.resolveInst(extra.rhs);
-    return sema.elemPtr(block, src, array_ptr, elem_index, src, false, .One);
+    return sema.elemPtr(block, src, array_ptr, elem_index, src, false);
 }
 
 fn zirElemPtrNode(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.Inst.Ref {
@@ -9662,7 +9668,7 @@ fn zirElemPtrNode(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError
     const extra = sema.code.extraData(Zir.Inst.Bin, inst_data.payload_index).data;
     const array_ptr = try sema.resolveInst(extra.lhs);
     const elem_index = try sema.resolveInst(extra.rhs);
-    return sema.elemPtr(block, src, array_ptr, elem_index, elem_index_src, false, .One);
+    return sema.elemPtr(block, src, array_ptr, elem_index, elem_index_src, false);
 }
 
 fn zirElemPtrImm(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.Inst.Ref {
@@ -9673,9 +9679,8 @@ fn zirElemPtrImm(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!
     const src = inst_data.src();
     const extra = sema.code.extraData(Zir.Inst.ElemPtrImm, inst_data.payload_index).data;
     const array_ptr = try sema.resolveInst(extra.ptr);
-    const elem_index = try sema.addIntUnsigned(Type.usize, extra.bits.index);
-    const size: std.builtin.Type.Pointer.Size = if (extra.bits.manyptr) .Many else .One;
-    return sema.elemPtr(block, src, array_ptr, elem_index, src, true, size);
+    const elem_index = try sema.addIntUnsigned(Type.usize, extra.index);
+    return sema.elemPtr(block, src, array_ptr, elem_index, src, true);
 }
 
 fn zirSliceStart(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.Inst.Ref {
@@ -17102,16 +17107,6 @@ fn zirRestoreErrRetIndex(sema: *Sema, start_block: *Block, inst: Zir.Inst.Index)
     return sema.popErrorReturnTrace(start_block, src, operand, saved_index);
 }
 
-fn zirForCheckLens(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!void {
-    const inst_data = sema.code.instructions.items(.data)[inst].pl_node;
-    const extra = sema.code.extraData(Zir.Inst.MultiOp, inst_data.payload_index);
-    const args = sema.code.refSlice(extra.end, extra.data.operands_len);
-    const src = inst_data.src();
-
-    _ = args;
-    return sema.fail(block, src, "TODO implement zirForCheckLens", .{});
-}
-
 fn addToInferredErrorSet(sema: *Sema, uncasted_operand: Air.Inst.Ref) !void {
     assert(sema.fn_ret_ty.zigTypeTag() == .ErrorUnion);
 
@@ -22906,7 +22901,7 @@ fn panicSentinelMismatch(
     const actual_sentinel = if (ptr_ty.isSlice())
         try parent_block.addBinOp(.slice_elem_val, ptr, sentinel_index)
     else blk: {
-        const elem_ptr_ty = try sema.elemPtrType(ptr_ty, null, .One);
+        const elem_ptr_ty = try sema.elemPtrType(ptr_ty, null);
         const sentinel_ptr = try parent_block.addPtrElemPtr(ptr, sentinel_index, elem_ptr_ty);
         break :blk try parent_block.addTyOp(.load, sentinel_ty, sentinel_ptr);
     };
@@ -24073,7 +24068,6 @@ fn elemPtr(
     elem_index: Air.Inst.Ref,
     elem_index_src: LazySrcLoc,
     init: bool,
-    size: std.builtin.Type.Pointer.Size,
 ) CompileError!Air.Inst.Ref {
     const indexable_ptr_src = src; // TODO better source location
     const indexable_ptr_ty = sema.typeOf(indexable_ptr);
@@ -24100,12 +24094,13 @@ fn elemPtr(
                         const index_val = maybe_index_val orelse break :rs elem_index_src;
                         const index = @intCast(usize, index_val.toUnsignedInt(target));
                         const elem_ptr = try ptr_val.elemPtr(indexable_ty, sema.arena, index, sema.mod);
-                        const elem_ptr_ty = try sema.elemPtrType(indexable_ty, index, size);
-                        return sema.addConstant(elem_ptr_ty, elem_ptr);
+                        const result_ty = try sema.elemPtrType(indexable_ty, index);
+                        return sema.addConstant(result_ty, elem_ptr);
                     };
-                    const elem_ptr_ty = try sema.elemPtrType(indexable_ty, null, size);
+                    const result_ty = try sema.elemPtrType(indexable_ty, null);
+
                     try sema.requireRuntimeBlock(block, src, runtime_src);
-                    return block.addPtrElemPtr(indexable, elem_index, elem_ptr_ty);
+                    return block.addPtrElemPtr(indexable, elem_index, result_ty);
                 },
                 .One => {
                     assert(indexable_ty.childType().zigTypeTag() == .Array); // Guaranteed by isIndexable
@@ -24167,7 +24162,7 @@ fn elemVal(
             },
             .One => {
                 assert(indexable_ty.childType().zigTypeTag() == .Array); // Guaranteed by isIndexable
-                const elem_ptr = try sema.elemPtr(block, indexable_src, indexable, elem_index, elem_index_src, false, .One);
+                const elem_ptr = try sema.elemPtr(block, indexable_src, indexable, elem_index, elem_index_src, false);
                 return sema.analyzeLoad(block, indexable_src, elem_ptr, elem_index_src);
             },
         },
@@ -24405,7 +24400,7 @@ fn elemPtrArray(
         break :o index;
     } else null;
 
-    const elem_ptr_ty = try sema.elemPtrType(array_ptr_ty, offset, .One);
+    const elem_ptr_ty = try sema.elemPtrType(array_ptr_ty, offset);
 
     if (maybe_undef_array_ptr_val) |array_ptr_val| {
         if (array_ptr_val.isUndef()) {
@@ -24510,7 +24505,7 @@ fn elemPtrSlice(
         break :o index;
     } else null;
 
-    const elem_ptr_ty = try sema.elemPtrType(slice_ty, offset, .One);
+    const elem_ptr_ty = try sema.elemPtrType(slice_ty, offset);
 
     if (maybe_undef_slice_val) |slice_val| {
         if (slice_val.isUndef()) {
@@ -26240,7 +26235,7 @@ fn storePtr2(
             const elem_src = operand_src; // TODO better source location
             const elem = try sema.tupleField(block, operand_src, uncasted_operand, elem_src, i);
             const elem_index = try sema.addIntUnsigned(Type.usize, i);
-            const elem_ptr = try sema.elemPtr(block, ptr_src, ptr, elem_index, elem_src, false, .One);
+            const elem_ptr = try sema.elemPtr(block, ptr_src, ptr, elem_index, elem_src, false);
             try sema.storePtr2(block, src, elem_ptr, elem_src, elem, elem_src, .store);
         }
         return;
@@ -33277,12 +33272,7 @@ fn compareVector(
 /// For []T, returns *T
 /// Handles const-ness and address spaces in particular.
 /// This code is duplicated in `analyzePtrArithmetic`.
-fn elemPtrType(
-    sema: *Sema,
-    ptr_ty: Type,
-    offset: ?usize,
-    size: std.builtin.Type.Pointer.Size,
-) !Type {
+fn elemPtrType(sema: *Sema, ptr_ty: Type, offset: ?usize) !Type {
     const ptr_info = ptr_ty.ptrInfo().data;
     const elem_ty = ptr_ty.elemType2();
     const allow_zero = ptr_info.@"allowzero" and (offset orelse 0) == 0;
@@ -33327,7 +33317,6 @@ fn elemPtrType(
         break :a new_align;
     };
     return try Type.ptr(sema.arena, sema.mod, .{
-        .size = size,
         .pointee_type = elem_ty,
         .mutable = ptr_info.mutable,
         .@"addrspace" = ptr_info.@"addrspace",
src/Zir.zig
@@ -79,7 +79,6 @@ pub fn extraData(code: Zir, comptime T: type, index: usize) struct { data: T, en
             Inst.BuiltinCall.Flags => @bitCast(Inst.BuiltinCall.Flags, code.extra[i]),
             Inst.SwitchBlock.Bits => @bitCast(Inst.SwitchBlock.Bits, code.extra[i]),
             Inst.FuncFancy.Bits => @bitCast(Inst.FuncFancy.Bits, code.extra[i]),
-            Inst.ElemPtrImm.Bits => @bitCast(Inst.ElemPtrImm.Bits, code.extra[i]),
             else => @compileError("bad field type"),
         };
         i += 1;
@@ -501,14 +500,14 @@ pub const Inst = struct {
         /// Uses the `node` field.
         repeat_inline,
         /// Asserts that all the lengths provided match. Used to build a for loop.
-        /// Return value is always void.
+        /// Return value is the length as a usize.
         /// Uses the `pl_node` field with payload `MultiOp`.
         /// There is exactly one item corresponding to each AST node inside the for
-        /// loop condition. Each item may be `none`, indicating an unbounded range.
+        /// loop condition. Any item may be `none`, indicating an unbounded range.
         /// Illegal behaviors:
         ///  * If all lengths are unbounded ranges (always a compile error).
         ///  * If any two lengths do not match each other.
-        for_check_lens,
+        for_len,
         /// Merge two error sets into one, `E1 || E2`.
         /// Uses the `pl_node` field with payload `Bin`.
         merge_error_sets,
@@ -1254,7 +1253,7 @@ pub const Inst = struct {
                 .defer_err_code,
                 .save_err_ret_index,
                 .restore_err_ret_index,
-                .for_check_lens,
+                .for_len,
                 => false,
 
                 .@"break",
@@ -1322,7 +1321,6 @@ pub const Inst = struct {
                 .memcpy,
                 .memset,
                 .check_comptime_control_flow,
-                .for_check_lens,
                 .@"defer",
                 .defer_err_code,
                 .restore_err_ret_index,
@@ -1547,6 +1545,7 @@ pub const Inst = struct {
                 .repeat_inline,
                 .panic,
                 .panic_comptime,
+                .for_len,
                 .@"try",
                 .try_ptr,
                 //.try_inline,
@@ -1602,7 +1601,7 @@ pub const Inst = struct {
                 .@"break" = .@"break",
                 .break_inline = .@"break",
                 .check_comptime_control_flow = .un_node,
-                .for_check_lens = .pl_node,
+                .for_len = .pl_node,
                 .call = .pl_node,
                 .cmp_lt = .pl_node,
                 .cmp_lte = .pl_node,
@@ -2975,13 +2974,7 @@ pub const Inst = struct {
 
     pub const ElemPtrImm = struct {
         ptr: Ref,
-        bits: Bits,
-
-        pub const Bits = packed struct(u32) {
-            index: u31,
-            /// Controls whether the type returned is `*T` or `[*]T`.
-            manyptr: bool = false,
-        };
+        index: u32,
     };
 
     /// 0. multi_cases_len: u32 // If has_multi_cases is set.