From 09c7d5aebc4f7fe96a89f93c0cf99cc03977ea5f Mon Sep 17 00:00:00 2001 From: Robin Voetter Date: Thu, 21 Oct 2021 16:17:21 +0200 Subject: stage2: elemPtr for slices * Restructure elemPtr a bit * New AIR instruction: slice_elem_ptr, which returns a pointer to an element of a slice * Value: adapt elemPtr to work on slices --- src/codegen/c.zig | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'src/codegen/c.zig') diff --git a/src/codegen/c.zig b/src/codegen/c.zig index f09bb574af..9050499fce 100644 --- a/src/codegen/c.zig +++ b/src/codegen/c.zig @@ -1083,6 +1083,7 @@ fn genBody(f: *Function, body: []const Air.Inst.Index) error{ AnalysisFail, OutO .ptr_elem_val => try airPtrElemVal(f, inst, "["), .ptr_elem_ptr => try airPtrElemPtr(f, inst), .slice_elem_val => try airSliceElemVal(f, inst, "["), + .slice_elem_ptr => try airSliceElemPtr(f, inst), .array_elem_val => try airArrayElemVal(f, inst), .unwrap_errunion_payload => try airUnwrapErrUnionPay(f, inst), @@ -1165,6 +1166,24 @@ fn airSliceElemVal(f: *Function, inst: Air.Inst.Index, prefix: []const u8) !CVal return local; } +fn airSliceElemPtr(f: *Function, inst: Air.Inst.Index) !CValue { + if (f.liveness.isUnused(inst)) + return CValue.none; + const ty_pl = f.air.instructions.items(.data)[inst].ty_pl; + const bin_op = f.air.extraData(Air.Bin, ty_pl.payload).data; + + const slice = try f.resolveInst(bin_op.lhs); + const index = try f.resolveInst(bin_op.rhs); + const writer = f.object.writer(); + const local = try f.allocLocal(f.air.typeOfIndex(inst), .Const); + try writer.writeAll(" = &"); + try f.writeCValue(writer, slice); + try writer.writeByte('['); + try f.writeCValue(writer, index); + try writer.writeAll("];\n"); + return local; +} + fn airArrayElemVal(f: *Function, inst: Air.Inst.Index) !CValue { if (f.liveness.isUnused(inst)) return CValue.none; -- cgit v1.2.3