From fdedd62365b5e3f3fa908ae063df86d11a3c02bb Mon Sep 17 00:00:00 2001 From: Jacob Young Date: Fri, 2 Dec 2022 19:54:00 -0500 Subject: [PATCH] cbe: use memcpy for underaligned loads and stores --- src/codegen/c.zig | 37 +++++++++++++++++++++--------------- test/behavior/basic.zig | 2 -- test/behavior/bitreverse.zig | 1 - test/behavior/byteswap.zig | 1 - test/behavior/math.zig | 1 - test/behavior/ptrcast.zig | 1 - test/behavior/struct.zig | 1 - test/behavior/vector.zig | 7 ------- 8 files changed, 22 insertions(+), 29 deletions(-) diff --git a/src/codegen/c.zig b/src/codegen/c.zig index d7aec355e9..ac111cda4e 100644 --- a/src/codegen/c.zig +++ b/src/codegen/c.zig @@ -2999,30 +2999,31 @@ fn airArg(f: *Function) CValue { fn airLoad(f: *Function, inst: Air.Inst.Index) !CValue { const ty_op = f.air.instructions.items(.data)[inst].ty_op; const ptr_info = f.air.typeOf(ty_op.operand).ptrInfo().data; + const src_ty = ptr_info.pointee_type; - const inst_ty = f.air.typeOfIndex(inst); - if (!inst_ty.hasRuntimeBitsIgnoreComptime() or + if (!src_ty.hasRuntimeBitsIgnoreComptime() or !ptr_info.@"volatile" and f.liveness.isUnused(inst)) return CValue.none; const target = f.object.dg.module.getTarget(); - const is_array = lowersToArray(inst_ty, target); + const is_aligned = ptr_info.@"align" == 0 or ptr_info.@"align" >= src_ty.abiAlignment(target); + const is_array = lowersToArray(src_ty, target); + const need_memcpy = !is_aligned or is_array; const operand = try f.resolveInst(ty_op.operand); const writer = f.object.writer(); - // We need to separately initialize arrays with a memcpy so they must be mutable. - const local = try f.allocLocal(inst_ty, if (is_array) .Mut else .Const); + // We need to initialize arrays and unaligned loads with a memcpy so they must be mutable. + const local = try f.allocLocal(src_ty, if (need_memcpy) .Mut else .Const); - if (is_array) { - // Insert a memcpy to initialize this array. The source operand is always a pointer - // and thus we only need to know size/type information from the local type/dest. + if (need_memcpy) { try writer.writeAll(";\n"); try writer.writeAll("memcpy("); + if (!is_array) try writer.writeByte('&'); try f.writeCValue(writer, local, .FunctionArgument); - try writer.writeAll(", "); - try f.writeCValue(writer, operand, .FunctionArgument); + try writer.writeAll(", (const char *)"); + try f.writeCValue(writer, operand, .Other); try writer.writeAll(", sizeof("); - try f.renderTypecast(writer, inst_ty); + try f.renderTypecast(writer, src_ty); try writer.writeAll("))"); } else if (ptr_info.host_size != 0) { var host_pl = Type.Payload.Bits{ @@ -3045,12 +3046,12 @@ fn airLoad(f: *Function, inst: Air.Inst.Index) !CValue { var field_pl = Type.Payload.Bits{ .base = .{ .tag = .int_unsigned }, - .data = @intCast(u16, inst_ty.bitSize(target)), + .data = @intCast(u16, src_ty.bitSize(target)), }; const field_ty = Type.initPayload(&field_pl.base); try writer.writeAll(" = ("); - try f.renderTypecast(writer, inst_ty); + try f.renderTypecast(writer, src_ty); try writer.writeAll(")zig_wrap_"); try f.object.dg.renderTypeForBuiltinFnName(writer, field_ty); try writer.writeAll("(("); @@ -3226,8 +3227,13 @@ fn airStore(f: *Function, inst: Air.Inst.Index) !CValue { return try airStoreUndefined(f, ptr_info.pointee_type, ptr_val); const target = f.object.dg.module.getTarget(); + const is_aligned = ptr_info.@"align" == 0 or + ptr_info.@"align" >= ptr_info.pointee_type.abiAlignment(target); + const is_array = lowersToArray(ptr_info.pointee_type, target); + const need_memcpy = !is_aligned or is_array; const writer = f.object.writer(); - if (lowersToArray(ptr_info.pointee_type, target)) { + + if (need_memcpy) { // For this memcpy to safely work we need the rhs to have the same // underlying type as the lhs (i.e. they must both be arrays of the same underlying type). assert(src_ty.eql(ptr_info.pointee_type, f.object.dg.module)); @@ -3244,9 +3250,10 @@ fn airStore(f: *Function, inst: Air.Inst.Index) !CValue { break :blk new_local; } else src_val; - try writer.writeAll("memcpy("); + try writer.writeAll("memcpy((char *)"); try f.writeCValue(writer, ptr_val, .FunctionArgument); try writer.writeAll(", "); + if (!is_array) try writer.writeByte('&'); try f.writeCValue(writer, array_src, .FunctionArgument); try writer.writeAll(", sizeof("); try f.renderTypecast(writer, src_ty); diff --git a/test/behavior/basic.zig b/test/behavior/basic.zig index 9fd9e03116..9f6dac81ca 100644 --- a/test/behavior/basic.zig +++ b/test/behavior/basic.zig @@ -754,7 +754,6 @@ fn maybe(x: bool) anyerror!?u32 { } test "pointer to thread local array" { - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO @@ -770,7 +769,6 @@ threadlocal var buffer: [11]u8 = undefined; test "auto created variables have correct alignment" { if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO const S = struct { fn foo(str: [*]const u8) u32 { diff --git a/test/behavior/bitreverse.zig b/test/behavior/bitreverse.zig index 092f3a1fed..d834f09cae 100644 --- a/test/behavior/bitreverse.zig +++ b/test/behavior/bitreverse.zig @@ -155,7 +155,6 @@ fn vector0() !void { test "bitReverse vectors u0" { if (builtin.zig_backend == .stage1) return error.SkipZigTest; if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; comptime try vector0(); diff --git a/test/behavior/byteswap.zig b/test/behavior/byteswap.zig index 5313b612b0..8de75a572c 100644 --- a/test/behavior/byteswap.zig +++ b/test/behavior/byteswap.zig @@ -121,7 +121,6 @@ fn vector0() !void { test "@byteSwap vectors u0" { if (builtin.zig_backend == .stage1) return error.SkipZigTest; if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; comptime try vector0(); diff --git a/test/behavior/math.zig b/test/behavior/math.zig index 4b6b882fe5..40337d041a 100644 --- a/test/behavior/math.zig +++ b/test/behavior/math.zig @@ -1518,7 +1518,6 @@ fn testRound(comptime T: type, x: T) !void { } test "vector integer addition" { - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO diff --git a/test/behavior/ptrcast.zig b/test/behavior/ptrcast.zig index 79f75e0131..256a64c67b 100644 --- a/test/behavior/ptrcast.zig +++ b/test/behavior/ptrcast.zig @@ -78,7 +78,6 @@ fn testReinterpretBytesAsExternStruct() !void { test "reinterpret bytes of an extern struct (with under-aligned fields) into another" { if (builtin.zig_backend == .stage1) return error.SkipZigTest; - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO: Under-aligned fields are not yet supported in the CBE try testReinterpretExternStructAsExternStruct(); comptime try testReinterpretExternStructAsExternStruct(); diff --git a/test/behavior/struct.zig b/test/behavior/struct.zig index a74b9fdd53..2340e364d1 100644 --- a/test/behavior/struct.zig +++ b/test/behavior/struct.zig @@ -641,7 +641,6 @@ test "default struct initialization fields" { test "packed array 24bits" { if (builtin.zig_backend == .stage1) return error.SkipZigTest; - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; diff --git a/test/behavior/vector.zig b/test/behavior/vector.zig index 30dd563abe..0dedcc2505 100644 --- a/test/behavior/vector.zig +++ b/test/behavior/vector.zig @@ -75,7 +75,6 @@ test "vector bin compares with mem.eql" { test "vector int operators" { if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO @@ -139,7 +138,6 @@ test "vector bit operators" { test "implicit cast vector to array" { if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO @@ -158,7 +156,6 @@ test "implicit cast vector to array" { test "array to vector" { if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO @@ -177,7 +174,6 @@ test "array to vector" { test "tuple to vector" { if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO @@ -210,7 +206,6 @@ test "tuple to vector" { test "vector casts of sizes not divisible by 8" { if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO @@ -945,7 +940,6 @@ test "multiplication-assignment operator with an array operand" { return error.SkipZigTest; } if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO @@ -1194,7 +1188,6 @@ test "zero divisor" { test "zero multiplicand" { if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO - if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO