authorgravatar for joachim.schmidt557@outlook.comJoachim Schmidt <joachim.schmidt557@outlook.com> 2022-03-29 20:19:25+02:00
committergravatar for joachim.schmidt557@outlook.comJoachim Schmidt <joachim.schmidt557@outlook.com> 2022-04-01 22:02:56+02:00
log37a8c28802b418718487995a1fa6000b0aab8a84
tree43bd579cfe5949c50d48f8b2625d8defa7917a24
parent7285f0557cbc26893a7a64f345432ad01981180c
signaturelock-open Commit is signed but in an unrecognized format.

stage2 ARM: implement add/sub_with_overflow for ints < 32 bits


2 files changed, 34 insertions(+), 3 deletions(-)

src/arch/arm/CodeGen.zig+34-1
...@@ -1361,13 +1361,46 @@ fn airOverflow(self: *Self, inst: Air.Inst.Index) !void {...@@ -1361,13 +1361,46 @@ fn airOverflow(self: *Self, inst: Air.Inst.Index) !void {
1361 const lhs_ty = self.air.typeOf(extra.lhs);1361 const lhs_ty = self.air.typeOf(extra.lhs);
1362 const rhs_ty = self.air.typeOf(extra.rhs);1362 const rhs_ty = self.air.typeOf(extra.rhs);
13631363
1364 const tuple_ty = self.air.typeOfIndex(inst);
1365 const tuple_size = @intCast(u32, tuple_ty.abiSize(self.target.*));
1366 const tuple_align = tuple_ty.abiAlignment(self.target.*);
1367 const overflow_bit_offset = @intCast(u32, tuple_ty.structFieldOffset(1, self.target.*));
1368
1364 switch (lhs_ty.zigTypeTag()) {1369 switch (lhs_ty.zigTypeTag()) {
1365 .Vector => return self.fail("TODO implement add_with_overflow/sub_with_overflow for vectors", .{}),1370 .Vector => return self.fail("TODO implement add_with_overflow/sub_with_overflow for vectors", .{}),
1366 .Int => {1371 .Int => {
1367 assert(lhs_ty.eql(rhs_ty, self.target.*));1372 assert(lhs_ty.eql(rhs_ty, self.target.*));
1368 const int_info = lhs_ty.intInfo(self.target.*);1373 const int_info = lhs_ty.intInfo(self.target.*);
1369 if (int_info.bits < 32) {1374 if (int_info.bits < 32) {
1370 return self.fail("TODO ARM overflow operations on integers < u32/i32", .{});1375 const stack_offset = try self.allocMem(inst, tuple_size, tuple_align);
1376
1377 try self.spillCompareFlagsIfOccupied();
1378 self.compare_flags_inst = null;
1379
1380 const base_tag: Air.Inst.Tag = switch (tag) {
1381 .add_with_overflow => .add,
1382 .sub_with_overflow => .sub,
1383 else => unreachable,
1384 };
1385 const dest = try self.binOp(base_tag, null, lhs, rhs, lhs_ty, rhs_ty);
1386 const dest_reg = dest.register;
1387 self.register_manager.freezeRegs(&.{dest_reg});
1388 defer self.register_manager.unfreezeRegs(&.{dest_reg});
1389
1390 const truncated_reg = try self.register_manager.allocReg(null);
1391 self.register_manager.freezeRegs(&.{truncated_reg});
1392 defer self.register_manager.unfreezeRegs(&.{truncated_reg});
1393
1394 // sbfx/ubfx truncated, dest, #0, #bits
1395 try self.truncRegister(dest_reg, truncated_reg, int_info.signedness, int_info.bits);
1396
1397 // cmp dest, truncated
1398 _ = try self.binOp(.cmp_eq, null, dest, .{ .register = truncated_reg }, Type.usize, Type.usize);
1399
1400 try self.genSetStack(lhs_ty, stack_offset, .{ .register = truncated_reg });
1401 try self.genSetStack(Type.initTag(.u1), stack_offset - overflow_bit_offset, .{ .compare_flags_unsigned = .neq });
1402
1403 break :result MCValue{ .stack_offset = stack_offset };
1371 } else if (int_info.bits == 32) {1404 } else if (int_info.bits == 32) {
1372 // Only say yes if the operation is1405 // Only say yes if the operation is
1373 // commutative, i.e. we can swap both of the1406 // commutative, i.e. we can swap both of the
test/behavior/math.zig-2
...@@ -635,7 +635,6 @@ test "128-bit multiplication" {...@@ -635,7 +635,6 @@ test "128-bit multiplication" {
635test "@addWithOverflow" {635test "@addWithOverflow" {
636 if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO636 if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
637 if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO637 if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
638 if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
639638
640 var result: u8 = undefined;639 var result: u8 = undefined;
641 try expect(@addWithOverflow(u8, 250, 100, &result));640 try expect(@addWithOverflow(u8, 250, 100, &result));
...@@ -700,7 +699,6 @@ test "@mulWithOverflow" {...@@ -700,7 +699,6 @@ test "@mulWithOverflow" {
700test "@subWithOverflow" {699test "@subWithOverflow" {
701 if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO700 if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
702 if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO701 if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
703 if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
704702
705 var result: u8 = undefined;703 var result: u8 = undefined;
706 try expect(@subWithOverflow(u8, 1, 2, &result));704 try expect(@subWithOverflow(u8, 1, 2, &result));