authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2022-03-23 19:58:13-07:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2022-03-23 19:58:13-07:00
logaca42c62598523b92de7a51d3d84f2f2e5146536
tree18914e86afb1bfcbbd940198087e2c30782eecea
parent74ccd0c40b6871093f52769d342c1316e9ded0c0

Sema: fix comptime elem_ptr compare fixed address

2 files changed, 30 insertions(+), 5 deletions(-)

src/value.zig+28-2
......@@ -1008,7 +1008,7 @@ pub const Value = extern union {
10081008 space: *BigIntSpace,
10091009 target: Target,
10101010 sema_kit: ?Module.WipAnalysis,
1011 ) !BigIntConst {
1011 ) Module.CompileError!BigIntConst {
10121012 switch (val.tag()) {
10131013 .zero,
10141014 .bool_false,
......@@ -1035,6 +1035,14 @@ pub const Value = extern union {
10351035 return BigIntMutable.init(&space.limbs, x).toConst();
10361036 },
10371037
1038 .elem_ptr => {
1039 const elem_ptr = val.castTag(.elem_ptr).?.data;
1040 const array_addr = (try elem_ptr.array_ptr.getUnsignedIntAdvanced(target, sema_kit)).?;
1041 const elem_size = elem_ptr.elem_ty.abiSize(target);
1042 const new_addr = array_addr + elem_size * elem_ptr.index;
1043 return BigIntMutable.init(&space.limbs, new_addr).toConst();
1044 },
1045
10381046 else => unreachable,
10391047 }
10401048 }
......@@ -1815,7 +1823,10 @@ pub const Value = extern union {
18151823 return orderAgainstZeroAdvanced(lhs, null) catch unreachable;
18161824 }
18171825
1818 pub fn orderAgainstZeroAdvanced(lhs: Value, sema_kit: ?Module.WipAnalysis) !std.math.Order {
1826 pub fn orderAgainstZeroAdvanced(
1827 lhs: Value,
1828 sema_kit: ?Module.WipAnalysis,
1829 ) Module.CompileError!std.math.Order {
18191830 return switch (lhs.tag()) {
18201831 .zero,
18211832 .bool_false,
......@@ -1851,6 +1862,21 @@ pub const Value = extern union {
18511862 .float_80 => std.math.order(lhs.castTag(.float_80).?.data, 0),
18521863 .float_128 => std.math.order(lhs.castTag(.float_128).?.data, 0),
18531864
1865 .elem_ptr => {
1866 const elem_ptr = lhs.castTag(.elem_ptr).?.data;
1867 switch (try elem_ptr.array_ptr.orderAgainstZeroAdvanced(sema_kit)) {
1868 .lt => unreachable,
1869 .gt => return .gt,
1870 .eq => {
1871 if (elem_ptr.index == 0) {
1872 return .eq;
1873 } else {
1874 return .gt;
1875 }
1876 },
1877 }
1878 },
1879
18541880 else => unreachable,
18551881 };
18561882 }
test/behavior/pointers.zig+2-3
......@@ -366,11 +366,10 @@ test "pointer sentinel with +inf" {
366366}
367367
368368test "pointer to array at fixed address" {
369 if (builtin.zig_backend != .stage1) return error.SkipZigTest; // TODO
370
371 const array = @intToPtr(*volatile [1]u32, 0x10);
369 const array = @intToPtr(*volatile [2]u32, 0x10);
372370 // Silly check just to reference `array`
373371 try expect(@ptrToInt(&array[0]) == 0x10);
372 try expect(@ptrToInt(&array[1]) == 0x14);
374373}
375374
376375test "pointer arithmetic affects the alignment" {