| ... | ... | @@ -1685,6 +1685,7 @@ fn airLoad(self: *Self, inst: Air.Inst.Index) !void { |
| 1685 | 1685 | |
| 1686 | 1686 | fn store(self: *Self, ptr: MCValue, value: MCValue, ptr_ty: Type, value_ty: Type) InnerError!void { |
| 1687 | 1687 | _ = ptr_ty; |
| 1688 | const abi_size = value_ty.abiSize(self.target.*); |
| 1688 | 1689 | switch (ptr) { |
| 1689 | 1690 | .none => unreachable, |
| 1690 | 1691 | .undef => unreachable, |
| ... | ... | @@ -1705,6 +1706,9 @@ fn store(self: *Self, ptr: MCValue, value: MCValue, ptr_ty: Type, value_ty: Type |
| 1705 | 1706 | return self.fail("TODO implement storing to MCValue.embedded_in_code", .{}); |
| 1706 | 1707 | }, |
| 1707 | 1708 | .register => |reg| { |
| 1709 | self.register_manager.freezeRegs(&.{reg}); |
| 1710 | defer self.register_manager.unfreezeRegs(&.{reg}); |
| 1711 | |
| 1708 | 1712 | switch (value) { |
| 1709 | 1713 | .none => unreachable, |
| 1710 | 1714 | .undef => unreachable, |
| ... | ... | @@ -1713,7 +1717,6 @@ fn store(self: *Self, ptr: MCValue, value: MCValue, ptr_ty: Type, value_ty: Type |
| 1713 | 1717 | .compare_flags_unsigned => unreachable, |
| 1714 | 1718 | .compare_flags_signed => unreachable, |
| 1715 | 1719 | .immediate => |imm| { |
| 1716 | | const abi_size = value_ty.abiSize(self.target.*); |
| 1717 | 1720 | switch (abi_size) { |
| 1718 | 1721 | 1, 2, 4 => { |
| 1719 | 1722 | // TODO this is wasteful! |
| ... | ... | @@ -1760,7 +1763,6 @@ fn store(self: *Self, ptr: MCValue, value: MCValue, ptr_ty: Type, value_ty: Type |
| 1760 | 1763 | } |
| 1761 | 1764 | }, |
| 1762 | 1765 | .register => |src_reg| { |
| 1763 | | const abi_size = value_ty.abiSize(self.target.*); |
| 1764 | 1766 | _ = try self.addInst(.{ |
| 1765 | 1767 | .tag = .mov, |
| 1766 | 1768 | .ops = (Mir.Ops{ |
| ... | ... | @@ -1777,9 +1779,16 @@ fn store(self: *Self, ptr: MCValue, value: MCValue, ptr_ty: Type, value_ty: Type |
| 1777 | 1779 | } |
| 1778 | 1780 | }, |
| 1779 | 1781 | .memory => |addr| { |
| 1782 | if (self.bin_file.options.pie) { |
| 1783 | return self.fail("TODO implement storing to memory when targeting PIE", .{}); |
| 1784 | } |
| 1785 | |
| 1780 | 1786 | // TODO: in case the address fits in an imm32 we can use [ds:imm32] |
| 1781 | 1787 | // instead of wasting an instruction copying the address to a register |
| 1782 | 1788 | |
| 1789 | if (value.isRegister()) self.register_manager.freezeRegs(&.{value.register}); |
| 1790 | defer if (value.isRegister()) self.register_manager.unfreezeRegs(&.{value.register}); |
| 1791 | |
| 1783 | 1792 | const addr_reg = try self.copyToTmpRegister(ptr_ty, .{ .immediate = addr }); |
| 1784 | 1793 | // to get the actual address of the value we want to modify we have to go through the GOT |
| 1785 | 1794 | // mov reg, [reg] |
| ... | ... | @@ -1793,37 +1802,39 @@ fn store(self: *Self, ptr: MCValue, value: MCValue, ptr_ty: Type, value_ty: Type |
| 1793 | 1802 | .data = .{ .imm = 0 }, |
| 1794 | 1803 | }); |
| 1795 | 1804 | |
| 1796 | | const abi_size = value_ty.abiSize(self.target.*); |
| 1797 | 1805 | switch (value) { |
| 1798 | 1806 | .immediate => |imm| { |
| 1807 | if (abi_size > 8) { |
| 1808 | return self.fail("TODO saving imm to memory for abi_size {}", .{abi_size}); |
| 1809 | } |
| 1810 | |
| 1799 | 1811 | const payload = try self.addExtra(Mir.ImmPair{ |
| 1800 | 1812 | .dest_off = 0, |
| 1801 | 1813 | .operand = @intCast(u32, imm), |
| 1802 | 1814 | }); |
| 1815 | const flags: u2 = switch (abi_size) { |
| 1816 | 1 => 0b00, |
| 1817 | 2 => 0b01, |
| 1818 | 4 => 0b10, |
| 1819 | 8 => 0b11, |
| 1820 | else => unreachable, |
| 1821 | }; |
| 1822 | if (flags == 0b11) { |
| 1823 | const top_bits: u32 = @intCast(u32, imm >> 32); |
| 1824 | const can_extend = if (value_ty.isUnsignedInt()) |
| 1825 | (top_bits == 0) and (imm & 0x8000_0000) == 0 |
| 1826 | else |
| 1827 | top_bits == 0xffff_ffff; |
| 1828 | |
| 1829 | if (!can_extend) { |
| 1830 | return self.fail("TODO imm64 would get incorrectly sign extended", .{}); |
| 1831 | } |
| 1832 | } |
| 1803 | 1833 | _ = try self.addInst(.{ |
| 1804 | 1834 | .tag = .mov_mem_imm, |
| 1805 | 1835 | .ops = (Mir.Ops{ |
| 1806 | 1836 | .reg1 = addr_reg.to64(), |
| 1807 | | .flags = switch (abi_size) { |
| 1808 | | 1 => 0b00, |
| 1809 | | 2 => 0b01, |
| 1810 | | 4 => 0b10, |
| 1811 | | 8 => flag: { |
| 1812 | | const top_bits: u32 = @intCast(u32, imm >> 32); |
| 1813 | | const can_extend = if (value_ty.isUnsignedInt()) |
| 1814 | | (top_bits == 0) and (imm & 0x8000_0000) == 0 |
| 1815 | | else |
| 1816 | | top_bits == 0xffff_ffff; |
| 1817 | | |
| 1818 | | if (!can_extend) { |
| 1819 | | return self.fail("TODO imm64 would get incorrectly sign extended", .{}); |
| 1820 | | } |
| 1821 | | break :flag 0b11; |
| 1822 | | }, |
| 1823 | | else => { |
| 1824 | | return self.fail("TODO saving imm to memory for abi_size {}", .{abi_size}); |
| 1825 | | }, |
| 1826 | | }, |
| 1837 | .flags = flags, |
| 1827 | 1838 | }).encode(), |
| 1828 | 1839 | .data = .{ .payload = payload }, |
| 1829 | 1840 | }); |
Jakub Konka <kubkon@jakubkonka.com> 2022-02-03 14:31:16+01:00
src