[ELF] -M/-Map: fix VMA/LMA/Size columns of symbol assignments when address/size>=2**32

[MaskRay]

Summary

SymbolAssignment::addr stores the location counter. The type should be
uint64_t instead of unsigned. The upper half of the address space is
commonly used by operating system kernels.

Similarly, SymbolAssignment::size should be an uint64_t. A kernel linker
script can move the location counter from 0 to the upper half of the
address space.

[grimar]

The code change LG, few comments about the test.

lld/test/ELF/map-file-kernel.s

1

map-file-kernel.s probably doesn't describe the intention of the test? Not sure why there is "kernel" mentioned.

7

The second check line looks broken/shifted because of the huge size it seems, isn't?
Are we going to fix it or was your intention just to document this behavior?
(If we want to fix this, I guess it can be done in another patch, but I'd probably add a comment regarding this line then).

11

Perhaps would be good to add the comment daying what we wanted to test here.
Without knowledge about the code change it is unclear what is tested perhaps.

[MaskRay]

Address comments

[MaskRay]

lld/test/ELF/map-file-kernel.s

1

Renamed to map-file-64bit.s

7

Just to document the behavior. This is very uncommon. In an arbitrary Linux vmlinux.lds, there is only one such line: there is just one far-distance symbol assignment.

[grimar]

LGTM

lld/ELF/LinkerScript.h

 //===- LinkerScript.h -------------------------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
struct SymbolAssignment : BaseCommand {
 
   // Holds file name and line number for error reporting.
   std::string location;
 
   // A string representation of this command. We use this for -Map.
   std::string commandString;
 
   // Address of this assignment command.
-  unsigned addr;
+  uint64_t addr;
 
   // Size of this assignment command. This is usually 0, but if
   // you move '.' this may be greater than 0.
-  unsigned size;
+  uint64_t size;
 };
 
 // Linker scripts allow additional constraints to be put on output sections.
 // If an output section is marked as ONLY_IF_RO, the section is created
 // only if its input sections are read-only. Likewise, an output section
 // with ONLY_IF_RW is created if all input sections are RW.
 enum class ConstraintKind { NoConstraint, ReadOnly, ReadWrite };
 

lld/test/ELF/map-file-kernel.s

+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64 /dev/null -o %t.o
+# RUN: ld.lld -M -T %s %t.o -o /dev/null | FileCheck %s --match-full-lines --strict-whitespace
+
+#      CHECK:             VMA              LMA     Size Align Out     In      Symbol
+# CHECK-NEXT:               0                0 ffffffff80000000     1 . = 0xffffffff80000000
+# CHECK-NEXT:ffffffff80000000                0   100000     1 . += 0x100000
+# CHECK-NEXT:ffffffff80100000                0        0     1 _text = .
+# CHECK-NEXT:ffffffff80100000 ffffffff80100000        0     4 .text
+
+SECTIONS {
+  . = 0xffffffff80000000;
+  . += 0x100000;
+  _text = .;
+}