[lld][ELF][test] Add additional --symbol-ordering-file testing

[jhenderson]

Summary

This covers a few cases that aren't otherwise tested:

1. Non-ascii symbol names are ordered.
2. Comments, whitespace and blank lines are trimmed.
3. Missing order files result in an error.

[MaskRay]

lld/test/ELF/symbol-ordering-file.s

35

46

Prepend error:

[jhenderson]

lld/test/ELF/symbol-ordering-file.s

35

Okay. I was deliberately trying to avoid testing the message in detail, since it somewhat duplicates coverage provided by symbol-ordering-file-warnings.s. Ideally, I'd not check it at all, but I want to show that there are no other warnings, caused by the whitespace/comments etc. However, I also don't want to lose the coverage given by the duplicate symbol (i.e. which one determines the order for that symbol). I'm open to alternative suggestions that would help with this.

[jhenderson]

Address review comments.

[grimar]

Have a minor question/suggestion. The rest LG.

lld/test/ELF/symbol-ordering-file.s

23

Does it make sence to test the mix of different line endings? I.e windows ("\r\n") vs linux ("\n")

[jhenderson]

Confirm all special whitespace characters are trimmed.

[jhenderson]

lld/test/ELF/symbol-ordering-file.s

23

I've gone further and tested all the special whitespace characters currently handled.

[grimar]

LGTM!

[MaskRay]

LGTM.

lld/test/ELF/symbol-ordering-file.s

 # REQUIRES: x86
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
 # RUN: ld.lld %t.o -o %t.out
 # RUN: llvm-objdump -s %t.out| FileCheck %s --check-prefix=BEFORE
 
 # BEFORE:      Contents of section .foo:
-# BEFORE-NEXT:  11223344 5566
+# BEFORE-NEXT:  11223344 556677
 # BEFORE:      Contents of section .init:
 # BEFORE-NEXT:  1122
 
 # RUN: echo "_foo4  " > %t_order.txt
 # RUN: echo "  _foo3" >> %t_order.txt
+# RUN: echo "_nönascii" >> %t_order.txt
 # RUN: echo "_foo5" >> %t_order.txt
-# RUN: echo "_foo2" >> %t_order.txt
+# RUN: echo -e " _foo2 \t\v\r\f" >> %t_order.txt
+# RUN: echo "# a comment" >> %t_order.txt
 # RUN: echo " " >> %t_order.txt
 # RUN: echo "_foo4" >> %t_order.txt
 # RUN: echo "_bar1" >> %t_order.txt
+# RUN: echo "" >> %t_order.txt
 # RUN: echo "_foo1" >> %t_order.txt
 # RUN: echo "_init2" >> %t_order.txt
 # RUN: echo "_init1" >> %t_order.txt
 
-# RUN: ld.lld --symbol-ordering-file %t_order.txt %t.o -o %t2.out
-# RUN: llvm-objdump -s %t2.out| FileCheck %s --check-prefix=AFTER
+## Show that both --symbol-ordering-file and --symbol-ordering-file= work.
+## Also show that lines beginning with '#', whitespace and empty lines, are ignored.
+## Also show that "first one wins" when there are duplicate symbols in the order
+## file (a warning will be emitted).
+# RUN: ld.lld --symbol-ordering-file %t_order.txt %t.o -o %t2.out 2>&1 | \
+# RUN:   FileCheck %s --check-prefix=WARN --implicit-check-not=warning:
+# RUN: llvm-objdump -s %t2.out | FileCheck %s --check-prefix=AFTER
 # RUN: ld.lld --symbol-ordering-file=%t_order.txt %t.o -o %t2.out
-# RUN: llvm-objdump -s %t2.out| FileCheck %s --check-prefix=AFTER
+# RUN: llvm-objdump -s %t2.out | FileCheck %s --check-prefix=AFTER
 
+# WARN: warning: {{.*}}.txt: duplicate ordered symbol
+
 # AFTER:      Contents of section .foo:
-# AFTER-NEXT:  44335566 2211
+# AFTER-NEXT:  44337755 662211
 # AFTER:      Contents of section .init:
 # AFTER-NEXT:  1122
 
+## Show that a nonexistent symbol ordering file causes an error.
+# RUN: not ld.lld --symbol-ordering-file=%t.nonexistent %t.o -o %t3.out 2>&1 | \
+# RUN:   FileCheck %s --check-prefix=ERR -DFILE=%t.nonexistent
+
+# ERR: error: cannot open [[FILE]]: {{[Nn]}}o such file or directory
+
+## Show that an empty ordering file can be handled (symbols remain in their
+## normal order).
+# RUN: touch %t.empty
+# RUN: ld.lld --symbol-ordering-file=%t.empty %t.o -o %t4.out
+# RUN: llvm-objdump -s %t4.out | FileCheck %s --check-prefix=BEFORE
+
 .section .foo,"ax",@progbits,unique,1
 _foo1:
  .byte 0x11
 
 .section .foo,"ax",@progbits,unique,2
 _foo2:
  .byte 0x22
 
 .section .foo,"ax",@progbits,unique,3
 _foo3:
  .byte 0x33
 
 .section .foo,"ax",@progbits,unique,4
 _foo4:
  .byte 0x44
 
 .section .foo,"ax",@progbits,unique,5
 _foo5:
  .byte 0x55
 _bar1:
  .byte 0x66
 
+.section .foo,"ax",@progbits,unique,6
+"_nönascii":
+.byte 0x77
+
 .section .init,"ax",@progbits,unique,1
 _init1:
  .byte 0x11
 
 .section .init,"ax",@progbits,unique,2
 _init2:
  .byte 0x22
+
+.text
+.global _start
+_start:
+    nop