[PATCH] D20466: [MC/ELF] - Fixed incorrect compression.s test

[Rafael Espíndola via llvm-commits]

This does two things:

* Change dwarfdump to print a section that is actually compressed, that is good.
* Change the CHECK patters to check the full content of the sections.
I am not sure why you are doing that.

Cheers,
Rafael


On 20 May 2016 at 06:14, George Rimar <grimar at accesssoftek.com> wrote:
> grimar created this revision.
> grimar added reviewers: rafael, davide, dblaikie.
> grimar added subscribers: llvm-commits, grimar.
>
> This test looks to be incorrect.
> Main problem that .debug_info
> section was used to check that llvm-dwarfdump is able to decompress
> data that was compressed with llvm-mc tool.
>
> That was probably not noticable, so I slightly refactored whole one,
> so test checkcases shows the internals in more obvious way now.
>
> I changed testcase to use .debug_str section which is one that
> is really compressed. So currently test do what is probably was expected to do:
> checks that "data"->llvm-mc->llvm-dwarfdump->dumps back initial "data".
>
>
> http://reviews.llvm.org/D20466
>
> Files:
>   compression.s
>
> Index: compression.s
> ===================================================================
> --- compression.s
> +++ compression.s
> @@ -1,30 +1,37 @@
>  // RUN: llvm-mc -filetype=obj -compress-debug-sections -triple x86_64-pc-linux-gnu < %s -o %t
>  // RUN: llvm-objdump -s %t | FileCheck %s
> -// RUN: llvm-dwarfdump -debug-dump=info %t | FileCheck --check-prefix=INFO %s
> +// RUN: llvm-dwarfdump -debug-dump=str %t | FileCheck --check-prefix=STR %s
>  // RUN: llvm-mc -filetype=obj -compress-debug-sections -triple i386-pc-linux-gnu < %s \
>  // RUN:     | llvm-readobj -symbols - | FileCheck --check-prefix=386-SYMBOLS %s
>
>  // REQUIRES: zlib
>
> -// CHECK: Contents of section .zdebug_line:
> -// Check for the 'ZLIB' file magic at the start of the section only
> -// CHECK-NEXT: ZLIB
> -// CHECK-NOT: ZLIB
> -
> -// Don't compress small sections, such as this simple debug_abbrev example
> -// CHECK: Contents of section .debug_abbrev:
> -// CHECK-NOT: ZLIB
> -// CHECK-NOT: Contents of
> -
> -// CHECK: Contents of section .debug_info:
> -
> +// Check what happens with debug sections. Small ones are not compressed, so
> +// using of compression should not make result larger
>  // FIXME: Handle compressing alignment fragments to support compressing debug_frame
> -// CHECK: Contents of section .debug_frame:
> -// CHECK-NOT: ZLIB
> -// CHECK: Contents of
> -
> -// Decompress one valid dwarf section just to check that this roundtrips
> -// INFO: 0x00000000: Compile Unit: length = 0x0000000c version = 0x0004 abbr_offset = 0x0000 addr_size = 0x08 (next unit at 0x00000010)
> +//
> +// CHECK:      Contents of section .zdebug_line:
> +// CHECK-NEXT:  0000 5a4c4942 00000000 00000041 789cb365  ZLIB.......Ax..e
> +// CHECK-NEXT:  0010 60606062 5000928c 8cbff978 81242323  ```bP......x.$##
> +// CHECK-NEXT:  0020 8803422e 459965a9 457a9999 0c60c0c9  ..B.E.e.Ez...`..
> +// CHECK-NEXT:  0030 c40005c2 8a60c0c4 08540e00 cbdf05d3  .....`...T......
> +// CHECK:      Contents of section .debug_abbrev:
> +// CHECK-NEXT:  0000 0111001b 0e0000                      .......
> +// CHECK:      Contents of section .debug_info:
> +// CHECK-NEXT:  0000 0c000000 04000000 00000801 00000000  ................
> +// CHECK:      Contents of section .zdebug_str:
> +// CHECK-NEXT:  0000 5a4c4942 00000000 0000004d 789c2b48  ZLIB.......Mx.+H
> +// CHECK-NEXT:  0010 2d4a4b4d 2ec9a954 48cecf2d 284a2d2e  -JKM...TH..-(J-.
> +// CHECK-NEXT:  0020 4e4cca49 5548492c 4954284e cc2d00b2  NL.IUHI,IT(N.-..
> +// CHECK-NEXT:  0030 b588050c 00c17e14 25                 ......~.%
> +// CHECK:      Contents of section .debug_frame:
> +// CHECK-NEXT:  0000 14000000 ffffffff 04000800 0178100c  .............x..
> +// CHECK-NEXT:  0010 07089001 00000000 14000000 00000000  ................
> +// CHECK-NEXT:  0020 00000000 00000000 07000000 00000000  ................
> +
> +// Decompress one valid dwarf section just to check that this roundtrips,
> +// we use .zdebug_str section for that
> +// STR: perfectly compressable data sample *****************************************
>
>  // In x86 32 bit named symbols are used for temporary symbols in merge
>  // sections, so make sure we handle symbols inside compressed sections
> @@ -74,6 +81,9 @@
>         .cfi_endproc
>         .cfi_sections .debug_frame
>
> +# Below is the section we will use to check that after compression with llvm-mc,
> +# llvm-dwarfdump tool will be able to decompress data back and dump it. Data sample
> +# should be compressable enough, so it is filled with some amount of equal symbols at the end
>         .section        .debug_str,"MS", at progbits,1
>  .Linfo_string0:
> -        .asciz  "compress this                                    "
> +        .asciz  "perfectly compressable data sample *****************************************"
>
>