[llvm-readelf] - Report unique warnings when dumping hash symbols/histogram.

[grimar]

Summary

This converts 2 more places to use reportUniqueWarning and adds tests.

[jhenderson]

LGTM.

llvm/test/tools/llvm-readobj/ELF/hash-histogram.test

ProgramHeaders:
   - Type:     PT_LOAD
     FirstSec: .hash
     LastSec:  .dynamic
 
 ## Show that we report a warning for a hash table which contains an entry of
 ## the bucket array pointing to a cycle.
 
 # RUN: yaml2obj --docnum=2 %s -o %t2.o
-# RUN: llvm-readelf --elf-hash-histogram 2>&1 %t2.o | FileCheck -DFILE=%t2.o %s --check-prefix=BROKEN
+# RUN: llvm-readelf --elf-hash-histogram 2>&1 %t2.o | \
+# RUN:   FileCheck -DFILE=%t2.o %s --check-prefix=BROKEN --implicit-check-not=warning:
 
 # BROKEN:       warning: '[[FILE]]': .hash section is invalid: bucket 1: a cycle was detected in the linked chain
-# BROKEN:       Histogram for bucket list length (total of 1 buckets)
+# BROKEN:       Histogram for bucket list length (total of 2 buckets)
 # BROKEN-NEXT:  Length  Number     % of total  Coverage
 # BROKEN-NEXT:       0  0          (  0.0%)       0.0%
-# BROKEN-NEXT:       1  1          (100.0%)     100.0%
+# BROKEN-NEXT:       1  2          (100.0%)     100.0%
 
 --- !ELF
 FileHeader:
   Class: ELFCLASS32
   Data:  ELFDATA2LSB
   Type:  ET_REL
 Sections:
   - Name:   .hash
     Type:   SHT_HASH
     Link:   .dynsym
-    Bucket: [ 1 ]
+    Bucket: [ 1, 1 ]
     Chain:  [ 0, 1 ]
   - Name:  .dynamic
     Type:  SHT_DYNAMIC
     Flags: [ SHF_ALLOC ]
     Entries:
 ## llvm-readelf will read the hash table from the file offset
 ## p_offset + (p_vaddr - DT_HASH) = p_offset + (0 - 0) = p_offset,
 ## which is the start of PT_LOAD, i.e. the file offset of .hash.

llvm/test/tools/llvm-readobj/ELF/hash-symbols.test

- Type:     PT_DYNAMIC
     VAddr:    0x1000
     FirstSec: .dynamic
     LastSec:  .dynamic
 
 ## Show that we report a warning for a hash table which contains an entry of
 ## the bucket array pointing to a cycle.
 
 # RUN: yaml2obj --docnum=5 %s -o %t5.so
-# RUN: llvm-readelf --hash-symbols %t5.so 2>&1 | FileCheck %s -DFILE=%t5.so --check-prefix=BROKEN
+# RUN: llvm-readelf --hash-symbols %t5.so 2>&1 | \
+# RUN:   FileCheck %s -DFILE=%t5.so --check-prefix=BROKEN --implicit-check-not=warning:
 
 # BROKEN:      Symbol table of .hash for image:
 # BROKEN-NEXT:  Num Buc:    Value  Size   Type   Bind Vis      Ndx Name
 # BROKEN-NEXT:    1   0: 00000000     0 NOTYPE  LOCAL  DEFAULT UND aaa
 # BROKEN: warning: '[[FILE]]': .hash section is invalid: bucket 1: a cycle was detected in the linked chain
+# BROKEN-NEXT:    1   1: 00000000     0 NOTYPE  LOCAL  DEFAULT UND aaa
+# BROKEN-NOT: {{.}}
 
 --- !ELF
 FileHeader:
   Class: ELFCLASS32
   Data:  ELFDATA2LSB
   Type:  ET_DYN
 Sections:
   - Name:    .hash
     Type:    SHT_HASH
     Link:    .dynsym
-    Bucket:  [ 1 ]
+    Bucket:  [ 1, 1 ]
     Chain:   [ 1, 1 ]
   - Name:  .dynamic
     Type:  SHT_DYNAMIC
     Entries:
 ## llvm-readelf will read the hash table from the file offset
 ## p_offset + (p_vaddr - DT_HASH) = p_offset + (0 - 0) = p_offset,
 ## which is the start of PT_LOAD, i.e. the file offset of .hash.
       - Tag:   DT_HASH
         Value: 0x0
 DynamicSymbols:
-  - Name:    aaa
-  - Name:    bbb
+  - Name: aaa
 ProgramHeaders:
   - Type:     PT_LOAD
     FirstSec: .hash
     LastSec:  .dynamic
 
 ## Each SHT_HASH section starts with two 32-bit fields: nbucket and nchain.
 ## Check we report an error when a DT_HASH value points to data that has size less than 8 bytes.
 

llvm/tools/llvm-readobj/ELFDumper.cpp

for (uint32_t Buc = 0; Buc < SysVHash.nbucket; Buc++) {
     if (Buckets[Buc] == ELF::STN_UNDEF)
       continue;
     std::vector<bool> Visited(SysVHash.nchain);
     for (uint32_t Ch = Buckets[Buc]; Ch < SysVHash.nchain; Ch = Chains[Ch]) {
       if (Ch == ELF::STN_UNDEF)
         break;
 
       if (Visited[Ch]) {
-        reportWarning(createError(".hash section is invalid: bucket " +
+        this->reportUniqueWarning(".hash section is invalid: bucket " +
                                   Twine(Ch) +
-                                  ": a cycle was detected in the linked chain"),
-                      this->FileName);
+                                  ": a cycle was detected in the linked chain");
         break;
       }
 
       printHashedSymbol(FirstSym + Ch, Ch, StringTable, Buc);
       Visited[Ch] = true;
     }
   }
 }
void GNUStyle<ELFT>::printHashHistogram(const Elf_Hash &HashTable) {
   // Go over all buckets and and note chain lengths of each bucket (total
   // unique chain lengths).
   for (size_t B = 0; B < NBucket; B++) {
     std::vector<bool> Visited(NChain);
     for (size_t C = Buckets[B]; C < NChain; C = Chains[C]) {
       if (C == ELF::STN_UNDEF)
         break;
       if (Visited[C]) {
-        reportWarning(createError(".hash section is invalid: bucket " +
+        this->reportUniqueWarning(".hash section is invalid: bucket " +
                                   Twine(C) +
-                                  ": a cycle was detected in the linked chain"),
-                      this->FileName);
+                                  ": a cycle was detected in the linked chain");
         break;
       }
       Visited[C] = true;
       if (MaxChain <= ++ChainLen[B])
         MaxChain++;
     }
     TotalSyms += ChainLen[B];
   }