[llvm-readelf] Print a blank line for the first hex/string dump

GNU readelf prints a blank line before the first hex/string dump, which
serves as a separator when there are other dump operations. Port the
behavior.

Pull Request: https://github.com/llvm/llvm-project/pull/85744

8 files changed, 24 insertions, 21 deletions

diff --git a/llvm/test/tools/llvm-readobj/ELF/decompress-zlib-unsupported.test b/llvm/test/tools/llvm-readobj/ELF/decompress-zlib-unsupported.test
index f4c73de..083c296 100644
--- a/llvm/test/tools/llvm-readobj/ELF/decompress-zlib-unsupported.test
+++ b/llvm/test/tools/llvm-readobj/ELF/decompress-zlib-unsupported.test
@@ -10,6 +10,7 @@
 # CHECK-NEXT: [    18] x.c.
 # CHECK-NEXT: [    1e] .
 # CHECK-NEXT: [    20] .
+# CHECK-EMPTY:
 # CHECK-NEXT: Hex dump of section '.b':
 # CHECK-NEXT: warning: '[[FILE]]': LLVM was not built with LLVM_ENABLE_ZLIB or did not find zlib at build time
 # CHECK-NEXT: 0x00000000 01000000 00000000 01000000 00000000 ................
diff --git a/llvm/test/tools/llvm-readobj/ELF/decompress-zlib.test b/llvm/test/tools/llvm-readobj/ELF/decompress-zlib.test
index ea7a885..c1d12a6 100644
--- a/llvm/test/tools/llvm-readobj/ELF/decompress-zlib.test
+++ b/llvm/test/tools/llvm-readobj/ELF/decompress-zlib.test
@@ -28,6 +28,7 @@
 # COMPRESSED:      String dump of section '.not_null_terminated':
 # COMPRESSED-NEXT: [     0] no
 # COMPRESSED-NEXT: [     3] null
+# COMPRESSED-EMPTY:
 # COMPRESSED-NEXT: Hex dump of section '.strings':
 # COMPRESSED-NEXT: 0x00000000 01000000 00000000 16000000 00000000 ................
 # COMPRESSED-NEXT: 0x00000010 00000000 00000000 789ccb48 2d4a6548 ........x..H-JeH
@@ -39,6 +40,7 @@
 # INVALID:      String dump of section '.invalid1':
 # INVALID-NEXT: warning: '[[FILE]]': corrupted compressed section header
 # INVALID-NEXT: [     0] .
+# INVALID-EMPTY:
 # INVALID-NEXT: Hex dump of section '.invalid2':
 # INVALID-NEXT: warning: '[[FILE]]': zlib error: Z_DATA_ERROR
 # INVALID-NEXT: 0x00000000 01000000 00000000 16000000 00000000 ................
diff --git a/llvm/test/tools/llvm-readobj/ELF/decompress-zstd-unsupported.test b/llvm/test/tools/llvm-readobj/ELF/decompress-zstd-unsupported.test
index 65da952..98c7cb0 100644
--- a/llvm/test/tools/llvm-readobj/ELF/decompress-zstd-unsupported.test
+++ b/llvm/test/tools/llvm-readobj/ELF/decompress-zstd-unsupported.test
@@ -9,6 +9,7 @@
 # CHECK-NEXT: [    10] .
 # CHECK-NEXT: [    18] (./. ..
 # CHECK-NEXT: [    21] .
+# CHECK-EMPTY:
 # CHECK-NEXT: Hex dump of section '.b':
 # CHECK-NEXT: warning: '[[FILE]]': LLVM was not built with LLVM_ENABLE_ZSTD or did not find zstd at build time
 # CHECK-NEXT: 0x00000000 02000000 00000000 01000000 00000000 ................
diff --git a/llvm/test/tools/llvm-readobj/ELF/hex-dump-multi.s b/llvm/test/tools/llvm-readobj/ELF/hex-dump-multi.s
index 33ef534..942bfc4 100644
--- a/llvm/test/tools/llvm-readobj/ELF/hex-dump-multi.s
+++ b/llvm/test/tools/llvm-readobj/ELF/hex-dump-multi.s
@@ -1,10 +1,12 @@
 # REQUIRES: x86-registered-target
 
 # RUN: llvm-mc -filetype=obj -triple x86_64 %s -o %t.o
-# RUN: llvm-readobj -x .a -x .b %t.o | FileCheck %s
+# RUN: llvm-readobj -x .a -x .b %t.o | FileCheck %s --check-prefixes=HEADER,CHECK
 # RUN: llvm-readelf -x .a -x .b %t.o | FileCheck %s
 
-# CHECK:      Hex dump of section '.a':
+# HEADER:     LoadName:
+# CHECK:      {{^$}}
+# CHECK-NEXT: Hex dump of section '.a':
 # CHECK-NEXT: 0x00000000 00
 # CHECK-EMPTY:
 # CHECK-NEXT: Hex dump of section '.b':
diff --git a/llvm/test/tools/llvm-readobj/ELF/hex-dump.test b/llvm/test/tools/llvm-readobj/ELF/hex-dump.test
index 7829944..71212de 100644
--- a/llvm/test/tools/llvm-readobj/ELF/hex-dump.test
+++ b/llvm/test/tools/llvm-readobj/ELF/hex-dump.test
@@ -46,7 +46,8 @@ FileHeader:
 # RUN: llvm-readelf --hex-dump=.sec %t2.out1 | \
 # RUN:   FileCheck %s --match-full-lines --strict-whitespace --check-prefix=SPACES1
 
-#      SPACES1:Hex dump of section '.sec':
+#      SPACES1:{{^$}}
+# SPACES1-NEXT:Hex dump of section '.sec':
 # SPACES1-NEXT:0x00000000 00000000 00000000 00000000 00000000 ................
 # SPACES1-NEXT:0x00000010 0000                                ..
 
@@ -55,7 +56,8 @@ FileHeader:
 # RUN: llvm-readelf --hex-dump=.sec %t2.out2 | \
 # RUN:   FileCheck %s --match-full-lines --strict-whitespace --check-prefix=SPACES2
 
-#      SPACES2:Hex dump of section '.sec':
+#      SPACES2:{{^$}}
+# SPACES2-NEXT:Hex dump of section '.sec':
 # SPACES2-NEXT:0x00000000 00000000 00000000 00000000 00000000 ................
 # SPACES2-NEXT:0x00000010 00000000 00000000 00000000 0000     ..............
 
@@ -64,7 +66,8 @@ FileHeader:
 # RUN: llvm-readelf --hex-dump=.sec %t2.out3 | \
 # RUN:   FileCheck %s --match-full-lines --strict-whitespace --check-prefix=SPACES3
 
-#      SPACES3:Hex dump of section '.sec':
+#      SPACES3:{{^$}}
+# SPACES3-NEXT:Hex dump of section '.sec':
 # SPACES3-NEXT:0x00000000 00000000 00000000 00000000 00000000 ................
 # SPACES3-NEXT:0x00000010 00000000 00000000 00000000          ............
 
diff --git a/llvm/test/tools/llvm-readobj/ELF/string-dump-multi.s b/llvm/test/tools/llvm-readobj/ELF/string-dump-multi.s
index 29d7ef0..36a115b 100644
--- a/llvm/test/tools/llvm-readobj/ELF/string-dump-multi.s
+++ b/llvm/test/tools/llvm-readobj/ELF/string-dump-multi.s
@@ -1,10 +1,12 @@
 # REQUIRES: x86-registered-target
 
 # RUN: llvm-mc -filetype=obj -triple x86_64 %s -o %t.o
-# RUN: llvm-readobj -p .a -p .b %t.o | FileCheck %s
+# RUN: llvm-readobj -p .a -p .b %t.o | FileCheck %s --check-prefixes=HEADER,CHECK
 # RUN: llvm-readelf -p .a -p .b %t.o | FileCheck %s
 
-# CHECK:      String dump of section '.a':
+# HEADER:     LoadName:
+# CHECK:      {{^$}}
+# CHECK-NEXT: String dump of section '.a':
 # CHECK-NEXT: [     0] 0
 # CHECK-EMPTY:
 # CHECK-NEXT: String dump of section '.b':
diff --git a/llvm/test/tools/llvm-readobj/ELF/string-dump.test b/llvm/test/tools/llvm-readobj/ELF/string-dump.test
index c06b274..1d7a177b 100644
--- a/llvm/test/tools/llvm-readobj/ELF/string-dump.test
+++ b/llvm/test/tools/llvm-readobj/ELF/string-dump.test
@@ -3,7 +3,7 @@
 
 # RUN: llvm-readobj --string-dump=.strings \
 # RUN:   --string-dump=.not_null_terminated %t > %t.readobj.out
-# RUN: FileCheck %s --input-file=%t.readobj.out
+# RUN: FileCheck %s --input-file=%t.readobj.out --check-prefixes=HEADER,CHECK
 
 # Also test the different ways --string-dump can be specified, i.e. as a short
 # flag (-p), with different prefix modes (-p .foo, -p=.foo, -p.foo), and with
@@ -23,7 +23,9 @@
 # RUN: llvm-readelf -hp1 -p2 %t | cmp %t.readelf.out -
 # RUN: llvm-readelf -hp 1 -p.not_null_terminated %t | cmp %t.readelf.out -
 
-# CHECK:      String dump of section '.strings':
+# HEADER:     LoadName:
+# CHECK:      {{^$}}
+# CHECK-NEXT: String dump of section '.strings':
 # CHECK-NEXT: [ 0] here
 # CHECK-NEXT: [ 5] are
 # CHECK-NEXT: [ 9] some
diff --git a/llvm/tools/llvm-readobj/ObjDumper.cpp b/llvm/tools/llvm-readobj/ObjDumper.cpp
index 0d3fea7..0980d2a 100644
--- a/llvm/tools/llvm-readobj/ObjDumper.cpp
+++ b/llvm/tools/llvm-readobj/ObjDumper.cpp
@@ -160,15 +160,10 @@ void ObjDumper::printSectionsAsString(const object::ObjectFile &Obj,
                                       ArrayRef<std::string> Sections,
                                       bool Decompress) {
   SmallString<0> Out;
-  bool First = true;
   for (object::SectionRef Section :
        getSectionRefsByNameOrIndex(Obj, Sections)) {
     StringRef SectionName = unwrapOrError(Obj.getFileName(), Section.getName());
-
-    if (!First)
-      W.startLine() << '\n';
-    First = false;
-    W.startLine() << "String dump of section '" << SectionName << "':\n";
+    W.startLine() << "\nString dump of section '" << SectionName << "':\n";
 
     StringRef SectionContent =
         unwrapOrError(Obj.getFileName(), Section.getContents());
@@ -182,15 +177,10 @@ void ObjDumper::printSectionsAsHex(const object::ObjectFile &Obj,
                                    ArrayRef<std::string> Sections,
                                    bool Decompress) {
   SmallString<0> Out;
-  bool First = true;
   for (object::SectionRef Section :
        getSectionRefsByNameOrIndex(Obj, Sections)) {
     StringRef SectionName = unwrapOrError(Obj.getFileName(), Section.getName());
-
-    if (!First)
-      W.startLine() << '\n';
-    First = false;
-    W.startLine() << "Hex dump of section '" << SectionName << "':\n";
+    W.startLine() << "\nHex dump of section '" << SectionName << "':\n";
 
     StringRef SectionContent =
         unwrapOrError(Obj.getFileName(), Section.getContents());