[llvm-objcopy] - Calculate the string table section sizes correctly.

This fixes the https://bugs.llvm.org/show_bug.cgi?id=40980.

Previously if string optimization occurred as a result of
StringTableBuilder's finalize() method, the size wasn't updated.

This hopefully also makes the interaction between sections during finalization
processes a bit more clear.

Differential revision: https://reviews.llvm.org/D59488

llvm-svn: 356371

1 files changed, 28 insertions, 0 deletions

diff --git a/llvm/test/tools/llvm-objcopy/ELF/shstrtab-optimize.test b/llvm/test/tools/llvm-objcopy/ELF/shstrtab-optimize.test
new file mode 100644
index 00000000000..24b546cbaf5
--- /dev/null
+++ b/llvm/test/tools/llvm-objcopy/ELF/shstrtab-optimize.test
@@ -0,0 +1,28 @@
+# RUN: yaml2obj %s > %t
+# RUN: llvm-objcopy %t %t2
+# RUN: llvm-readobj --sections %t2 | FileCheck %s
+
+## Check we have the correct size of the .shstrtab section
+## after the strings tail merge optimization.
+
+# CHECK:      Name: .shstrtab
+# CHECK-NEXT: Type: SHT_STRTAB
+# CHECK-NEXT: Flags [
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address:
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size: 36
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .bar
+    Type:            SHT_PROGBITS
+    Flags:           [ ]
+  - Name:            .foo.bar
+    Type:            SHT_PROGBITS
+    Flags:           [ ]