[llvm-objcopy] Add support for removing sections
This change adds support for removing sections using the -R field (as
GNU objcopy does as well). This change should let us add many helpful
tests and is a proper stepping stone for adding more general kinds of
stripping.
Differential Revision: https://reviews.llvm.org/D38260
llvm-svn: 315346
diff --git a/llvm/test/tools/llvm-objcopy/segment-test-remove-section.test b/llvm/test/tools/llvm-objcopy/segment-test-remove-section.test
new file mode 100644
index 0000000..9b98dc8
--- /dev/null
+++ b/llvm/test/tools/llvm-objcopy/segment-test-remove-section.test
@@ -0,0 +1,156 @@
+# This test is checking to ensure that if a section is removed in the presence
+# of a segment that the segment maintains its shape and properties and that any
+# section inside that segment maintains the relative positioning it had in the
+# segment. Note worthy is that .text3 keeps its offset despite it being
+# possible to place it after .text when .text2 is removed.
+
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy -R .text2 %t %t2
+# RUN: llvm-readobj -file-headers -program-headers -sections %t2 | FileCheck %s
+# RUN: od -t x1 -j 8192 %t2 | FileCheck %s --check-prefix=DATA
+
+!ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_EXEC
+ Machine: EM_X86_64
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ Address: 0x1000
+ AddressAlign: 0x1000
+ Size: 4096
+ - Name: .text2
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ Address: 0x2000
+ AddressAlign: 0x1000
+ Size: 4096
+ Content: "DEADBEEF"
+ - Name: .text3
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ Address: 0x3000
+ AddressAlign: 0x1000
+ Size: 4096
+ProgramHeaders:
+ - Type: PT_LOAD
+ Flags: [ PF_X, PF_R ]
+ Sections:
+ - Section: .text
+ - Section: .text2
+ - Section: .text3
+
+# Make sure that when we remove a section we overwrite it with zeros
+# DATA: 0020000 00 00 00 00
+
+#CHECK: SectionHeaderCount: 6
+
+# CHECK: Sections [
+# CHECK: Section {
+# CHECK-NEXT: Index: 0
+# CHECK-NEXT: Name: (0)
+# CHECK-NEXT: Type: SHT_NULL (0x0)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 0
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 1
+# CHECK-NEXT: Name: .text
+# CHECK-NEXT: Type: SHT_PROGBITS
+# CHECK-NEXT: Flags [
+# CHECK-NEXT: SHF_ALLOC
+# CHECK-NEXT: SHF_EXECINSTR
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x1000
+# CHECK-NEXT: Offset: 0x1000
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 4096
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 2
+# CHECK-NEXT: Name: .text3
+# CHECK-NEXT: Type: SHT_PROGBITS (0x1)
+# CHECK-NEXT: Flags [
+# CHECK-NEXT: SHF_ALLOC
+# CHECK-NEXT: SHF_EXECINSTR
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x3000
+# CHECK-NEXT: Offset: 0x3000
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 4096
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 3
+# CHECK-NEXT: Name: .symtab
+# CHECK-NEXT: Type: SHT_SYMTAB (0x2)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 4
+# CHECK-NEXT: Info: 1
+# CHECK-NEXT: AddressAlignment: 8
+# CHECK-NEXT: EntrySize: 24
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 4
+# CHECK-NEXT: Name: .strtab
+# CHECK-NEXT: Type: SHT_STRTAB (0x3)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 1
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 5
+# CHECK-NEXT: Name: .shstrtab
+# CHECK-NEXT: Type: SHT_STRTAB (0x3)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 1
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: }
+# CHECK-NEXT: ]
+
+#CHECK: ProgramHeaders [
+#CHECK-NEXT: ProgramHeader {
+#CHECK-NEXT: Type: PT_LOAD (0x1)
+#CHECK-NEXT: Offset: 0x1000
+#CHECK-NEXT: VirtualAddress: 0x0
+#CHECK-NEXT: PhysicalAddress: 0x0
+#CHECK-NEXT: FileSize: 12288
+#CHECK-NEXT: MemSize: 12288
+#CHECK-NEXT: Flags [ (0x5)
+#CHECK-NEXT: PF_R (0x4)
+#CHECK-NEXT: PF_X (0x1)
+#CHECK-NEXT: ]
+#CHECK-NEXT: Alignment: 4096
+#CHECK-NEXT: }
+#CHECK-NEXT:]