Reland "[llvm-objcopy] Add support for nested and overlapping segments"

I didn't initialize a pointer to be nullptr that I needed to.

This change adds support for nested and even overlapping segments. This means
that PT_PHDR, PT_GNU_RELRO, PT_TLS, and PT_DYNAMIC can be supported properly.

Differential Revision: https://reviews.llvm.org/D36558

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313682 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 455 insertions, 0 deletions

diff --git a/test/tools/llvm-objcopy/adjacent-segments.test b/test/tools/llvm-objcopy/adjacent-segments.test
new file mode 100644
index 00000000000..45f4224f7e8
--- /dev/null
+++ b/test/tools/llvm-objcopy/adjacent-segments.test
@@ -0,0 +1,62 @@
+# This test tests that if two non-overlapping segments are right next to each
+# other no problems arise.
+
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy %t %t2
+# RUN: llvm-readobj --program-headers %t2 | FileCheck %s
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_EXEC
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            24
+  - Name:            .text2
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x10
+    Size:            16
+ProgramHeaders:
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text2
+
+#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: 24
+#CHECK-NEXT:    MemSize: 24
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x1020
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 16
+#CHECK-NEXT:    MemSize: 16
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 16
+#CHECK-NEXT:  }
+#CHECK-NEXT:]
diff --git a/test/tools/llvm-objcopy/identical-segments.test b/test/tools/llvm-objcopy/identical-segments.test
new file mode 100644
index 00000000000..7273416da7a
--- /dev/null
+++ b/test/tools/llvm-objcopy/identical-segments.test
@@ -0,0 +1,82 @@
+# This test tests that if two possible parent segments have the same offset that
+# they're disambiguated based on their original index. This ensures that cycles
+# do not occur.
+
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy %t %t2
+# RUN: llvm-readobj --program-headers %t2 | FileCheck %s
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_EXEC
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text2
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+ProgramHeaders:
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text2
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text
+      - Section: .text2
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text
+      - Section: .text2
+
+#CHECK:     ProgramHeaders [
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x2000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 4096
+#CHECK-NEXT:    MemSize: 4096
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x1000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 8192
+#CHECK-NEXT:    MemSize: 8192
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x1000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 8192
+#CHECK-NEXT:    MemSize: 8192
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:]
diff --git a/test/tools/llvm-objcopy/overlap-chain.test b/test/tools/llvm-objcopy/overlap-chain.test
new file mode 100644
index 00000000000..a084abbb5ba
--- /dev/null
+++ b/test/tools/llvm-objcopy/overlap-chain.test
@@ -0,0 +1,117 @@
+# This test tests how ParentSegment is set for Segments. In particular this test
+# tests that if a chain of parents forms, the offsets are chosen for parents
+# first despite the order of the list. It also tests multiple branches of the
+# code that assigns parents.
+
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy %t %t2
+# RUN: llvm-readobj -program-headers %t2 | FileCheck %s
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_EXEC
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text2
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text3
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text4
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text5
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+ProgramHeaders:
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text
+      - Section: .text2
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text4
+      - Section: .text5
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text3
+      - Section: .text4
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text2
+      - Section: .text3
+
+#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: 8192
+#CHECK-NEXT:    MemSize: 8192
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x4000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 8192
+#CHECK-NEXT:    MemSize: 8192
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x3000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 8192
+#CHECK-NEXT:    MemSize: 8192
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x2000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 8192
+#CHECK-NEXT:    MemSize: 8192
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:]
diff --git a/test/tools/llvm-objcopy/pt-phdr.test b/test/tools/llvm-objcopy/pt-phdr.test
new file mode 100644
index 00000000000..336ce769770
--- /dev/null
+++ b/test/tools/llvm-objcopy/pt-phdr.test
@@ -0,0 +1,71 @@
+# This test simply tests a simple but common real world example of overlapping
+# segments.
+
+# RUN: llvm-objcopy %p/Inputs/pt-phdr.elf %t
+# RUN: llvm-readobj -program-headers %t | FileCheck %s
+
+#CHECK: ProgramHeaders [
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_PHDR
+#CHECK-NEXT:    Offset: 0x40
+#CHECK-NEXT:    VirtualAddress: 0x200040
+#CHECK-NEXT:    PhysicalAddress: 0x200040
+#CHECK-NEXT:    FileSize: 280
+#CHECK-NEXT:    MemSize: 280
+#CHECK-NEXT:    Flags [
+#CHECK-NEXT:      PF_R
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 8
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD
+#CHECK-NEXT:    Offset: 0x0
+#CHECK-NEXT:    VirtualAddress: 0x200000
+#CHECK-NEXT:    PhysicalAddress: 0x200000
+#CHECK-NEXT:    FileSize: 344
+#CHECK-NEXT:    MemSize: 344
+#CHECK-NEXT:    Flags [
+#CHECK-NEXT:      PF_R
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD
+#CHECK-NEXT:    Offset: 0x1000
+#CHECK-NEXT:    VirtualAddress: 0x201000
+#CHECK-NEXT:    PhysicalAddress: 0x201000
+#CHECK-NEXT:    FileSize: 1
+#CHECK-NEXT:    MemSize: 1
+#CHECK-NEXT:    Flags [
+#CHECK-NEXT:      PF_R
+#CHECK-NEXT:      PF_X
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD
+#CHECK-NEXT:    Offset: 0x2000
+#CHECK-NEXT:    VirtualAddress: 0x202000
+#CHECK-NEXT:    PhysicalAddress: 0x202000
+#CHECK-NEXT:    FileSize: 14
+#CHECK-NEXT:    MemSize: 14
+#CHECK-NEXT:    Flags [
+#CHECK-NEXT:      PF_R
+#CHECK-NEXT:      PF_W
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_GNU_STACK (0x6474E551)
+#CHECK-NEXT:    Offset: 0x0
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 0
+#CHECK-NEXT:    MemSize: 0
+#CHECK-NEXT:    Flags [
+#CHECK-NEXT:      PF_R
+#CHECK-NEXT:      PF_W
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 0
+#CHECK-NEXT:  }
+#CHECK-NEXT:]
diff --git a/test/tools/llvm-objcopy/triple-overlap.test b/test/tools/llvm-objcopy/triple-overlap.test
new file mode 100644
index 00000000000..503a9075f4a
--- /dev/null
+++ b/test/tools/llvm-objcopy/triple-overlap.test
@@ -0,0 +1,123 @@
+# This test tests that each segment is assigned a canonical parent segment.
+# Importantly if two segments could be the parent segment of a segment this test
+# should cover the case where a new parent replaces the old parent and the case
+# where an old parent is not replaced by a new parent.
+
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy %t %t2
+# RUN: llvm-readobj --program-headers %t2 | FileCheck %s
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_EXEC
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text2
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text3
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text4
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+  - Name:            .text5
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x1000
+    Size:            4096
+ProgramHeaders:
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text4
+      - Section: .text5
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text3
+      - Section: .text4
+      - Section: .text5
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text
+      - Section: .text2
+      - Section: .text3
+      - Section: .text4
+      - Section: .text5
+  - Type: PT_LOAD
+    Flags: [ PF_X, PF_R ]
+    Sections:
+      - Section: .text2
+      - Section: .text3
+      - Section: .text4
+      - Section: .text5
+
+#CHECK:     ProgramHeaders [
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x4000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 8192
+#CHECK-NEXT:    MemSize: 8192
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x3000
+#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:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x1000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 20480
+#CHECK-NEXT:    MemSize: 20480
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:  ProgramHeader {
+#CHECK-NEXT:    Type: PT_LOAD (0x1)
+#CHECK-NEXT:    Offset: 0x2000
+#CHECK-NEXT:    VirtualAddress: 0x0
+#CHECK-NEXT:    PhysicalAddress: 0x0
+#CHECK-NEXT:    FileSize: 16384
+#CHECK-NEXT:    MemSize: 16384
+#CHECK-NEXT:    Flags [ (0x5)
+#CHECK-NEXT:      PF_R (0x4)
+#CHECK-NEXT:      PF_X (0x1)
+#CHECK-NEXT:    ]
+#CHECK-NEXT:    Alignment: 4096
+#CHECK-NEXT:  }
+#CHECK-NEXT:]