[llvm-objdump] Support nonzero section addresses in addSymbolizer

The previous calculations seem to have assumed that the section address would be zero.
This is true for relocatable object files, but certainly not for linked files like shared libraries.

Fixed the calculations to make them identical to the "real" `getInstruction` call below & added a regression test.

Reviewed By: scott.linder, simon_tatham

Differential Revision: https://reviews.llvm.org/D135430

llvm/test/tools/llvm-objdump/AMDGPU/elf-disassemble-symbolize-operands.yaml

@@ -1,6 +1,13 @@
-# RUN: yaml2obj %s -o %t
-# RUN: llvm-objdump %t -d --symbolize-operands --no-show-raw-insn --no-leading-addr | \
-# RUN:   FileCheck %s
+# RUN: rm -rf %t
+# RUN: %split-file %s %t
+
+# RUN: yaml2obj %t/zero-secaddr.yml -o %t/zero-secaddr
+# RUN: llvm-objdump %t/zero-secaddr -d --symbolize-operands\
+# RUN:  --no-show-raw-insn --no-leading-addr | FileCheck %s
+
+# RUN: yaml2obj %t/nonzero-secaddr.yml -o %t/nonzero-secaddr
+# RUN: llvm-objdump %t/nonzero-secaddr -d --symbolize-operands\
+# RUN:  --no-show-raw-insn --no-leading-addr | FileCheck %s
 
 ## Expect to find the branch labels.
 # CHECK: <break_cond_is_arg>:
@@ -29,9 +36,9 @@
 #   loopexit:
 #     ret void
 #   }
-#   
+#
 #   declare void @llvm.amdgcn.raw.buffer.store.f32(float, <4 x i32>, i32, i32, i32 immarg) #0
-#   
+#
 #   attributes #0 = { nounwind writeonly }
 #
 # I compiled it to a relocatable ELF:
@@ -43,7 +50,12 @@
 #   obj2yaml a.elf
 #
 # then manually removed the BB0_1 etc local symbols.
+#
+# Note that there are two copies of the file:
+#   - One as a relocatable object file (zero section addresses)
+#   - One as a shared object file (non-zero section addresses)
 
+#--- zero-secaddr.yml
 --- !ELF
 FileHeader:
   Class:           ELFCLASS64
@@ -87,3 +99,53 @@ Symbols:
     Binding:         STB_GLOBAL
     Size:            0x5C
 ...
+
+#--- nonzero-secaddr.yml
+--- !ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_DYN
+  Machine:         EM_AMDGPU
+  Flags:           [ EF_AMDGPU_MACH_AMDGCN_GFX1030 ]
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    Address:         0x1000
+    AddressAlign:    0x4
+    Content:         00008CBF0000FDBB81020236810385BE800384BE8102847D6AC10689040082BF7E077E88058105817E047E8A080088BF0500887D7E060787070404886A3C87BEF7FF88BF000070E000000104F4FF82BF7E047E880000FDBB1E2080BE
+  - Name:            .AMDGPU.config
+    Type:            SHT_PROGBITS
+    Address:         0x2000
+    AddressAlign:    0x1
+    Content:         48B80000000000004CB800000000000060B800000000000004000000000000000800000000000000
+  - Name:            .note.GNU-stack
+    Type:            SHT_PROGBITS
+    Address:         0x3000
+    AddressAlign:    0x1
+  - Name:            .note
+    Type:            SHT_NOTE
+    Address:         0x4000
+    AddressAlign:    0x4
+    Notes:
+      - Name:            AMD
+        Desc:            616D6467636E2D756E6B6E6F776E2D6C696E75782D676E752D67667831303330
+        Type:            NT_FREEBSD_PROCSTAT_GROUPS
+  - Type:            SectionHeaderTable
+    Sections:
+      - Name:            .strtab
+      - Name:            .shstrtab
+      - Name:            .text
+      - Name:            .AMDGPU.config
+      - Name:            .note.GNU-stack
+      - Name:            .note
+      - Name:            .symtab
+Symbols:
+  - Name:            break_cond_is_arg
+    Type:            STT_FUNC
+    Section:         .text
+    Binding:         STB_GLOBAL
+    Size:            0x5C
+    Value:           0x1000
+...

llvm/tools/llvm-objdump/llvm-objdump.cpp

@@ -1190,8 +1190,9 @@ static void addSymbolizer(
   for (size_t Index = 0; Index != Bytes.size();) {
     MCInst Inst;
     uint64_t Size;
-    ArrayRef<uint8_t> ThisBytes = Bytes.slice(Index - SectionAddr);
-    DisAsm->getInstruction(Inst, Size, ThisBytes, Index, nulls());
+    ArrayRef<uint8_t> ThisBytes = Bytes.slice(Index);
+    const uint64_t ThisAddr = SectionAddr + Index;
+    DisAsm->getInstruction(Inst, Size, ThisBytes, ThisAddr, nulls());
     if (Size == 0)
       Size = std::min<uint64_t>(ThisBytes.size(),
                                 DisAsm->suggestBytesToSkip(ThisBytes, Index));