Change how we iterate over relocations on ELF.

For COFF and MachO, sections semantically have relocations that apply to them.
That is not the case on ELF.

In relocatable objects (.o), a section with relocations in ELF has offsets to
another section where the relocations should be applied.

In dynamic objects and executables, relocations don't have an offset, they have
a virtual address. The section sh_info may or may not point to another section,
but that is not actually used for resolving the relocations.

This patch exposes that in the ObjectFile API. It has the following advantages:

* Most (all?) clients can handle this more efficiently. They will normally walk
all relocations, so doing an effort to iterate in a particular order doesn't
save time.

* llvm-readobj now prints relocations in the same way the native readelf does.

* probably most important, relocations that don't point to any section are now
visible. This is the case of relocations in the rela.dyn section. See the
updated relocation-executable.test for example.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182908 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 15 deletions

diff --git a/test/MC/ARM/eh-directive-section.s b/test/MC/ARM/eh-directive-section.s
index 5f5d1252f8..7c1f32ee39 100644
--- a/test/MC/ARM/eh-directive-section.s
+++ b/test/MC/ARM/eh-directive-section.s
@@ -60,13 +60,13 @@ func2:
 @-------------------------------------------------------------------------------
 @ CHECK:   Section {
 @ CHECK:     Name: .ARM.extab.TEST1
-@ CHECK:     Relocations [
-@ CHECK:       0x0 R_ARM_PREL31 __gxx_personality_v0 0x0
-@ CHECK:     ]
 @ CHECK:     SectionData (
 @ CHECK:       0000: 00000000 B0B0B000                    |........|
 @ CHECK:     )
 @ CHECK:   }
+@ CHECK:     Relocations [
+@ CHECK:       0x0 R_ARM_PREL31 __gxx_personality_v0 0x0
+@ CHECK:     ]
 
 
 @-------------------------------------------------------------------------------
@@ -85,15 +85,14 @@ func2:
 @ The second word should be relocated to the EHTAB entry in .ARM.extab.TEST1
 @ section.
 @-------------------------------------------------------------------------------
-@ CHECK:     Relocations [
-@ CHECK:       0x0 R_ARM_PREL31 .TEST1 0x0
-@ CHECK:       0x4 R_ARM_PREL31 .ARM.extab.TEST1 0x0
-@ CHECK:     ]
 @ CHECK:     SectionData (
 @ CHECK:       0000: 00000000 00000000                    |........|
 @ CHECK:     )
 @ CHECK:   }
-
+@ CHECK:     Relocations [
+@ CHECK:       0x0 R_ARM_PREL31 .TEST1 0x0
+@ CHECK:       0x4 R_ARM_PREL31 .ARM.extab.TEST1 0x0
+@ CHECK:     ]
 
 
 @-------------------------------------------------------------------------------
@@ -112,13 +111,13 @@ func2:
 @-------------------------------------------------------------------------------
 @ CHECK:   Section {
 @ CHECK:     Name: .ARM.extabTEST2
-@ CHECK:     Relocations [
-@ CHECK:       0x0 R_ARM_PREL31 __gxx_personality_v0 0x0
-@ CHECK:     ]
 @ CHECK:     SectionData (
 @ CHECK:       0000: 00000000 B0B0B000                    |........|
 @ CHECK:     )
 @ CHECK:   }
+@ CHECK:     Relocations [
+@ CHECK:       0x0 R_ARM_PREL31 __gxx_personality_v0 0x0
+@ CHECK:     ]
 
 
 @-------------------------------------------------------------------------------
@@ -137,15 +136,15 @@ func2:
 @ The second word should be relocated to the EHTAB entry in .ARM.extabTEST2
 @ section.
 @-------------------------------------------------------------------------------
-@ CHECK:     Relocations [
-@ CHECK:       0x0 R_ARM_PREL31 TEST2 0x0
-@ CHECK:       0x4 R_ARM_PREL31 .ARM.extabTEST2 0x0
-@ CHECK:     ]
 @ CHECK:     SectionData (
 @ CHECK:       0000: 00000000 00000000                    |........|
 @ CHECK:     )
 @ CHECK:   }
 @ CHECK: ]
+@ CHECK:     Relocations [
+@ CHECK:       0x0 R_ARM_PREL31 TEST2 0x0
+@ CHECK:       0x4 R_ARM_PREL31 .ARM.extabTEST2 0x0
+@ CHECK:     ]