[llvm-branch-commits] [llvm-branch] r369359 - Merging r369199:

[Hans Wennborg via llvm-branch-commits]

Author: hans
Date: Tue Aug 20 02:56:16 2019
New Revision: 369359

URL: http://llvm.org/viewvc/llvm-project?rev=369359&view=rev
Log:
Merging r369199:
------------------------------------------------------------------------
r369199 | yhs | 2019-08-18 00:12:00 +0200 (Sun, 18 Aug 2019) | 26 lines

[BPF] Fix bpf llvm-objdump issues.

Commit https://reviews.llvm.org/D57939 ("[DWARF] Refactor
RelocVisitor and fix computation of SHT_RELA-typed relocation entries)
made a change for relocation resolution when operating
on an object file.

The change unfortunately broke BPF as given SymbolValue (S) and
Addent (A), previously relocation is resolved to
    S + A
and after the change, it is resolved to
    S

This patch fixed the issue by resolving relocation correctly.

It looks not all relocation resolution reaches here and I did not
trace down exactly when. But I do find if the object file includes
codes in two different ELF sections than default ".text",
the above bug will be triggered.

This patch included a trivial two function source code to
demonstrate this issue. The relocation for .debug_loc is resolved
incorrectly due to this and llvm-objdump cannot display source
annotated assembly.

Differential Revision: https://reviews.llvm.org/D66372
------------------------------------------------------------------------

Added:
    llvm/branches/release_90/test/CodeGen/BPF/objdump_two_funcs.ll
      - copied unchanged from r369199, llvm/trunk/test/CodeGen/BPF/objdump_two_funcs.ll
Modified:
    llvm/branches/release_90/   (props changed)
    llvm/branches/release_90/lib/Object/RelocationResolver.cpp

Propchange: llvm/branches/release_90/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Tue Aug 20 02:56:16 2019
@@ -1,3 +1,3 @@
 /llvm/branches/Apple/Pertwee:110850,110961
 /llvm/branches/type-system-rewrite:133420-134817
-/llvm/trunk:155241,366431,366481,366487,366527,366570,366660,366868,366925,367019,367030,367062,367084,367124,367215,367292,367304,367306,367314,367340-367341,367394,367396,367398,367403,367417,367662,367750,367753,367846-367847,367898,367941,368004,368230,368300,368315,368324,368477-368478,368517-368519,368554,368572,368873,369011,369026,369084,369097,369168
+/llvm/trunk:155241,366431,366481,366487,366527,366570,366660,366868,366925,367019,367030,367062,367084,367124,367215,367292,367304,367306,367314,367340-367341,367394,367396,367398,367403,367417,367662,367750,367753,367846-367847,367898,367941,368004,368230,368300,368315,368324,368477-368478,368517-368519,368554,368572,368873,369011,369026,369084,369097,369168,369199

Modified: llvm/branches/release_90/lib/Object/RelocationResolver.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_90/lib/Object/RelocationResolver.cpp?rev=369359&r1=369358&r2=369359&view=diff
==============================================================================
--- llvm/branches/release_90/lib/Object/RelocationResolver.cpp (original)
+++ llvm/branches/release_90/lib/Object/RelocationResolver.cpp Tue Aug 20 02:56:16 2019
@@ -90,9 +90,9 @@ static bool supportsBPF(uint64_t Type) {
 static uint64_t resolveBPF(RelocationRef R, uint64_t S, uint64_t A) {
   switch (R.getType()) {
   case ELF::R_BPF_64_32:
-    return S & 0xFFFFFFFF;
+    return (S + A) & 0xFFFFFFFF;
   case ELF::R_BPF_64_64:
-    return S;
+    return S + A;
   default:
     llvm_unreachable("Invalid relocation type");
   }