[PATCH] D17733: [ELF] Fix reading of PC values of FDEs

[Rui Ueyama via llvm-commits]

ruiu added inline comments.

================
Comment at: ELF/OutputSections.cpp:669-670
@@ -668,16 +668,4 @@
 typename EhFrameHeader<ELFT>::uintX_t
 EhFrameHeader<ELFT>::getFdePc(uintX_t EhVA, const FdeData &F) {
-  const endianness E = ELFT::TargetEndianness;
-  assert((F.Enc & 0xF0) != DW_EH_PE_datarel);
-
-  uintX_t FdeOff = EhVA + F.Off + 8;
-  switch (F.Enc & 0xF) {
-  case DW_EH_PE_udata2:
-  case DW_EH_PE_sdata2:
-    return FdeOff + read16<E>(F.PCRel);
-  case DW_EH_PE_udata4:
-  case DW_EH_PE_sdata4:
-    return FdeOff + read32<E>(F.PCRel);
-  case DW_EH_PE_udata8:
-  case DW_EH_PE_sdata8:
-    return FdeOff + read64<E>(F.PCRel);
+  auto Read = [=](uint8_t Size) -> uint64_t {
+    const endianness E = ELFT::TargetEndianness;
----------------
Do you have to use lambda? It seems you can write without it in a more regular way.

  const endianness E = ELFT::TargetEndianness;

  int Size = F.Enc & 0x7;
  if (Size == DW_EH_PE_absptr)
    Size = sizeof(uintX_t) == 8 ? DW_EH_PE_udata8 : DW_EH_PE_udata4;

  uintX_t V;
  switch (Size) {
  case DW_EH_PE_udata2:
    V = read16<E>(F.PCRel);
  case DW_EH_PE_udata4:
    V = read32<E>(F.PCRel);
  case DW_EH_PE_udata8:
    V = read64<E>(F.PCRel);
  default:
    fatal("unknown FDE size encoding");
  }

  switch (F.Enc & 0x70) {
  case DW_EH_PE_absptr:
    return V;
  case DW_EH_PE_pcrel:
    return V + EhVA + F.Off + 8;
  default:
    fatal("unknown FDE size relative encoding");
  }



Repository:
  rL LLVM

http://reviews.llvm.org/D17733