[ELF] Linkerscript: simplify DATA_SEGMENT_ALIGN evaluation

[grimar]

Summary

As was suggested by Rafael, we can simplify the evaluation of DATA_SEGMENT_ALIGN
just to simple align. That way it will work exactly like we have in non-script case.

This is not really neccessary to support DATA_SEGMENT_RELRO_END, but
since them are relative, I think it is a good start point.

[• rafael]

LGTM

[ruiu]

lld/trunk/ELF/LinkerScript.cpp

815–816

Please merge the two lines -- return alignTo(Dot, E(Dot));

[ruiu]

lld/trunk/ELF/LinkerScript.cpp

814–816

So actually this can be return [=](uint64_t Dot) { return alignTo(Dot, E(Dot)); }.

[grimar]

lld/trunk/ELF/LinkerScript.cpp

814–816

r276768

lld/trunk/ELF/LinkerScript.cpp

if (Tok == "CONSTANT") {
     return [=](uint64_t Dot) { return getConstant(Tok); };
   }
   if (Tok == "DATA_SEGMENT_ALIGN") {
     expect("(");
     Expr E = readExpr();
     expect(",");
     readExpr();
     expect(")");
     return [=](uint64_t Dot) -> uint64_t {
       uint64_t Val = E(Dot);
-      return alignTo(Dot, Val) + (Dot & (Val - 1));
+      return alignTo(Dot, Val);
     };
   }
   if (Tok == "DATA_SEGMENT_END") {
     expect("(");
     expect(".");
     expect(")");
     return [](uint64_t Dot) { return Dot; };
   }

lld/trunk/test/ELF/linkerscript/linkerscript-locationcounter.s

 # CHECK-NEXT: }
 # CHECK-NEXT: Section {
 # CHECK-NEXT:   Index:
 # CHECK-NEXT:   Name: .datasegmentalign
 # CHECK-NEXT:   Type: SHT_PROGBITS
 # CHECK-NEXT:   Flags [
 # CHECK-NEXT:     SHF_ALLOC
 # CHECK-NEXT:   ]
-# CHECK-NEXT:   Address: 0x26008
+# CHECK-NEXT:   Address: 0x26000
 # CHECK-NEXT:   Offset:
 # CHECK-NEXT:   Size:
 # CHECK-NEXT:   Link:
 # CHECK-NEXT:   Info:
 # CHECK-NEXT:   AddressAlignment:
 # CHECK-NEXT:   EntrySize:
 # CHECK-NEXT: }