[all-commits] [llvm/llvm-project] bf142f: MCObjectStreamer: assign MCSymbols in the dummy fr...

[James Y Knight via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: bf142fc43347d8a35a71f46f7dda7e2a0a992e0d
      https://github.com/llvm/llvm-project/commit/bf142fc43347d8a35a71f46f7dda7e2a0a992e0d
  Author: James Y Knight <jyknight at google.com>
  Date:   2019-11-16 (Sat, 16 Nov 2019)

  Changed paths:
    M llvm/include/llvm/MC/MCELFStreamer.h
    M llvm/include/llvm/MC/MCObjectStreamer.h
    M llvm/lib/MC/MCELFStreamer.cpp
    M llvm/lib/MC/MCObjectStreamer.cpp
    M llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
    M llvm/test/MC/AsmParser/assembler-expressions.s

  Log Message:
  -----------
  MCObjectStreamer: assign MCSymbols in the dummy fragment to offset 0.

In MCObjectStreamer, when there is no current fragment, initially
symbols are created in a "pending" state and assigned to a dummy
empty fragment.

Previously, they were not being assigned an offset, and thus
evaluateAbsolute would fail if trying to evaluate an expression 'a -
b', where both 'a' and 'b' were in this pending state.

Also slightly refactored the EmitLabel overload which takes an
MCFragment for clarity.

Fixes: https://llvm.org/PR41825

Differential Revision: https://reviews.llvm.org/D70062