[PATCH] D95005: Revert "[WebAssembly] call_indirect issues table number relocs"

[Sam Clegg via Phabricator via llvm-commits]

sbc100 created this revision.
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This reverts commit 418df4a6ab35d343cc0f2608c90a73dd9b8d0ab1 <https://reviews.llvm.org/rG418df4a6ab35d343cc0f2608c90a73dd9b8d0ab1>.

This change broke emscripten tests, I believe because it started
generating 5-byte a wide table index in the call_indirect instruction.
Neither v8 nor wabt seem to be able to handle that.  The spec
currently says that this is single 0x0 byte and:

"In future versions of WebAssembly, the zero byte occurring in the
encoding of the call_indirectcall_indirect instruction may be used to
index additional tables."

So we need to revisit this change.  For backwards compat I guess
we need to guarantee that __indirect_function_table is always at
address zero.   We could also consider making this a single-byte
relocation with and assert if have more than 127 tables (for now).


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D95005

Files:
  lld/test/wasm/call-indirect.ll
  lld/test/wasm/compress-relocs.ll
  lld/test/wasm/shared.ll
  llvm/lib/MC/WasmObjectWriter.cpp
  llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp
  llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyInstPrinter.cpp
  llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.h
  llvm/lib/Target/WebAssembly/WebAssemblyFastISel.cpp
  llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
  llvm/lib/Target/WebAssembly/WebAssemblyInstrCall.td
  llvm/lib/Target/WebAssembly/WebAssemblyMCInstLower.cpp
  llvm/test/CodeGen/WebAssembly/function-pointer64.ll
  llvm/test/CodeGen/WebAssembly/multivalue.ll
  llvm/test/MC/WebAssembly/basic-assembly.s
  llvm/test/MC/WebAssembly/call-indirect-relocs.s
  llvm/test/MC/WebAssembly/reloc-code.ll
  llvm/test/MC/WebAssembly/tail-call-encodings.s
  llvm/test/MC/WebAssembly/type-index.s
  llvm/test/MC/WebAssembly/weak-alias.s

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