replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[WebAssembly][MC] Allow empty assembly functions 

Differential Revision: https://reviews.llvm.org/D66434

llvm-svn: 369292
This commit is contained in:
Sam Clegg 2019-08-19 19:04:54 +00:00
parent 1a3fdaf6a6
commit 19bf637eb1
2 changed files with 23 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
llvm/lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp
View File

@ -489,6 +489,7 @@ public:
if (pop(Name, Block))
return true;
} else if (Name == "end_function") {
ensureLocals(getStreamer());
CurrentState = EndFunction;
if (pop(Name, Function) || ensureEmptyNestingStack())
return true;
@ -758,6 +759,19 @@ public:
return true; // We didn't process this directive.
}
// Called either when the first instruction is parsed of the function ends.
void ensureLocals(MCStreamer &Out) {
if (CurrentState == FunctionStart) {
// We haven't seen a .local directive yet. The streamer requires locals to
// be encoded as a prelude to the instructions, so emit an empty list of
// locals here.
auto &TOut = reinterpret_cast<WebAssemblyTargetStreamer &>(
*Out.getTargetStreamer());
TOut.emitLocal(SmallVector<wasm::ValType, 0>());
CurrentState = FunctionLocals;
}
}
bool MatchAndEmitInstruction(SMLoc IDLoc, unsigned & /*Opcode*/,
OperandVector &Operands, MCStreamer &Out,
uint64_t &ErrorInfo,
@ -768,15 +782,7 @@ public:
MatchInstructionImpl(Operands, Inst, ErrorInfo, MatchingInlineAsm);
switch (MatchResult) {
case Match_Success: {
if (CurrentState == FunctionStart) {
// This is the first instruction in a function, but we haven't seen
// a .local directive yet. The streamer requires locals to be encoded
// as a prelude to the instructions, so emit an empty list of locals
// here.
auto &TOut = reinterpret_cast<WebAssemblyTargetStreamer &>(
*Out.getTargetStreamer());
TOut.emitLocal(SmallVector<wasm::ValType, 0>());
}
ensureLocals(Out);
// Fix unknown p2align operands.
auto Align = WebAssembly::GetDefaultP2AlignAny(Inst.getOpcode());
if (Align != -1U) {

8
llvm/test/MC/WebAssembly/basic-assembly.s
View File

@ -2,6 +2,11 @@
# Check that it converts to .o without errors, but don't check any output:
# RUN: llvm-mc -triple=wasm32-unknown-unknown -filetype=obj -mattr=+atomics,+unimplemented-simd128,+nontrapping-fptoint,+exception-handling -o %t.o < %s
empty_func:
.functype empty_func () -> ()
end_function
test0:
# Test all types:
.functype test0 (i32, i64) -> (i32)
@ -111,6 +116,9 @@ test0:
.globaltype __stack_pointer, i32
# CHECK: .text
# CHECK-LABEL: empty_func:
# CHECK-NEXT: .functype empty_func () -> ()
# CHECK-NEXT: end_function
# CHECK-LABEL: test0:
# CHECK-NEXT: .functype test0 (i32, i64) -> (i32)
# CHECK-NEXT: .eventtype __cpp_exception i32