[WebAssembly] Added default stack-only instruction mode for MC.

Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll

tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*

Reviewers: dschuff, sunfish

Subscribers: jfb, llvm-commits, aheejin, eraman, jgravelle-google, sbc100

Differential Revision: https://reviews.llvm.org/D50568

llvm-svn: 339474

1 files changed, 28 insertions, 8 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
index 596264f0132..c6aa0a77fff 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
@@ -169,45 +169,62 @@ void WebAssemblyAsmPrinter::EmitInstruction(const MachineInstr *MI) {
 
   switch (MI->getOpcode()) {
   case WebAssembly::ARGUMENT_I32:
+  case WebAssembly::ARGUMENT_I32_S:
   case WebAssembly::ARGUMENT_I64:
+  case WebAssembly::ARGUMENT_I64_S:
   case WebAssembly::ARGUMENT_F32:
+  case WebAssembly::ARGUMENT_F32_S:
   case WebAssembly::ARGUMENT_F64:
+  case WebAssembly::ARGUMENT_F64_S:
   case WebAssembly::ARGUMENT_v16i8:
+  case WebAssembly::ARGUMENT_v16i8_S:
   case WebAssembly::ARGUMENT_v8i16:
+  case WebAssembly::ARGUMENT_v8i16_S:
   case WebAssembly::ARGUMENT_v4i32:
+  case WebAssembly::ARGUMENT_v4i32_S:
   case WebAssembly::ARGUMENT_v2i64:
+  case WebAssembly::ARGUMENT_v2i64_S:
   case WebAssembly::ARGUMENT_v4f32:
+  case WebAssembly::ARGUMENT_v4f32_S:
   case WebAssembly::ARGUMENT_v2f64:
+  case WebAssembly::ARGUMENT_v2f64_S:
     // These represent values which are live into the function entry, so there's
     // no instruction to emit.
     break;
   case WebAssembly::FALLTHROUGH_RETURN_I32:
+  case WebAssembly::FALLTHROUGH_RETURN_I32_S:
   case WebAssembly::FALLTHROUGH_RETURN_I64:
+  case WebAssembly::FALLTHROUGH_RETURN_I64_S:
   case WebAssembly::FALLTHROUGH_RETURN_F32:
+  case WebAssembly::FALLTHROUGH_RETURN_F32_S:
   case WebAssembly::FALLTHROUGH_RETURN_F64:
+  case WebAssembly::FALLTHROUGH_RETURN_F64_S:
   case WebAssembly::FALLTHROUGH_RETURN_v16i8:
+  case WebAssembly::FALLTHROUGH_RETURN_v16i8_S:
   case WebAssembly::FALLTHROUGH_RETURN_v8i16:
+  case WebAssembly::FALLTHROUGH_RETURN_v8i16_S:
   case WebAssembly::FALLTHROUGH_RETURN_v4i32:
+  case WebAssembly::FALLTHROUGH_RETURN_v4i32_S:
   case WebAssembly::FALLTHROUGH_RETURN_v2i64:
+  case WebAssembly::FALLTHROUGH_RETURN_v2i64_S:
   case WebAssembly::FALLTHROUGH_RETURN_v4f32:
-  case WebAssembly::FALLTHROUGH_RETURN_v2f64: {
+  case WebAssembly::FALLTHROUGH_RETURN_v4f32_S:
+  case WebAssembly::FALLTHROUGH_RETURN_v2f64:
+  case WebAssembly::FALLTHROUGH_RETURN_v2f64_S: {
     // These instructions represent the implicit return at the end of a
-    // function body. The operand is always a pop.
-    assert(MFI->isVRegStackified(MI->getOperand(0).getReg()));
-
+    // function body. Always pops one value off the stack.
     if (isVerbose()) {
-      OutStreamer->AddComment("fallthrough-return: $pop" +
-                              Twine(MFI->getWARegStackId(
-                                  MFI->getWAReg(MI->getOperand(0).getReg()))));
+      OutStreamer->AddComment("fallthrough-return-value");
       OutStreamer->AddBlankLine();
     }
     break;
   }
   case WebAssembly::FALLTHROUGH_RETURN_VOID:
+  case WebAssembly::FALLTHROUGH_RETURN_VOID_S:
     // This instruction represents the implicit return at the end of a
     // function body with no return value.
     if (isVerbose()) {
-      OutStreamer->AddComment("fallthrough-return");
+      OutStreamer->AddComment("fallthrough-return-void");
       OutStreamer->AddBlankLine();
     }
     break;
@@ -248,6 +265,9 @@ bool WebAssemblyAsmPrinter::PrintAsmOperand(const MachineInstr *MI,
       OS << MO.getImm();
       return false;
     case MachineOperand::MO_Register:
+      // FIXME: only opcode that still contains registers, as required by
+      // MachineInstr::getDebugVariable().
+      assert(MI->getOpcode() == WebAssembly::INLINEASM);
       OS << regToString(MO);
       return false;
     case MachineOperand::MO_GlobalAddress: