[WebAssembly] Allow multivalue types in block signature operands

Summary:
Renames `ExprType` to the more apt `BlockType` and adds a variant for
multivalue blocks. Currently non-void blocks are only generated at the
end of functions where the block return type needs to agree with the
function return type, and that remains true for multivalue
blocks. That invariant means that the actual signature does not need
to be stored in the block signature `MachineOperand` because it can be
inferred by `WebAssemblyMCInstLower` from the return type of the
parent function. `WebAssemblyMCInstLower` continues to lower block
signature operands to immediates when possible but lowers multivalue
signatures to function type symbols. The AsmParser and Disassembler
are updated to handle multivalue block types as well.

Reviewers: aheejin, dschuff, aardappel

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68889

llvm-svn: 374933

3 files changed, 11 insertions, 18 deletions

diff --git a/llvm/tools/llvm-mc/Disassembler.cpp b/llvm/tools/llvm-mc/Disassembler.cpp
index e2af2e7f2e3..1ddbddfa184 100644
--- a/llvm/tools/llvm-mc/Disassembler.cpp
+++ b/llvm/tools/llvm-mc/Disassembler.cpp
@@ -17,6 +17,7 @@
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
 #include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCObjectFileInfo.h"
 #include "llvm/MC/MCRegisterInfo.h"
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSubtargetInfo.h"
@@ -129,13 +130,10 @@ static bool ByteArrayFromString(ByteArrayTy &ByteArray,
   return false;
 }
 
-int Disassembler::disassemble(const Target &T,
-                              const std::string &Triple,
-                              MCSubtargetInfo &STI,
-                              MCStreamer &Streamer,
-                              MemoryBuffer &Buffer,
-                              SourceMgr &SM,
-                              raw_ostream &Out) {
+int Disassembler::disassemble(const Target &T, const std::string &Triple,
+                              MCSubtargetInfo &STI, MCStreamer &Streamer,
+                              MemoryBuffer &Buffer, SourceMgr &SM,
+                              MCContext &Ctx, raw_ostream &Out) {
 
   std::unique_ptr<const MCRegisterInfo> MRI(T.createMCRegInfo(Triple));
   if (!MRI) {
@@ -149,9 +147,6 @@ int Disassembler::disassemble(const Target &T,
     return -1;
   }
 
-  // Set up the MCContext for creating symbols and MCExpr's.
-  MCContext Ctx(MAI.get(), MRI.get(), nullptr);
-
   std::unique_ptr<const MCDisassembler> DisAsm(
     T.createMCDisassembler(STI, Ctx));
   if (!DisAsm) {
diff --git a/llvm/tools/llvm-mc/Disassembler.h b/llvm/tools/llvm-mc/Disassembler.h
index 11b685233ab..dcd8c279c91 100644
--- a/llvm/tools/llvm-mc/Disassembler.h
+++ b/llvm/tools/llvm-mc/Disassembler.h
@@ -22,17 +22,15 @@ class MemoryBuffer;
 class Target;
 class raw_ostream;
 class SourceMgr;
+class MCContext;
 class MCSubtargetInfo;
 class MCStreamer;
 
 class Disassembler {
 public:
-  static int disassemble(const Target &T,
-                         const std::string &Triple,
-                         MCSubtargetInfo &STI,
-                         MCStreamer &Streamer,
-                         MemoryBuffer &Buffer,
-                         SourceMgr &SM,
+  static int disassemble(const Target &T, const std::string &Triple,
+                         MCSubtargetInfo &STI, MCStreamer &Streamer,
+                         MemoryBuffer &Buffer, SourceMgr &SM, MCContext &Ctx,
                          raw_ostream &Out);
 };
 
diff --git a/llvm/tools/llvm-mc/llvm-mc.cpp b/llvm/tools/llvm-mc/llvm-mc.cpp
index 97d507028c1..c23740a3094 100644
--- a/llvm/tools/llvm-mc/llvm-mc.cpp
+++ b/llvm/tools/llvm-mc/llvm-mc.cpp
@@ -517,8 +517,8 @@ int main(int argc, char **argv) {
     break;
   }
   if (disassemble)
-    Res = Disassembler::disassemble(*TheTarget, TripleName, *STI, *Str,
-                                    *Buffer, SrcMgr, Out->os());
+    Res = Disassembler::disassemble(*TheTarget, TripleName, *STI, *Str, *Buffer,
+                                    SrcMgr, Ctx, Out->os());
 
   // Keep output if no errors.
   if (Res == 0) {