[WebAssembly] Implement more WebAssembly binary encoding.

This changes locals from being declared by the emitLocal hook in
WebAssemblyTargetStreamer, rather than with an instruction. After exploring
the infastructure in LLVM more, this seems to make more sense since
declaring locals doesn't use an encoded opcode.

This also adds more 0xd opcodes, type encodings, and miscellaneous
binary encoding bits.

llvm-svn: 285040

1 files changed, 15 insertions, 10 deletions

diff --git a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp
index d740b0adc7a..f7183241f9f 100644
--- a/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp
+++ b/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCCodeEmitter.cpp
@@ -60,7 +60,8 @@ void WebAssemblyMCCodeEmitter::encodeInstruction(
   uint64_t Start = OS.tell();
 
   uint64_t Binary = getBinaryCodeForInstr(MI, Fixups, STI);
-  encodeULEB128(Binary, OS);
+  assert(Binary < UINT8_MAX && "Multi-byte opcodes not supported yet");
+  OS << uint8_t(Binary);
 
   const MCInstrDesc &Desc = MCII.get(MI.getOpcode());
   for (unsigned i = 0, e = MI.getNumOperands(); i < e; ++i) {
@@ -68,16 +69,20 @@ void WebAssemblyMCCodeEmitter::encodeInstruction(
     if (MO.isReg()) {
       /* nothing to encode */
     } else if (MO.isImm()) {
-      assert(i < Desc.getNumOperands() &&
-             "Unexpected integer immediate as a non-fixed operand");
-      assert(Desc.TSFlags == 0 &&
-             "WebAssembly variable_ops integer ops don't use TSFlags");
-      const MCOperandInfo &Info = Desc.OpInfo[i];
-      if (Info.OperandType == WebAssembly::OPERAND_I32IMM) {
-        encodeSLEB128(int32_t(MO.getImm()), OS);
-      } else if (Info.OperandType == WebAssembly::OPERAND_I64IMM) {
-        encodeSLEB128(int64_t(MO.getImm()), OS);
+      if (i < Desc.getNumOperands()) {
+        assert(Desc.TSFlags == 0 &&
+               "WebAssembly non-variable_ops don't use TSFlags");
+        const MCOperandInfo &Info = Desc.OpInfo[i];
+        if (Info.OperandType == WebAssembly::OPERAND_I32IMM) {
+          encodeSLEB128(int32_t(MO.getImm()), OS);
+        } else if (Info.OperandType == WebAssembly::OPERAND_I64IMM) {
+          encodeSLEB128(int64_t(MO.getImm()), OS);
+        } else {
+          encodeULEB128(uint64_t(MO.getImm()), OS);
+        }
       } else {
+        assert(Desc.TSFlags == (WebAssemblyII::VariableOpIsImmediate |
+                                WebAssemblyII::VariableOpImmediateIsLabel));
         encodeULEB128(uint64_t(MO.getImm()), OS);
       }
     } else if (MO.isFPImm()) {