[WebAssembly] Switch to MC for instruction printing.

This encompasses several changes which are all interconnected:
 - Use the MC framework for printing almost all instructions.
 - AsmStrings are now live.
 - This introduces an indirection between LLVM vregs and WebAssembly registers,
   and a new pass, WebAssemblyRegNumbering, for computing a basic the mapping.
   This addresses some basic issues with argument registers and unused registers.
 - The way ARGUMENT instructions are handled no longer generates redundant
   get_local+set_local for every argument.

This also changes the assembly syntax somewhat; most notably, MC's printing
use sigils on label names, so those are no longer present, and push/pop now
have a sigil to keep them unambiguous.

The usage of set_local/get_local/$push/$pop will continue to evolve
significantly. This patch is just one step of a larger change.

llvm-svn: 252858

1 files changed, 8 insertions, 4 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrCall.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrCall.td
index 82a42f564ab..d175b6ae626 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrCall.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrCall.td
@@ -23,9 +23,11 @@ def : I<(outs), (ins i64imm:$amt1, i64imm:$amt2),
 
 multiclass CALL<WebAssemblyRegClass vt> {
   def CALL_#vt : I<(outs vt:$dst), (ins global:$callee, variable_ops),
-                   [(set vt:$dst, (WebAssemblycall1 (WebAssemblywrapper tglobaladdr:$callee)))]>;
+                   [(set vt:$dst, (WebAssemblycall1 (WebAssemblywrapper tglobaladdr:$callee)))],
+                   "call $callee, $dst">;
   def CALL_INDIRECT_#vt : I<(outs vt:$dst), (ins I32:$callee, variable_ops),
-                            [(set vt:$dst, (WebAssemblycall1 I32:$callee))]>;
+                            [(set vt:$dst, (WebAssemblycall1 I32:$callee))],
+                            "call_indirect $callee, $dst">;
 }
 let Uses = [SP32, SP64], isCall = 1 in {
   defm : CALL<I32>;
@@ -34,9 +36,11 @@ let Uses = [SP32, SP64], isCall = 1 in {
   defm : CALL<F64>;
 
   def CALL_VOID : I<(outs), (ins global:$callee, variable_ops),
-                    [(WebAssemblycall0 (WebAssemblywrapper tglobaladdr:$callee))]>;
+                    [(WebAssemblycall0 (WebAssemblywrapper tglobaladdr:$callee))],
+                    "call $callee">;
   def CALL_INDIRECT_VOID : I<(outs), (ins I32:$callee, variable_ops),
-                             [(WebAssemblycall0 I32:$callee)]>;
+                             [(WebAssemblycall0 I32:$callee)],
+                             "call_indirect $callee">;
 } // Uses = [SP32,SP64], isCall = 1
 
 /*