[WebAssembly] Fix assembly printing of br_table

[aheejin]

Summary

In `br_table's stack version asm string, \t was missing.

[aardappel]

test/CodeGen/WebAssembly/stack-insts.ll

9 ↗

(On Diff #170459)

If this is the only thing this file is testing, is "stack-inst.ll" not a bit generic sounding for what it actually does? Either we intend to add more stack instruction format testing to this file, or it should have a more specific name?

[aheejin]

test/CodeGen/WebAssembly/stack-insts.ll

9 ↗

(On Diff #170459)

First I tried to create a .s test to test with llvm-mc so we can only test the parsing and printing, but it looks like [[ https://bugs.llvm.org/show_bug.cgi?id=39384 | br_table is not supported in WebAssemblyAsmParser ]] now. So I made this file, because all other .ll tests in this directory use non-stack version of instructions. The reason I named this file name stack-insts.ll was I thought maybe there will be cases we want to test misc. things for stack version of instructions, in which case we can add them to this file. But if you think for now this file should have more specific name, I think that also makes sense too.

[aardappel]

test/CodeGen/WebAssembly/stack-insts.ll

9 ↗

(On Diff #170459)

No, just an observation, it's fine if we want to add more tests.
Btw, hadn't seen that bug, feel free to assign them to me in the future.

[aheejin]

rebase

llvm/trunk/lib/Target/WebAssembly/WebAssemblyInstrControl.td

def BR_TABLE_I32 : NI<(outs), (ins I32:$index, variable_ops),
                       [(WebAssemblybr_table I32:$index)], "false",
                       "br_table \t$index", 0x0e> {
   let TSFlags{0} = 1;
   let TSFlags{1} = 1;
 }
 let BaseName = "BR_TABLE_I32" in
 def BR_TABLE_I32_S : NI<(outs), (ins variable_ops),
                         [], "true",
-                        "br_table", 0x0e> {
+                        "br_table \t", 0x0e> {
   let TSFlags{0} = 1;
   let TSFlags{1} = 1;
 }
 let isCodeGenOnly = 1 in
 def BR_TABLE_I64 : NI<(outs), (ins I64:$index, variable_ops),
                       [(WebAssemblybr_table I64:$index)], "false",
                       "br_table \t$index"> {
   let TSFlags{0} = 1;
   let TSFlags{1} = 1;
 }
 let BaseName = "BR_TABLE_I64" in
 def BR_TABLE_I64_S : NI<(outs), (ins variable_ops),
                         [], "true",
-                        "br_table"> {
+                        "br_table \t"> {
   let TSFlags{0} = 1;
   let TSFlags{1} = 1;
 }
 } // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
 
 // This is technically a control-flow instruction, since all it affects is the
 // IP.
 defm NOP : NRI<(outs), (ins), [], "nop", 0x01>;

llvm/trunk/test/CodeGen/WebAssembly/stack-insts.ll

+; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -disable-block-placement -verify-machineinstrs | FileCheck %s
+
+target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
+target triple = "wasm32-unknown-unknown"
+
+declare void @foo0()
+declare void @foo1()
+
+; Tests if br_table is printed correctly with a tab.
+; CHECK-LABEL: test0:
+; CHECK-NOT: br_table0, 1, 0, 1, 0
+; CHECK: br_table 0, 1, 0, 1, 0
+define void @test0(i32 %n) {
+entry:
+  switch i32 %n, label %sw.epilog [
+    i32 0, label %sw.bb
+    i32 1, label %sw.bb.1
+    i32 2, label %sw.bb
+    i32 3, label %sw.bb.1
+  ]
+
+sw.bb:                                            ; preds = %entry, %entry
+  tail call void @foo0()
+  br label %sw.epilog
+
+sw.bb.1:                                          ; preds = %entry, %entry
+  tail call void @foo1()
+  br label %sw.epilog
+
+sw.epilog:                                        ; preds = %entry, %sw.bb, %sw.bb.1
+  ret void
+}