[WebAssembly] Misc. fixes in cfg-stackify-eh.ll

[aheejin]

Summary

• Fix preds comments
• Delete nonexistent attributes in instructions (They used to exist in clang-generated files, but I removed most of them to make the tests tidy. We have only nounwind and noreturn left here.)
• Add missing Function Attrs comments in function declarations
  
  None of these affect test function semantics or test results for now.

llvm/test/CodeGen/WebAssembly/cfg-stackify-eh.ll

entry:
   %o = alloca %class.Object, align 1
   invoke void @foo()
           to label %invoke.cont unwind label %ehcleanup
 
 invoke.cont:                                      ; preds = %entry
   call void @llvm.memcpy.p0i8.p0i8.i32(i8* %a, i8* %b, i32 100, i1 false)
   call void @llvm.memmove.p0i8.p0i8.i32(i8* %a, i8* %b, i32 100, i1 false)
   call void @llvm.memset.p0i8.i32(i8* %a, i8 0, i32 100, i1 false)
-  %call = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %o) #1
+  %call = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %o)
   ret void
 
 ehcleanup:                                        ; preds = %entry
   %0 = cleanuppad within none []
-  %call2 = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %o) #1 [ "funclet"(token %0) ]
+  %call2 = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %o) [ "funclet"(token %0) ]
   cleanupret from %0 unwind to caller
 }
 
 ; Tests if 'try' marker is placed correctly. In this test, 'try' should be
 ; placed before the call to 'nothrow_i32' and not between the call to
 ; 'nothrow_i32' and 'fun', because the return value of 'nothrow_i32' is
 ; stackified and pushed onto the stack to be consumed by the call to 'fun'.
 

 
 catch.dispatch:                                   ; preds = %for.body
   %0 = catchswitch within none [label %catch.start] unwind to caller
 
 catch.start:                                      ; preds = %catch.dispatch
   %1 = catchpad within %0 [i8* bitcast ({ i8*, i8* }* @_ZTI7MyClass to i8*)]
   %2 = call i8* @llvm.wasm.get.exception(token %1)
   %3 = call i32 @llvm.wasm.get.ehselector(token %1)
-  %4 = call i32 @llvm.eh.typeid.for(i8* bitcast ({ i8*, i8* }* @_ZTI7MyClass to i8*)) #3
+  %4 = call i32 @llvm.eh.typeid.for(i8* bitcast ({ i8*, i8* }* @_ZTI7MyClass to i8*))
   %matches = icmp eq i32 %3, %4
   br i1 %matches, label %catch, label %rethrow
 
 catch:                                            ; preds = %catch.start
-  %5 = call i8* @__cxa_get_exception_ptr(i8* %2) #3 [ "funclet"(token %1) ]
+  %5 = call i8* @__cxa_get_exception_ptr(i8* %2) [ "funclet"(token %1) ]
   %6 = bitcast i8* %5 to %class.MyClass*
   %call = call %class.MyClass* @_ZN7MyClassC2ERKS_(%class.MyClass* %e, %class.MyClass* dereferenceable(4) %6) [ "funclet"(token %1) ]
-  %7 = call i8* @__cxa_begin_catch(i8* %2) #3 [ "funclet"(token %1) ]
+  %7 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
   %x = getelementptr inbounds %class.MyClass, %class.MyClass* %e, i32 0, i32 0
   %8 = load i32, i32* %x, align 4
   invoke void @quux(i32 %8) [ "funclet"(token %1) ]
           to label %invoke.cont2 unwind label %ehcleanup
 
 invoke.cont2:                                     ; preds = %catch
-  %call3 = call %class.MyClass* @_ZN7MyClassD2Ev(%class.MyClass* %e) #3 [ "funclet"(token %1) ]
+  %call3 = call %class.MyClass* @_ZN7MyClassD2Ev(%class.MyClass* %e) [ "funclet"(token %1) ]
   call void @__cxa_end_catch() [ "funclet"(token %1) ]
   catchret from %1 to label %for.inc
 
 rethrow:                                          ; preds = %catch.start
-  call void @llvm.wasm.rethrow() #6 [ "funclet"(token %1) ]
+  call void @llvm.wasm.rethrow() [ "funclet"(token %1) ]
   unreachable
 
 for.inc:                                          ; preds = %invoke.cont2, %for.body
   %inc = add nsw i32 %i.0, 1
   br label %for.cond
 
 ehcleanup:                                        ; preds = %catch
   %9 = cleanuppad within %1 []
-  %call4 = call %class.MyClass* @_ZN7MyClassD2Ev(%class.MyClass* %e) #3 [ "funclet"(token %9) ]
+  %call4 = call %class.MyClass* @_ZN7MyClassD2Ev(%class.MyClass* %e) [ "funclet"(token %9) ]
   invoke void @__cxa_end_catch() [ "funclet"(token %9) ]
           to label %invoke.cont6 unwind label %terminate7
 
 invoke.cont6:                                     ; preds = %ehcleanup
   cleanupret from %9 unwind to caller
 
 for.end:                                          ; preds = %for.cond
   ret void
 
 terminate7:                                       ; preds = %ehcleanup
   %10 = cleanuppad within %9 []
   %11 = call i8* @llvm.wasm.get.exception(token %10)
-  call void @__clang_call_terminate(i8* %11) #7 [ "funclet"(token %10) ]
+  call void @__clang_call_terminate(i8* %11) [ "funclet"(token %10) ]
   unreachable
 }
 
 ; Tests if CFGStackify's removeUnnecessaryInstrs() removes unnecessary branches
 ; correctly. The code is in the form below, where 'br' is unnecessary because
 ; after running the 'try' body the control flow will fall through to bb2 anyway.
 
 ; bb0:

 
 catch.dispatch:                                   ; preds = %for.body, %entry
   %0 = catchswitch within none [label %catch.start] unwind to caller
 
 catch.start:                                      ; preds = %catch.dispatch
   %1 = catchpad within %0 [i8* null]
   %2 = call i8* @llvm.wasm.get.exception(token %1)
   %3 = call i32 @llvm.wasm.get.ehselector(token %1)
-  %4 = call i8* @__cxa_begin_catch(i8* %2) #2 [ "funclet"(token %1) ]
+  %4 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
   call void @__cxa_end_catch() [ "funclet"(token %1) ]
   catchret from %1 to label %try.cont
 
 try.cont:                                         ; preds = %catch.start, %for.end
   ret void
 }
 
 ; void foo();

 catch.dispatch:                                   ; preds = %invoke.cont
   %0 = catchswitch within none [label %catch.start] unwind label %catch.dispatch3
 
 ; CHECK: catch
 catch.start:                                      ; preds = %catch.dispatch
   %1 = catchpad within %0 [i8* null]
   %2 = call i8* @llvm.wasm.get.exception(token %1)
   %3 = call i32 @llvm.wasm.get.ehselector(token %1)
-  %4 = call i8* @__cxa_begin_catch(i8* %2) #2 [ "funclet"(token %1) ]
+  %4 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
   invoke void @__cxa_end_catch() [ "funclet"(token %1) ]
           to label %invoke.cont2 unwind label %catch.dispatch3
 
 catch.dispatch3:                                  ; preds = %catch.start, %catch.dispatch, %entry
   %5 = catchswitch within none [label %catch.start4] unwind to caller
 
 catch.start4:                                     ; preds = %catch.dispatch3
   %6 = catchpad within %5 [i8* null]
   %7 = call i8* @llvm.wasm.get.exception(token %6)
   %8 = call i32 @llvm.wasm.get.ehselector(token %6)
-  %9 = call i8* @__cxa_begin_catch(i8* %7) #2 [ "funclet"(token %6) ]
+  %9 = call i8* @__cxa_begin_catch(i8* %7) [ "funclet"(token %6) ]
   call void @__cxa_end_catch() [ "funclet"(token %6) ]
   catchret from %6 to label %try.cont8
 
-try.cont8:                                        ; preds = %invoke.cont, %invoke.cont2, %catch.start4
+try.cont8:                                        ; preds = %invoke.cont2, %catch.start4, %invoke.cont
   ret void
 
 invoke.cont2:                                     ; preds = %catch.start
   catchret from %1 to label %try.cont8
 }
 
 ; Here an exception is semantically contained in a loop. 'ehcleanup' BB belongs
 ; to the exception, but does not belong to the loop (because it does not have a
for.body:                                         ; preds = %for.cond
   %cmp1 = icmp eq i32 %i.0, %div
   br i1 %cmp1, label %if.then, label %for.inc
 
 if.then:                                          ; preds = %for.body
   %call = invoke i32 @baz()
           to label %invoke.cont unwind label %ehcleanup
 
 invoke.cont:                                      ; preds = %if.then
-  %call2 = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %t) #4
+  %call2 = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %t)
   ret i32 %call
 
 for.inc:                                          ; preds = %for.body
   %inc = add nsw i32 %i.0, 1
   br label %for.cond
 
 ehcleanup:                                        ; preds = %if.then
   %0 = cleanuppad within none []
-  %call3 = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %t) #4 [ "funclet"(token %0) ]
+  %call3 = call %class.Object* @_ZN6ObjectD2Ev(%class.Object* %t) [ "funclet"(token %0) ]
   cleanupret from %0 unwind to caller
 }
 
 ; This crashed when updating EHPadStack within fixCallUniwindMismatch had a bug.
 ; This should not crash and try-delegate has to be created around 'call @baz',
 ; because the initial TRY placement for 'call @quux' was done before 'call @baz'
 ; because 'call @baz''s return value is stackified.
 

 declare void @foo()
 declare void @bar()
 declare i32 @baz()
 declare i32 @qux(i32)
 declare void @quux(i32)
 declare void @fun(i32)
 ; Function Attrs: nounwind
 declare void @nothrow(i32) #0
+; Function Attrs: nounwind
 declare i32 @nothrow_i32() #0
 
 ; Function Attrs: nounwind
 declare %class.Object* @_ZN6ObjectD2Ev(%class.Object* returned) #0
 @_ZTI7MyClass = external constant { i8*, i8* }, align 4
 ; Function Attrs: nounwind
 declare %class.MyClass* @_ZN7MyClassD2Ev(%class.MyClass* returned) #0
 ; Function Attrs: nounwind
 declare %class.MyClass* @_ZN7MyClassC2ERKS_(%class.MyClass* returned, %class.MyClass* dereferenceable(4)) #0
 
 declare i32 @__gxx_wasm_personality_v0(...)
-declare i8* @llvm.wasm.get.exception(token)
-declare i32 @llvm.wasm.get.ehselector(token)
-declare void @llvm.wasm.rethrow()
-declare i32 @llvm.eh.typeid.for(i8*)
+; Function Attrs: nounwind
+declare i8* @llvm.wasm.get.exception(token) #0
+; Function Attrs: nounwind
+declare i32 @llvm.wasm.get.ehselector(token) #0
+; Function Attrs: noreturn
+declare void @llvm.wasm.rethrow() #1
+; Function Attrs: nounwind
+declare i32 @llvm.eh.typeid.for(i8*) #0
+
 declare i8* @__cxa_begin_catch(i8*)
 declare void @__cxa_end_catch()
 declare i8* @__cxa_get_exception_ptr(i8*)
 declare void @__clang_call_terminate(i8*)
 declare void @_ZSt9terminatev()
 ; Function Attrs: nounwind
 declare void @llvm.memcpy.p0i8.p0i8.i32(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i32, i1 immarg) #0
 ; Function Attrs: nounwind
 declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i1 immarg) #0
 ; Function Attrs: nounwind
 declare void @llvm.memset.p0i8.i32(i8* nocapture writeonly, i8, i32, i1 immarg) #0
 
 attributes #0 = { nounwind }
+attributes #1 = { noreturn }