[BOLT] Review nits

- fix spelling in MarkRAStates
- improve negate-ra-state.s test
- improve pacret-split-funcs.s test

Author: bgergely0

bolt/lib/Passes/MarkRAStates.cpp

@@ -73,7 +73,7 @@ bool MarkRAStates::runOnFunction(BinaryFunction &BF) {
           BF.setIgnored();
           return false;
         }
-        // The signing instruction itself is unsinged, but the next will be
+        // The signing instruction itself is unsigned, the next will be
         // signed.
         BC.MIB->setRAUnsigned(Inst);
       } else if (BC.MIB->isPAuthOnLR(Inst)) {

bolt/test/AArch64/negate-ra-state.s

@@ -1,11 +1,16 @@
 # Checking that .cfi-negate_ra_state directives are emitted in the same location as in the input in the case of no optimizations.
 
+# The foo and bar functions are a pair, with the first signing the return address,
+# and the second authenticating it. We have a tailcall between the two.
+# This is testing that BOLT can handle functions starting in signed RA state.
+
 # RUN: llvm-mc -filetype=obj -triple aarch64-unknown-unknown %s -o %t.o
 # RUN: %clang %cflags  %t.o -o %t.exe -Wl,-q
 # RUN: llvm-bolt %t.exe -o %t.exe.bolt --no-threads --print-all | FileCheck %s --check-prefix=CHECK-BOLT
 
 # Check that the negate-ra-state at the start of bar is not discarded.
 # If it was discarded, MarkRAState would report bar as having inconsistent RAStates.
+# This is testing the handling of initialRAState on the BinaryFunction.
 # CHECK-BOLT-NOT: BOLT-INFO: inconsistent RAStates in function foo
 # CHECK-BOLT-NOT: BOLT-INFO: inconsistent RAStates in function bar
 
@@ -69,8 +74,3 @@ bar:
   ret
   .cfi_endproc
   .size   bar, .-bar
-
-  .global _start
-  .type _start, %function
-_start:
-  b foo

bolt/test/AArch64/pacret-split-funcs.s

@@ -36,16 +36,17 @@
 foo:
 .cfi_startproc
 .entry_bb:
+# FDATA: 1 foo #.entry_bb# 10
      paciasp
     .cfi_negate_ra_state     // indicating that paciasp changed the RA state to signed
-# FDATA: 1 foo #.entry_bb# 10
     cmp x0, #0
     b.eq .Lcold_bb1
+.Lfallthrough:
     autiasp
     .cfi_negate_ra_state     // indicating that autiasp changed the RA state to unsigned
     ret
     .cfi_negate_ra_state     // ret has unsigned RA state, but the next inst (autiasp) has signed RA state
-.Lcold_bb1:
+.Lcold_bb1:                  // split point
     autiasp
     .cfi_negate_ra_state     // indicating that autiasp changed the RA state to unsigned
     ret