[Test] Underscored simplify_cfg_simplify_argument.

Use underscores rather than hyphens so that text editors understand the
name as a single word.

Author: nate-chandler

lib/SILOptimizer/Transforms/SimplifyCFG.cpp

@@ -3793,7 +3793,7 @@ namespace swift::test {
 /// Dumps:
 /// - nothing
 static FunctionTest SimplifyCFGSimplifyArgument(
-    "simplify-cfg-simplify-argument",
+    "simplify_cfg_simplify_argument",
     [](auto &function, auto &arguments, auto &test) {
       auto *passToRun = cast<SILFunctionTransform>(createSimplifyCFG());
       passToRun->injectPassManager(test.getPassManager());

test/SILOptimizer/simplify_cfg_ossa_bbargs.sil

@@ -180,7 +180,7 @@ bb4:
 // CHECK-LABEL: } // end sil function 'test_simplify_args8'
 sil [ossa] @test_simplify_args8 : $@convention(thin) (@guaranteed Klass) -> () {
 bb0(%0 : @guaranteed $Klass):
-  specify_test "simplify-cfg-simplify-argument @block[1] 0"
+  specify_test "simplify_cfg_simplify_argument @block[1] 0"
   %1 = enum $FakeOptional<Klass>, #FakeOptional.some!enumelt, %0 : $Klass
   br bb1(%1 : $FakeOptional<Klass>)
 
@@ -200,7 +200,7 @@ bb3:
 // CHECK-LABEL: } // end sil function 'test_simplify_args9'
 sil [ossa] @test_simplify_args9 : $@convention(thin) (@owned Klass) -> () {
 bb0(%0 : @owned $Klass):
-  specify_test "simplify-cfg-simplify-argument @block[1] 0"
+  specify_test "simplify_cfg_simplify_argument @block[1] 0"
   %1 = enum $FakeOptional<Klass>, #FakeOptional.some!enumelt, %0 : $Klass
   br bb1(%1 : $FakeOptional<Klass>)
 
@@ -223,7 +223,7 @@ bb3:
 // CHECK: return
 sil [ossa] @test_dont_remove_mandatory_dead_args : $@convention(thin) (@guaranteed AnyKlass) -> () {
 bb0(%0 : @guaranteed $AnyKlass):
-  specify_test "simplify-cfg-simplify-argument @block[1] 0"
+  specify_test "simplify_cfg_simplify_argument @block[1] 0"
   checked_cast_br AnyKlass in %0 : $AnyKlass to Klass, bb1, bb2
 
 bb1(%1 : @guaranteed $Klass):
@@ -244,7 +244,7 @@ bb3(%4 : $Builtin.Int32):
 // CHECK-LABEL: } // end sil function 'test_simplify_enum_arg_owned'
 sil [ossa] @test_simplify_enum_arg_owned : $@convention(thin) (@owned Klass) -> () {
 bb0(%0 : @owned $Klass):
-  specify_test "simplify-cfg-simplify-argument @block[1] 0"
+  specify_test "simplify_cfg_simplify_argument @block[1] 0"
   %1 = enum $FakeOptional<Klass>, #FakeOptional.some!enumelt, %0 : $Klass
   %c = copy_value %1 : $FakeOptional<Klass>
   br bb1(%1 : $FakeOptional<Klass>)
@@ -270,7 +270,7 @@ bb3:
 // CHECK-LABEL: } // end sil function 'test_simplify_enum_arg_guaranteed1'
 sil [ossa] @test_simplify_enum_arg_guaranteed1 : $@convention(thin) (@owned Klass) -> () {
 bb0(%0 : @owned $Klass):
-  specify_test "simplify-cfg-simplify-argument @block[1] 0"
+  specify_test "simplify_cfg_simplify_argument @block[1] 0"
   %b = begin_borrow %0 : $Klass
   %1 = enum $FakeOptional<Klass>, #FakeOptional.some!enumelt, %b : $Klass
   %c = copy_value %1 : $FakeOptional<Klass>
@@ -293,7 +293,7 @@ bb2:
 // CHECK: bb1([[ARG:%.*]] : @guaranteed $NonTrivialStruct)
 sil [ossa] @test_simplify_enum_arg_guaranteed2 : $@convention(thin) (@owned Klass) -> () {
 bb0(%0 : @owned $Klass):
-  specify_test "simplify-cfg-simplify-argument @block[1] 0"
+  specify_test "simplify_cfg_simplify_argument @block[1] 0"
   %b = begin_borrow %0 : $Klass
   %1 = struct $NonTrivialStruct(%b : $Klass) 
   %c = copy_value %1 : $NonTrivialStruct