[sanitizer] Remove numeric values from -asan-use-after-return flag. (NFC)

[kda]

Summary

for issue: https://github.com/google/sanitizers/issues/1394

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

static cl::opt<uint32_t> ClMaxInlinePoisoningSize(
     cl::Hidden, cl::init(64));
 
 static cl::opt<AsanDetectStackUseAfterReturnMode> ClUseAfterReturn(
     "asan-use-after-return",
     cl::desc("Sets the mode of detection for stack-use-after-return."),
     cl::values(
         clEnumValN(AsanDetectStackUseAfterReturnMode::Never, "never",
                    "Never detect stack use after return."),
-        clEnumValN(AsanDetectStackUseAfterReturnMode::Never,
-                   "0", // only needed to keep unit tests passing
-                   "Redundant with 'never'."),
         clEnumValN(
             AsanDetectStackUseAfterReturnMode::Runtime, "runtime",
             "Detect stack use after return if "
             "binary flag 'ASAN_OPTIONS=detect_stack_use_after_return' is set."),
-        clEnumValN(AsanDetectStackUseAfterReturnMode::Runtime,
-                   "1", // only needed to keep unit tests passing
-                   "redundant with 'runtime'."),
         clEnumValN(AsanDetectStackUseAfterReturnMode::Always, "always",
-                   "Always detect stack use after return."),
-        clEnumValN(AsanDetectStackUseAfterReturnMode::Always,
-                   "2", // only needed to keep unit tests passing
                    "Always detect stack use after return.")),
     cl::Hidden, cl::init(AsanDetectStackUseAfterReturnMode::Runtime));
 
 static cl::opt<bool> ClRedzoneByvalArgs("asan-redzone-byval-args",
                                         cl::desc("Create redzones for byval "
                                                  "arguments (extra copy "
                                                  "required)"), cl::Hidden,
                                         cl::init(true));

llvm/test/DebugInfo/X86/asan_debug_info.ll

-; RUN: opt < %s -asan -asan-module -asan-use-after-return=0 -S -enable-new-pm=0 | \
+; RUN: opt < %s -asan -asan-module -asan-use-after-return=never -S -enable-new-pm=0 | \
 ; RUN:   llc -O0 -filetype=obj - -o - | \
 ; RUN:   llvm-dwarfdump - | FileCheck %s
-; RUN: opt < %s -passes=asan-pipeline -asan-use-after-return=0 -S | \
+; RUN: opt < %s -passes=asan-pipeline -asan-use-after-return=never -S | \
 ; RUN:   llc -O0 -filetype=obj - -o - | \
 ; RUN:   llvm-dwarfdump - | FileCheck %s
 
 ; For this test case, ASan used to produce IR which resulted in the following
 ; DWARF (at -O0):
 ;
 ;   DW_TAG_subprogram
 ;     DW_AT_low_pc    (0x0000000000000000)

llvm/test/Instrumentation/AddressSanitizer/debug_info.ll

-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-return=0 -S | FileCheck %s
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=0 -S | FileCheck %s
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-return=never -S | FileCheck %s
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=never -S | FileCheck %s
 
 ; Checks that llvm.dbg.declare instructions are updated
 ; accordingly as we merge allocas.
 
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
 @G = global [32 x i8] zeroinitializer, align 32, !dbg !0, !type !6

llvm/test/Instrumentation/AddressSanitizer/fake-stack.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=0 -S | FileCheck %s --check-prefixes=CHECK,NEVER
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=1 -S | FileCheck %s --check-prefixes=CHECK,RUNTIME
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=2 -S | FileCheck %s --check-prefixes=CHECK,ALWAYS
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=never -S | FileCheck %s --check-prefixes=CHECK,NEVER
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=runtime -S | FileCheck %s --check-prefixes=CHECK,RUNTIME
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-return=always -S | FileCheck %s --check-prefixes=CHECK,ALWAYS
 target datalayout = "e-i64:64-f80:128-s:64-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
 declare void @Foo(i8*)
 
 define void @Empty() uwtable sanitize_address {
 ; CHECK-LABEL: @Empty(
 ; CHECK-NEXT:  entry:

llvm/test/Instrumentation/AddressSanitizer/lifetime-throw.ll

 ; Test handling of llvm.lifetime intrinsics with C++ exceptions.
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-scope -asan-use-after-return=0 -S | FileCheck %s
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-scope -asan-use-after-return=0 -S | FileCheck %s
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-scope -asan-use-after-return=never -S | FileCheck %s
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-scope -asan-use-after-return=never -S | FileCheck %s
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
 %struct.ABC = type { i32 }
 
 $_ZN3ABCD2Ev = comdat any
 $_ZTS3ABC = comdat any

llvm/test/Instrumentation/AddressSanitizer/lifetime.ll

 ; Test handling of llvm.lifetime intrinsics.
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-scope -asan-use-after-return=0 -S | FileCheck %s --check-prefixes=CHECK,CHECK-DEFAULT
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-scope -asan-use-after-return=0 -S | FileCheck %s --check-prefixes=CHECK,CHECK-DEFAULT
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-scope -asan-use-after-return=0 -asan-instrument-dynamic-allocas=0 -S | FileCheck %s --check-prefixes=CHECK,CHECK-NO-DYNAMIC
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-scope -asan-use-after-return=0 -asan-instrument-dynamic-allocas=0 -S | FileCheck %s --check-prefixes=CHECK,CHECK-NO-DYNAMIC
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-scope -asan-use-after-return=never -S | FileCheck %s --check-prefixes=CHECK,CHECK-DEFAULT
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-scope -asan-use-after-return=never -S | FileCheck %s --check-prefixes=CHECK,CHECK-DEFAULT
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-after-scope -asan-use-after-return=never -asan-instrument-dynamic-allocas=0 -S | FileCheck %s --check-prefixes=CHECK,CHECK-NO-DYNAMIC
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-after-scope -asan-use-after-return=never -asan-instrument-dynamic-allocas=0 -S | FileCheck %s --check-prefixes=CHECK,CHECK-NO-DYNAMIC
 
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
 declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) nounwind
 declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) nounwind
 
 define void @lifetime_no_size() sanitize_address {