Revert "Emit DW_OP_lit0/1 for constant boolean values" (llvm#156172)

Reverts llvm#155539

Failing on buildbots with:
```
Step 7 (test-build-stage1-unified-tree-check-all) failure: test (failure)
******************** TEST 'LLVM :: DebugInfo/debug-bool-const-location.ll' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
/home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/build/stage1/bin/llc /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/llvm-project/llvm/test/DebugInfo/debug-bool-const-location.ll -O3 -filetype=obj -o - | /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/build/stage1/bin/llvm-dwarfdump - | /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/build/stage1/bin/FileCheck /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/llvm-project/llvm/test/DebugInfo/debug-bool-const-location.ll # RUN: at line 2
+ /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/build/stage1/bin/llc /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/llvm-project/llvm/test/DebugInfo/debug-bool-const-location.ll -O3 -filetype=obj -o -
+ /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/build/stage1/bin/llvm-dwarfdump -
+ /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/build/stage1/bin/FileCheck /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/llvm-project/llvm/test/DebugInfo/debug-bool-const-location.ll
/home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/llvm-project/llvm/test/DebugInfo/debug-bool-const-location.ll:7:10: error: CHECK: expected string not found in input
; CHECK: {{.*}} DW_OP_lit0
         ^
<stdin>:27:54: note: scanning from here
 [0x0000000000000018, 0x0000000000000020): DW_OP_lit1, DW_OP_stack_value
                                                     ^
<stdin>:28:41: note: possible intended match here
 [0x0000000000000020, 0x0000000000000034): DW_OP_reg3 X3)
                                        ^

Input file: <stdin>
Check file: /home/buildbots/llvm-external-buildbots/workers/ppc64le-lld-multistage-test/ppc64le-lld-multistage-test/llvm-project/llvm/test/DebugInfo/debug-bool-const-location.ll

-dump-input=help explains the following input dump.

Input was:
<<<<<<
           .
           .
           .
          22:  DW_AT_decl_line (5) 
          23:  DW_AT_external (true) 
          24:  
          25: 0x0000003f: DW_TAG_variable 
          26:  DW_AT_location (0x00000000:  
          27:  [0x0000000000000018, 0x0000000000000020): DW_OP_lit1, DW_OP_stack_value 
check:7'0                                                          X~~~~~~~~~~~~~~~~~~~ error: no match found
          28:  [0x0000000000000020, 0x0000000000000034): DW_OP_reg3 X3) 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
check:7'1                                             ?                  possible intended match
          29:  DW_AT_name ("arg") 
check:7'0     ~~~~~~~~~~~~~~~~~~~~
          30:  DW_AT_decl_file ("test") 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~
          31:  DW_AT_decl_line (5) 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~
          32:  DW_AT_type (0x0000004f "bool") 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          33:  
check:7'0     ~
           .
```

Author: Michael137

llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp

@@ -3111,10 +3111,8 @@ void DwarfDebug::emitDebugLocValue(const AsmPrinter &AP, const DIBasicType *BT,
                             &AP](const DbgValueLocEntry &Entry,
                                  DIExpressionCursor &Cursor) -> bool {
     if (Entry.isInt()) {
-      if (BT && (BT->getEncoding() == dwarf::DW_ATE_boolean))
-        DwarfExpr.addBooleanConstant(Entry.getInt());
-      else if (BT && (BT->getEncoding() == dwarf::DW_ATE_signed ||
-                      BT->getEncoding() == dwarf::DW_ATE_signed_char))
+      if (BT && (BT->getEncoding() == dwarf::DW_ATE_signed ||
+                 BT->getEncoding() == dwarf::DW_ATE_signed_char))
         DwarfExpr.addSignedConstant(Entry.getInt());
       else
         DwarfExpr.addUnsignedConstant(Entry.getInt());

llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp

@@ -194,15 +194,6 @@ void DwarfExpression::addStackValue() {
     emitOp(dwarf::DW_OP_stack_value);
 }
 
-void DwarfExpression::addBooleanConstant(int64_t Value) {
-  assert(isImplicitLocation() || isUnknownLocation());
-  LocationKind = Implicit;
-  if (Value == 0)
-    emitOp(dwarf::DW_OP_lit0);
-  else
-    emitOp(dwarf::DW_OP_lit1);
-}
-
 void DwarfExpression::addSignedConstant(int64_t Value) {
   assert(isImplicitLocation() || isUnknownLocation());
   LocationKind = Implicit;

llvm/lib/CodeGen/AsmPrinter/DwarfExpression.h

@@ -229,9 +229,6 @@ class DwarfExpression {
   /// This needs to be called last to commit any pending changes.
   void finalize();
 
-  /// Emit a boolean constant.
-  void addBooleanConstant(int64_t Value);
-
   /// Emit a signed constant.
   void addSignedConstant(int64_t Value);