[llvm-branch-commits] [llvm] e91eb89 - [Debug-Info] guard attribute generating under strict dwarf.

[Chen Zheng via llvm-branch-commits]

Author: Chen Zheng
Date: 2021-04-24T21:34:42-04:00
New Revision: e91eb89cc97d077c8bbae2c28749304d005511cd

URL: https://github.com/llvm/llvm-project/commit/e91eb89cc97d077c8bbae2c28749304d005511cd
DIFF: https://github.com/llvm/llvm-project/commit/e91eb89cc97d077c8bbae2c28749304d005511cd.diff

LOG: [Debug-Info] guard attribute generating under strict dwarf.

Conflicts:
	llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h

Added: 
    

Modified: 
    llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
    llvm/test/DebugInfo/PowerPC/strict-dwarf.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
index aca831a535a19..3a961ab47f6df 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
@@ -18,6 +18,7 @@
 #include "llvm/ADT/Optional.h"
 #include "llvm/CodeGen/AsmPrinter.h"
 #include "llvm/CodeGen/DIE.h"
+#include "llvm/Target/TargetMachine.h"
 #include <string>
 
 namespace llvm {
@@ -79,6 +80,12 @@ class DwarfUnit : public DIEUnit {
   template <typename T>
   void addAttribute(DIEValueList &Die, dwarf::Attribute Attribute,
                     dwarf::Form Form, T &&Value) {
+    // For strict DWARF mode, only generate attributes available to current
+    // DWARF version.
+    if (Attribute != 0 && Asm->TM.Options.DebugStrictDwarf &&
+        DD->getDwarfVersion() < dwarf::AttributeVersion(Attribute))
+      return;
+
     Die.addValue(DIEValueAllocator,
                  DIEValue(Attribute, Form, std::forward<T>(Value)));
   }

diff  --git a/llvm/test/DebugInfo/PowerPC/strict-dwarf.ll b/llvm/test/DebugInfo/PowerPC/strict-dwarf.ll
index b64fd426e8eab..27fbfdbcedf42 100644
--- a/llvm/test/DebugInfo/PowerPC/strict-dwarf.ll
+++ b/llvm/test/DebugInfo/PowerPC/strict-dwarf.ll
@@ -2,16 +2,25 @@
 ; RUN:   llvm-dwarfdump -debug-info - | FileCheck %s
 ; RUN: llc -filetype=obj -mtriple=powerpc64le-unknown-linux-gnu \
 ; RUN:   -strict-dwarf=true < %s | llvm-dwarfdump -debug-info - | \
-; RUN:   FileCheck %s
+; RUN:   FileCheck %s -check-prefix=STRICT
 
-; FIXME: when -strict-dwarf=true is specified, we should check "STRICT" to tell
-; that with DWARF 4, we should not generate DWARF 5 attribute DW_AT_noreturn and
-; DW_AT_alignment.
+; We also check that with/without -strict-dwarf=true, the location attribute
+; is not changed. The location attribute adding will call DwarfUnit::addUInt()
+; which contains a attribute 0, we want to make sure the strict-dwarf handling
+; is also right for attribute 0.
+; For this case, the location attribute adding is for global variable @_ZL3var
+; and the call chain to addUInt() is:
+; 1: DwarfCompileUnit::addLocationAttribute()
+; 2: DwarfUnit::addOpAddress()
+; 3: DwarfUnit::addUInt()
+; 4: addUInt(Block, (dwarf::Attribute)0, Form, Integer);
 
 ; CHECK: DW_AT_alignment
+; CHECK: DW_AT_location  (DW_OP_addr 0x0)
 ; CHECK: DW_AT_noreturn
 ; STRICT-NOT: DW_AT_noreturn
 ; STRICT-NOT: DW_AT_alignment
+; STRICT: DW_AT_location  (DW_OP_addr 0x0)
 
 @_ZL3var = internal global i32 0, align 16, !dbg !0