[llvm] 1478ed6 - Add support for SHA256 source file checksums in debug info

[Reid Kleckner via llvm-commits]

Author: Arlo Siemsen
Date: 2020-03-12T16:32:05-07:00
New Revision: 1478ed69d3dfc177a77e799af13075dd4474bcd0

URL: https://github.com/llvm/llvm-project/commit/1478ed69d3dfc177a77e799af13075dd4474bcd0
DIFF: https://github.com/llvm/llvm-project/commit/1478ed69d3dfc177a77e799af13075dd4474bcd0.diff

LOG: Add support for SHA256 source file checksums in debug info

LLVM currently supports CSK_MD5 and CSK_SHA1 source file checksums in
debug info. This change adds support for CSK_SHA256 checksums.

The SHA256 checksums are supported by the CodeView debug format.

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D75785

Added: 
    llvm/test/Assembler/dbg-checksum.ll

Modified: 
    llvm/docs/LangRef.rst
    llvm/include/llvm/IR/DebugInfoMetadata.h
    llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
    llvm/lib/IR/DebugInfoMetadata.cpp
    llvm/lib/IR/Verifier.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index 4db8aa1bc939..3d1f9d388319 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -4568,7 +4568,7 @@ DIFile
 
 Files are sometimes used in ``scope:`` fields, and are the only valid target
 for ``file:`` fields.
-Valid values for ``checksumkind:`` field are: {CSK_None, CSK_MD5, CSK_SHA1}
+Valid values for ``checksumkind:`` field are: {CSK_None, CSK_MD5, CSK_SHA1, CSK_SHA256}
 
 .. _DIBasicType:
 

diff  --git a/llvm/include/llvm/IR/DebugInfoMetadata.h b/llvm/include/llvm/IR/DebugInfoMetadata.h
index 221ff519e2f5..6056337fdff1 100644
--- a/llvm/include/llvm/IR/DebugInfoMetadata.h
+++ b/llvm/include/llvm/IR/DebugInfoMetadata.h
@@ -465,7 +465,8 @@ class DIFile : public DIScope {
     // encoding is reserved.
     CSK_MD5 = 1,
     CSK_SHA1 = 2,
-    CSK_Last = CSK_SHA1 // Should be last enumeration.
+    CSK_SHA256 = 3,
+    CSK_Last = CSK_SHA256 // Should be last enumeration.
   };
 
   /// A single checksum, represented by a \a Kind and a \a Value (a string).

diff  --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index 6dc6fde9a292..814273c6a39f 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -250,8 +250,15 @@ unsigned CodeViewDebug::maybeRecordFile(const DIFile *F) {
       ChecksumAsBytes = ArrayRef<uint8_t>(
           reinterpret_cast<const uint8_t *>(CKMem), Checksum.size());
       switch (F->getChecksum()->Kind) {
-      case DIFile::CSK_MD5:  CSKind = FileChecksumKind::MD5; break;
-      case DIFile::CSK_SHA1: CSKind = FileChecksumKind::SHA1; break;
+      case DIFile::CSK_MD5:
+        CSKind = FileChecksumKind::MD5;
+        break;
+      case DIFile::CSK_SHA1:
+        CSKind = FileChecksumKind::SHA1;
+        break;
+      case DIFile::CSK_SHA256:
+        CSKind = FileChecksumKind::SHA256;
+        break;
       }
     }
     bool Success = OS.EmitCVFileDirective(NextId, FullPath, ChecksumAsBytes,

diff  --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index 0c0ea50dde70..289d4159683b 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -479,8 +479,9 @@ DISubroutineType *DISubroutineType::getImpl(LLVMContext &Context, DIFlags Flags,
 // FIXME: Implement this string-enum correspondence with a .def file and macros,
 // so that the association is explicit rather than implied.
 static const char *ChecksumKindName[DIFile::CSK_Last] = {
-  "CSK_MD5",
-  "CSK_SHA1"
+    "CSK_MD5",
+    "CSK_SHA1",
+    "CSK_SHA256",
 };
 
 StringRef DIFile::getChecksumKindAsString(ChecksumKind CSKind) {
@@ -495,6 +496,7 @@ Optional<DIFile::ChecksumKind> DIFile::getChecksumKind(StringRef CSKindStr) {
   return StringSwitch<Optional<DIFile::ChecksumKind>>(CSKindStr)
       .Case("CSK_MD5", DIFile::CSK_MD5)
       .Case("CSK_SHA1", DIFile::CSK_SHA1)
+      .Case("CSK_SHA256", DIFile::CSK_SHA256)
       .Default(None);
 }
 

diff  --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 676f98dae0bb..1053304995c9 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -1034,6 +1034,9 @@ void Verifier::visitDIFile(const DIFile &N) {
     case DIFile::CSK_SHA1:
       Size = 40;
       break;
+    case DIFile::CSK_SHA256:
+      Size = 64;
+      break;
     }
     AssertDI(Checksum->Value.size() == Size, "invalid checksum length", &N);
     AssertDI(Checksum->Value.find_if_not(llvm::isHexDigit) == StringRef::npos,

diff  --git a/llvm/test/Assembler/dbg-checksum.ll b/llvm/test/Assembler/dbg-checksum.ll
new file mode 100644
index 000000000000..47af2adbf8cb
--- /dev/null
+++ b/llvm/test/Assembler/dbg-checksum.ll
@@ -0,0 +1,20 @@
+; Test that DIFile(checksumkind, checksum) can round-trip through bitcode.
+;
+; RUN: llvm-as < %s | llvm-dis | llvm-as | llvm-dis | FileCheck %s
+
+!llvm.dbg.cu = !{!1, !2, !3, !4}
+!llvm.module.flags = !{!9}
+
+!1 = distinct !DICompileUnit(language: DW_LANG_C99, file: !5, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
+!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !6, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
+!3 = distinct !DICompileUnit(language: DW_LANG_C99, file: !7, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
+!4 = distinct !DICompileUnit(language: DW_LANG_C99, file: !8, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
+; CHECK: !DIFile(filename: "a.h", directory: "/test")
+!5 = !DIFile(filename: "a.h", directory: "/test")
+; CHECK: !DIFile(filename: "b.h", directory: "/test", checksumkind: CSK_MD5, checksum: "595f44fec1e92a71d3e9e77456ba80d1")
+!6 = !DIFile(filename: "b.h", directory: "/test", checksumkind: CSK_MD5, checksum: "595f44fec1e92a71d3e9e77456ba80d1")
+; CHECK: !DIFile(filename: "c.h", directory: "/test", checksumkind: CSK_SHA1, checksum: "d5db29cd03a2ed055086cef9c31c252b4587d6d0")
+!7 = !DIFile(filename: "c.h", directory: "/test", checksumkind: CSK_SHA1, checksum: "d5db29cd03a2ed055086cef9c31c252b4587d6d0")
+; CHECK: !DIFile(filename: "d.h", directory: "/test", checksumkind: CSK_SHA256, checksum: "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855")
+!8 = !DIFile(filename: "d.h", directory: "/test", checksumkind: CSK_SHA256, checksum: "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855")
+!9 = !{i32 2, !"Debug Info Version", i32 3}