Rollup merge of #77950 - arlosi:sha256, r=eddyb

Add support for SHA256 source file hashing

Adds support for `-Z src-hash-algorithm sha256`, which became available in LLVM 11.

Using an older version of LLVM will cause an error `invalid checksum kind` if the hash algorithm is set to sha256.

r? `@eddyb`
cc #70401 `@est31`

6 files changed, 19 insertions, 4 deletions

diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 73c1f73ec7f..ef1ae807453 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -801,6 +801,7 @@ fn file_metadata_raw(
                     let kind = match hash.kind {
                         rustc_span::SourceFileHashAlgorithm::Md5 => llvm::ChecksumKind::MD5,
                         rustc_span::SourceFileHashAlgorithm::Sha1 => llvm::ChecksumKind::SHA1,
+                        rustc_span::SourceFileHashAlgorithm::Sha256 => llvm::ChecksumKind::SHA256,
                     };
                     (kind, hex_encode(hash.hash_bytes()))
                 }
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index daceda20097..8b15c8b0eb6 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -558,6 +558,7 @@ pub enum ChecksumKind {
     None,
     MD5,
     SHA1,
+    SHA256,
 }
 
 extern "C" {
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index 40a10434248..938eb19faef 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -648,6 +648,7 @@ enum class LLVMRustChecksumKind {
   None,
   MD5,
   SHA1,
+  SHA256,
 };
 
 static Optional<DIFile::ChecksumKind> fromRust(LLVMRustChecksumKind Kind) {
@@ -658,6 +659,10 @@ static Optional<DIFile::ChecksumKind> fromRust(LLVMRustChecksumKind Kind) {
     return DIFile::ChecksumKind::CSK_MD5;
   case LLVMRustChecksumKind::SHA1:
     return DIFile::ChecksumKind::CSK_SHA1;
+#if (LLVM_VERSION_MAJOR >= 11)
+  case LLVMRustChecksumKind::SHA256:
+    return DIFile::ChecksumKind::CSK_SHA256;
+#endif
   default:
     report_fatal_error("bad ChecksumKind.");
   }
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index 492457dde83..4c00361dd31 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -1076,7 +1076,7 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
     span_free_formats: bool = (false, parse_bool, [UNTRACKED],
         "exclude spans when debug-printing compiler state (default: no)"),
     src_hash_algorithm: Option<SourceFileHashAlgorithm> = (None, parse_src_file_hash, [TRACKED],
-        "hash algorithm of source files in debug info (`md5`, or `sha1`)"),
+        "hash algorithm of source files in debug info (`md5`, `sha1`, or `sha256`)"),
     strip: Strip = (Strip::None, parse_strip, [UNTRACKED],
         "tell the linker which information to strip (`none` (default), `debuginfo` or `symbols`)"),
     symbol_mangling_version: SymbolManglingVersion = (SymbolManglingVersion::Legacy,
diff --git a/compiler/rustc_span/Cargo.toml b/compiler/rustc_span/Cargo.toml
index 1abfd50f003..08645990c48 100644
--- a/compiler/rustc_span/Cargo.toml
+++ b/compiler/rustc_span/Cargo.toml
@@ -17,5 +17,6 @@ scoped-tls = "1.0"
 unicode-width = "0.1.4"
 cfg-if = "0.1.2"
 tracing = "0.1"
-sha-1 = "0.8"
-md-5 = "0.8"
+sha-1 = "0.9"
+sha2 = "0.9"
+md-5 = "0.9"
diff --git a/compiler/rustc_span/src/lib.rs b/compiler/rustc_span/src/lib.rs
index 0e3027273ab..97b5c11b0fe 100644
--- a/compiler/rustc_span/src/lib.rs
+++ b/compiler/rustc_span/src/lib.rs
@@ -59,6 +59,7 @@ use std::str::FromStr;
 use md5::Md5;
 use sha1::Digest;
 use sha1::Sha1;
+use sha2::Sha256;
 
 use tracing::debug;
 
@@ -1034,6 +1035,7 @@ pub struct OffsetOverflowError;
 pub enum SourceFileHashAlgorithm {
     Md5,
     Sha1,
+    Sha256,
 }
 
 impl FromStr for SourceFileHashAlgorithm {
@@ -1043,6 +1045,7 @@ impl FromStr for SourceFileHashAlgorithm {
         match s {
             "md5" => Ok(SourceFileHashAlgorithm::Md5),
             "sha1" => Ok(SourceFileHashAlgorithm::Sha1),
+            "sha256" => Ok(SourceFileHashAlgorithm::Sha256),
             _ => Err(()),
         }
     }
@@ -1055,7 +1058,7 @@ rustc_data_structures::impl_stable_hash_via_hash!(SourceFileHashAlgorithm);
 #[derive(HashStable_Generic, Encodable, Decodable)]
 pub struct SourceFileHash {
     pub kind: SourceFileHashAlgorithm,
-    value: [u8; 20],
+    value: [u8; 32],
 }
 
 impl SourceFileHash {
@@ -1071,6 +1074,9 @@ impl SourceFileHash {
             SourceFileHashAlgorithm::Sha1 => {
                 value.copy_from_slice(&Sha1::digest(data));
             }
+            SourceFileHashAlgorithm::Sha256 => {
+                value.copy_from_slice(&Sha256::digest(data));
+            }
         }
         hash
     }
@@ -1090,6 +1096,7 @@ impl SourceFileHash {
         match self.kind {
             SourceFileHashAlgorithm::Md5 => 16,
             SourceFileHashAlgorithm::Sha1 => 20,
+            SourceFileHashAlgorithm::Sha256 => 32,
         }
     }
 }