Add a hashing routine that handles hashing types. Add a test for
hashing the contents of DW_FORM_data1 on top of a type with attributes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189862 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/DIEHash.cpp b/lib/CodeGen/AsmPrinter/DIEHash.cpp
index 1581c96..519c8a0 100644
--- a/lib/CodeGen/AsmPrinter/DIEHash.cpp
+++ b/lib/CodeGen/AsmPrinter/DIEHash.cpp
@@ -422,6 +422,7 @@
/// This is based on the type signature computation given in section 7.27 of the
/// DWARF4 standard. It is an md5 hash of the flattened description of the DIE
/// with the inclusion of the full CU and all top level CU entities.
+// TODO: Initialize the type chain at 0 instead of 1 for CU signatures.
uint64_t DIEHash::computeCUSignature(DIE *Die) {
// Hash the DIE.
@@ -436,3 +437,22 @@
// appropriately.
return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
}
+
+/// This is based on the type signature computation given in section 7.27 of the
+/// DWARF4 standard. It is an md5 hash of the flattened description of the DIE
+/// with the inclusion of additional forms not specifically called out in the
+/// standard.
+uint64_t DIEHash::computeTypeSignature(DIE *Die) {
+
+ // Hash the DIE.
+ computeHash(Die);
+
+ // Now return the result.
+ MD5::MD5Result Result;
+ Hash.final(Result);
+
+ // ... take the least significant 8 bytes and return those. Our MD5
+ // implementation always returns its results in little endian, swap bytes
+ // appropriately.
+ return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
+}
diff --git a/lib/CodeGen/AsmPrinter/DIEHash.h b/lib/CodeGen/AsmPrinter/DIEHash.h
index f98b56d..b792aea 100644
--- a/lib/CodeGen/AsmPrinter/DIEHash.h
+++ b/lib/CodeGen/AsmPrinter/DIEHash.h
@@ -87,6 +87,9 @@
/// \brief Computes the CU signature.
uint64_t computeCUSignature(DIE *Die);
+ /// \brief Computes the type signature.
+ uint64_t computeTypeSignature(DIE *Die);
+
// Helper routines to process parts of a DIE.
private:
/// \brief Adds the parent context of \param Die to the hash.