Index: ELF/InputSection.cpp
===================================================================
--- ELF/InputSection.cpp
+++ ELF/InputSection.cpp
@@ -862,6 +862,16 @@
   return cast_or_null<SyntheticSection>(Parent);
 }
 
+// Helper is used for hashing short data, like mergeable strings.
+static uint64_t hashString(const char *Data, size_t Size) {
+  // Optimize for 1 byte strings case. For example, scylla has
+  // about 15k of one byte zeroes.
+  if (Size == 1)
+    return *Data;
+  // Use fixed seed value.
+  return hashing::detail::hash_short(Data, Size, 0xff51afd7ed558ccdULL);
+}
+
 // Split SHF_STRINGS section. Such section is a sequence of
 // null-terminated strings.
 void MergeInputSection::splitStrings(ArrayRef<uint8_t> Data, size_t EntSize) {
@@ -875,7 +885,7 @@
       fatal(toString(this) + ": string is not null terminated");
     size_t Size = End + EntSize;
 
-    Pieces.emplace_back(Off, xxHash64(S.substr(0, Size)), !IsAlloc);
+    Pieces.emplace_back(Off, hashString(S.data(), Size), !IsAlloc);
     S = S.substr(Size);
     Off += Size;
   }
Index: test/ELF/comment-gc.s
===================================================================
--- test/ELF/comment-gc.s
+++ test/ELF/comment-gc.s
@@ -5,7 +5,7 @@
 # RUN: llvm-objdump -s %t1 | FileCheck %s
 
 # CHECK:      Contents of section .comment:
-# CHECK-NEXT: foo..LLD 1.0.bar
+# CHECK-NEXT: .foo.LLD 1.0.bar
 
 .ident "foo"
 
Index: test/ELF/debug-gc.s
===================================================================
--- test/ELF/debug-gc.s
+++ test/ELF/debug-gc.s
@@ -4,11 +4,11 @@
 # RUN: llvm-objdump -s %t1 | FileCheck %s
 
 # CHECK:      Contents of section .debug_str:
-# CHECK-NEXT:  0000 41414100 43434300 42424200           AAA.CCC.BBB.
+# CHECK-NEXT:  0000 41414100 42424200 43434300           AAA.BBB.CCC.
 # CHECK:      Contents of section .foo:
 # CHECK-NEXT:  0000 2a000000
 # CHECK:      Contents of section .debug_info:
-# CHECK-NEXT:  0000 00000000 08000000
+# CHECK-NEXT:  0000 00000000 04000000
 
 .globl _start
 _start:
Index: test/ELF/emit-relocs-mergeable-i386.s
===================================================================
--- test/ELF/emit-relocs-mergeable-i386.s
+++ test/ELF/emit-relocs-mergeable-i386.s
@@ -5,7 +5,7 @@
 
 ## Check lf we produce proper relocations when doing merging of SHF_MERGE sections.
 
-## Check addends of relocations are: 0x0, 0x8, 0x8, 0x4
+## Check addends of relocations are: 0x0, 0x4, 0x4, 0x8
 # CHECK:      Section {
 # CHECK:        Index:
 # CHECK:        Name: .foo
@@ -22,11 +22,11 @@
 # CHECK-NEXT:   AddressAlignment:
 # CHECK-NEXT:   EntrySize:
 # CHECK-NEXT:   SectionData (
-# CHECK-NEXT:     0000: 00000000 08000000 08000000 04000000
+# CHECK-NEXT:     0000: 00000000 04000000 04000000 08000000
 # CHECK-NEXT:   )
 # CHECK-NEXT: }
 
-## Check that offsets for AAA is 0x0, for BBB is 0x8 and CCC has offset 0x4.
+## Check that offsets for AAA is 0x0, for BBB is 0x4 and CCC has offset 0x8.
 # CHECK:      Section {
 # CHECK:        Index:
 # CHECK:        Name: .strings
@@ -43,7 +43,7 @@
 # CHECK-NEXT:   AddressAlignment:
 # CHECK-NEXT:   EntrySize:
 # CHECK-NEXT:   SectionData (
-# CHECK-NEXT:     |AAA.CCC.BBB.|
+# CHECK-NEXT:     |AAA.BBB.CCC.|
 # CHECK-NEXT:   )
 # CHECK-NEXT: }
 
Index: test/ELF/emit-relocs-mergeable.s
===================================================================
--- test/ELF/emit-relocs-mergeable.s
+++ test/ELF/emit-relocs-mergeable.s
@@ -21,16 +21,16 @@
 # CHECK-NEXT:   AddressAlignment:
 # CHECK-NEXT:   EntrySize:
 # CHECK-NEXT:   SectionData (
-# CHECK-NEXT:     0000: 41414100 43434300 42424200 |AAA.CCC.BBB.|
+# CHECK-NEXT:     0000: 41414100 42424200 43434300 |AAA.BBB.CCC.|
 # CHECK-NEXT:   )
 # CHECK-NEXT: }
 
 # CHECK:      Relocations [
 # CHECK-NEXT:   Section {{.*}} .rela.foo {
 # CHECK-NEXT:     0x201000 R_X86_64_64 .strings 0x0
-# CHECK-NEXT:     0x201008 R_X86_64_64 .strings 0x8
-# CHECK-NEXT:     0x201010 R_X86_64_64 .strings 0x8
-# CHECK-NEXT:     0x201018 R_X86_64_64 .strings 0x4
+# CHECK-NEXT:     0x201008 R_X86_64_64 .strings 0x4
+# CHECK-NEXT:     0x201010 R_X86_64_64 .strings 0x4
+# CHECK-NEXT:     0x201018 R_X86_64_64 .strings 0x8
 # CHECK-NEXT:   }
 # CHECK-NEXT: ]