[Mips] Support R_MICROMIPS_SUB relocation handling

llvm-svn: 240265

lld/lib/ReaderWriter/ELF/Mips/MipsRelocationHandler.cpp

@@ -74,6 +74,8 @@ static MipsRelocationParams getRelocationParams(uint32_t rType) {
   case R_MIPS_64:
   case R_MIPS_SUB:
     return {8, 0xffffffffffffffffull, 0, false, dummyCheck};
+  case R_MICROMIPS_SUB:
+    return {8, 0xffffffffffffffffull, 0, true, dummyCheck};
   case R_MIPS_32:
   case R_MIPS_GPREL32:
   case R_MIPS_REL32:
@@ -350,8 +352,9 @@ static CrossJumpMode getCrossJumpMode(const Reference &ref) {
   }
 }
 
-static uint32_t microShuffle(uint32_t ins) {
-  return ((ins & 0xffff) << 16) | ((ins & 0xffff0000) >> 16);
+static uint64_t microShuffle(uint64_t ins) {
+  return (ins & 0xffffffff00000000ull) | ((ins & 0xffff) << 16) |
+         ((ins & 0xffff0000) >> 16);
 }
 
 static ErrorOr<int64_t> calculateRelocation(Reference::KindValue kind,
@@ -368,6 +371,7 @@ static ErrorOr<int64_t> calculateRelocation(Reference::KindValue kind,
   case R_MIPS_64:
     return tgtAddr + addend;
   case R_MIPS_SUB:
+  case R_MICROMIPS_SUB:
     return tgtAddr - addend;
   case R_MIPS_26:
     return reloc26loc(relAddr, tgtAddr, addend, 2);

lld/test/elf/Mips/rel-sub-micro.test

@@ -0,0 +1,62 @@
+# Check handling of R_MICROMIPS_SUB relocation.
+
+# RUN: yaml2obj -format=elf %s > %t.o
+# RUN: lld -flavor gnu -target mips64el -o %t.exe %t.o
+# RUN: llvm-objdump -s -t %t.exe | FileCheck %s
+
+# CHECK: Contents of section .data:
+# CHECK-NEXT: 120002000 0020cc01 01000000 0020d001 0100ffff
+#                       ^^ __start - 4 = 0x1200001cc
+#                                         ^^ __start - 0x1000000000000
+#                                              = 0xffff0001200001d0
+# CHECK: SYMBOL TABLE:
+# CHECK: 00000001200001d0 g .rodata 00000008 __start
+
+FileHeader:
+  Class:    ELFCLASS64
+  Data:     ELFDATA2LSB
+  Type:     ET_REL
+  Machine:  EM_MIPS
+  Flags:    [EF_MIPS_PIC, EF_MIPS_CPIC, EF_MIPS_ARCH_64, EF_MIPS_MICROMIPS]
+
+Sections:
+- Name:          .text
+  Type:          SHT_PROGBITS
+  Size:          8
+  AddressAlign:  16
+  Flags:         [SHF_ALLOC]
+
+- Name:          .data
+  Type:          SHT_PROGBITS
+  Size:          16
+  AddressAlign:  16
+  Flags:         [SHF_ALLOC, SHF_WRITE]
+
+- Name:          .rela.data
+  Type:          SHT_RELA
+  Info:          .data
+  AddressAlign:  4
+  Relocations:
+    - Offset:  0
+      Symbol:  __start
+      Type:    R_MICROMIPS_SUB
+      Addend:  4
+    - Offset:  8
+      Symbol:  __start
+      Type:    R_MICROMIPS_SUB
+      Addend:  0x1000000000000
+
+Symbols:
+  Global:
+    - Name:     __start
+      Section:  .text
+      Value:    0
+      Size:     8
+    - Name:     D1
+      Section:  .data
+      Value:    0
+      Size:     8
+    - Name:     D2
+      Section:  .data
+      Value:    8
+      Size:     8