[mips] Emit R_MICROMIPS_HIGHER / R_MICROMIPS_HIGHEST relocations

[atanasyan]

Summary

Emit R_MICROMIPS_HIGHER / R_MICROMIPS_HIGHEST relocations for %higher() and %highest() expressions in case of microMIPS. These relocations do exactly the same things as R_MIPS_HIGHER / R_MIPS_HIGHEST, but for consistency it's better to write microMIPS variants.

[smaksimovic]

LGTM

[atanasyan]

Thanks for review.

lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp

static unsigned adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
   case Mips::fixup_Mips_GOT_HI16:
   case Mips::fixup_Mips_CALL_HI16:
   case Mips::fixup_MICROMIPS_HI16:
   case Mips::fixup_MIPS_PCHI16:
     // Get the 2nd 16-bits. Also add 1 if bit 15 is 1.
     Value = ((Value + 0x8000) >> 16) & 0xffff;
     break;
   case Mips::fixup_Mips_HIGHER:
+  case Mips::fixup_MICROMIPS_HIGHER:
     // Get the 3rd 16-bits.
     Value = ((Value + 0x80008000LL) >> 32) & 0xffff;
     break;
   case Mips::fixup_Mips_HIGHEST:
+  case Mips::fixup_MICROMIPS_HIGHEST:
     // Get the 4th 16-bits.
     Value = ((Value + 0x800080008000LL) >> 48) & 0xffff;
     break;
   case Mips::fixup_MICROMIPS_26_S1:
     Value >>= 1;
     break;
   case Mips::fixup_MICROMIPS_PC7_S1:
     Value -= 4;
const static MCFixupKindInfo LittleEndianInfos[] = {
     { "fixup_Mips_DTPREL_LO",    0,     16,   0 },
     { "fixup_Mips_Branch_PCRel", 0,     16,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_Mips_GPOFF_HI",     0,     16,   0 },
     { "fixup_Mips_GPOFF_LO",     0,     16,   0 },
     { "fixup_Mips_GOT_PAGE",     0,     16,   0 },
     { "fixup_Mips_GOT_OFST",     0,     16,   0 },
     { "fixup_Mips_GOT_DISP",     0,     16,   0 },
     { "fixup_Mips_HIGHER",       0,     16,   0 },
+    { "fixup_MICROMIPS_HIGHER",  0,     16,   0 },
     { "fixup_Mips_HIGHEST",      0,     16,   0 },
+    { "fixup_MICROMIPS_HIGHEST", 0,     16,   0 },
     { "fixup_Mips_GOT_HI16",     0,     16,   0 },
     { "fixup_Mips_GOT_LO16",     0,     16,   0 },
     { "fixup_Mips_CALL_HI16",    0,     16,   0 },
     { "fixup_Mips_CALL_LO16",    0,     16,   0 },
     { "fixup_Mips_PC18_S3",      0,     18,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_MIPS_PC19_S2",      0,     19,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_MIPS_PC21_S2",      0,     21,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_MIPS_PC26_S2",      0,     26,  MCFixupKindInfo::FKF_IsPCRel },
const static MCFixupKindInfo BigEndianInfos[] = {
     { "fixup_Mips_DTPREL_LO",   16,     16,   0 },
     { "fixup_Mips_Branch_PCRel",16,     16,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_Mips_GPOFF_HI",    16,     16,   0 },
     { "fixup_Mips_GPOFF_LO",    16,     16,   0 },
     { "fixup_Mips_GOT_PAGE",    16,     16,   0 },
     { "fixup_Mips_GOT_OFST",    16,     16,   0 },
     { "fixup_Mips_GOT_DISP",    16,     16,   0 },
     { "fixup_Mips_HIGHER",      16,     16,   0 },
+    { "fixup_MICROMIPS_HIGHER", 16,     16,   0 },
     { "fixup_Mips_HIGHEST",     16,     16,   0 },
+    { "fixup_MICROMIPS_HIGHEST",16,     16,   0 },
     { "fixup_Mips_GOT_HI16",    16,     16,   0 },
     { "fixup_Mips_GOT_LO16",    16,     16,   0 },
     { "fixup_Mips_CALL_HI16",   16,     16,   0 },
     { "fixup_Mips_CALL_LO16",   16,     16,   0 },
     { "fixup_Mips_PC18_S3",     14,     18,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_MIPS_PC19_S2",     13,     19,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_MIPS_PC21_S2",     11,     21,  MCFixupKindInfo::FKF_IsPCRel },
     { "fixup_MIPS_PC26_S2",      6,     26,  MCFixupKindInfo::FKF_IsPCRel },

lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp

unsigned MipsELFObjectWriter::getRelocType(MCContext &Ctx,
   case Mips::fixup_MICROMIPS_GOTTPREL:
     return ELF::R_MICROMIPS_TLS_GOTTPREL;
   case Mips::fixup_MICROMIPS_TLS_TPREL_HI16:
     return ELF::R_MICROMIPS_TLS_TPREL_HI16;
   case Mips::fixup_MICROMIPS_TLS_TPREL_LO16:
     return ELF::R_MICROMIPS_TLS_TPREL_LO16;
   case Mips::fixup_MICROMIPS_SUB:
     return ELF::R_MICROMIPS_SUB;
+  case Mips::fixup_MICROMIPS_HIGHER:
+    return ELF::R_MICROMIPS_HIGHER;
+  case Mips::fixup_MICROMIPS_HIGHEST:
+    return ELF::R_MICROMIPS_HIGHEST;
   }
 
   llvm_unreachable("invalid fixup kind!");
 }
 
 /// Sort relocation table entries by offset except where another order is
 /// required by the MIPS ABI.
 ///

lib/Target/Mips/MCTargetDesc/MipsFixupKinds.h

enum Fixups {
     fixup_Mips_GOT_PAGE,
 
     // resulting in - R_MIPS_GOT_OFST
     fixup_Mips_GOT_OFST,
 
     // resulting in - R_MIPS_GOT_DISP
     fixup_Mips_GOT_DISP,
 
-    // resulting in - R_MIPS_GOT_HIGHER
+    // resulting in - R_MIPS_HIGHER/R_MICROMIPS_HIGHER 
     fixup_Mips_HIGHER,
+    fixup_MICROMIPS_HIGHER,
 
-    // resulting in - R_MIPS_HIGHEST
+    // resulting in - R_MIPS_HIGHEST/R_MICROMIPS_HIGHEST
     fixup_Mips_HIGHEST,
+    fixup_MICROMIPS_HIGHEST,
 
     // resulting in - R_MIPS_GOT_HI16
     fixup_Mips_GOT_HI16,
 
     // resulting in - R_MIPS_GOT_LO16
     fixup_Mips_GOT_LO16,
 
     // resulting in - R_MIPS_CALL_HI16

lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp

case MipsMCExpr::MEK_LO:
       if (MipsExpr->isGpOff()) {
         FixupKind = Mips::fixup_Mips_GPOFF_LO;
         break;
       }
       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_LO16
                                    : Mips::fixup_Mips_LO16;
       break;
     case MipsMCExpr::MEK_HIGHEST:
-      FixupKind = Mips::fixup_Mips_HIGHEST;
+      FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_HIGHEST
+                                   : Mips::fixup_Mips_HIGHEST;
       break;
     case MipsMCExpr::MEK_HIGHER:
-      FixupKind = Mips::fixup_Mips_HIGHER;
+      FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_HIGHER
+                                   : Mips::fixup_Mips_HIGHER;
       break;
     case MipsMCExpr::MEK_HI:
       // Check for %hi(%neg(%gp_rel(X)))
       if (MipsExpr->isGpOff()) {
         FixupKind = Mips::fixup_Mips_GPOFF_HI;
         break;
       }
       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_HI16

test/MC/Mips/relocation.s

foo_mm:
                                            // ENCLE: addiu $2, $3, %got(bar) # encoding: [0x43'A',0x30'A',0x00,0x00]
                                            // FIXUP: # fixup A - offset: 0, value: %got(bar), kind: fixup_MICROMIPS_GOT16
         // %got requires a %lo pair
         addiu $2, $2, %lo(bar)             // RELOC: R_MICROMIPS_LO16 .data
                                            // ENCBE: addiu $2, $2, %lo(bar) # encoding: [0x30,0x42,A,A]
                                            // ENCLE: addiu $2, $2, %lo(bar) # encoding: [0x42'A',0x30'A',0x00,0x00]
                                            // FIXUP: # fixup A - offset: 0, value: %lo(bar), kind: fixup_MICROMIPS_LO16
 
-// DATA-NEXT:  0010: 30430000 30420004 30430001 30420034
+// DATA-NEXT:  0010: 30430000 30420004 30430001 3042003C
         addiu $2, $3, %got(baz)            // RELOC: R_MICROMIPS_GOT16 .text
                                            // ENCBE: addiu $2, $3, %got(baz) # encoding: [0x30,0x43,A,A]
                                            // The placement of the 'A' annotations is incorrect. They use 32-bit little endian instead of 2x 16-bit little endian.
                                            // ENCLE: addiu $2, $3, %got(baz) # encoding: [0x43'A',0x30'A',0x00,0x00]
                                            // FIXUP: # fixup A - offset: 0, value: %got(baz), kind: fixup_MICROMIPS_GOT16
         // %got requires a %lo pair
         addiu $2, $2, %lo(baz)             // RELOC: R_MICROMIPS_LO16 .text
                                            // ENCBE: addiu $2, $2, %lo(baz) # encoding: [0x30,0x42,A,A]
// DATA-NEXT:  0030: 30430000 30420000 30430000 30420004
                                            // ENCLE: addiu $2, $3, %hi(bar) # encoding: [0x43'A',0x30'A',0x00,0x00]
                                            // FIXUP: # fixup A - offset: 0, value: %hi(bar), kind: fixup_MICROMIPS_HI16
 
         addiu $2, $2, %lo(bar)             // RELOC: R_MICROMIPS_LO16 .data
                                            // ENCBE: addiu $2, $2, %lo(bar) # encoding: [0x30,0x42,A,A]
                                            // ENCLE: addiu $2, $2, %lo(bar) # encoding: [0x42'A',0x30'A',0x00,0x00]
                                            // FIXUP: # fixup A - offset: 0, value: %lo(bar), kind: fixup_MICROMIPS_LO16
 
-// DATA-NEXT:  0040: 30430000 00000000 00000000 00000000
+// DATA-NEXT:  0040: 30430000 41A50000 41A50000 00000000
         addiu $2, $3, %gottprel(foo)       // RELOC: R_MICROMIPS_TLS_GOTTPREL foo
                                            // ENCBE: addiu $2, $3, %gottprel(foo) # encoding: [0x30,0x43,A,A]
                                            // ENCLE: addiu $2, $3, %gottprel(foo) # encoding: [0x43'A',0x30'A',0x00,0x00]
                                            // FIXUP: # fixup A - offset: 0, value: %gottprel(foo), kind: fixup_MICROMIPS_GOTTPREL
 
+        lui $5, %higher(foo)               // RELOC: R_MICROMIPS_HIGHER foo
+                                           // ENCBE: lui $5, %higher(foo) # encoding: [0x41,0xa5,A,A]
+                                           // ENCLE: lui $5, %higher(foo) # encoding: [0xa5'A',0x41'A',0x00,0x00]
+                                           // FIXUP: # fixup A - offset: 0, value: %higher(foo), kind: fixup_MICROMIPS_HIGHER
+
+        lui $5, %highest(foo)              // RELOC: R_MICROMIPS_HIGHEST foo
+                                           // ENCBE: lui $5, %highest(foo) # encoding: [0x41,0xa5,A,A]
+                                           // ENCLE: lui $5, %highest(foo) # encoding: [0xa5'A',0x41'A',0x00,0x00]
+                                           // FIXUP: # fixup A - offset: 0, value: %highest(foo), kind: fixup_MICROMIPS_HIGHEST
+
         .space 65520, 0
 long_mm: