From 7cbb839d2be6af289da4bbbd7e81c4025b1ace72 Mon Sep 17 00:00:00 2001
From: Sagar Thakur <sagar.thakur@imgtec.com>
Date: Thu, 22 Jun 2017 12:48:04 +0000
Subject: [PATCH] Revert [mips] Adds support for R_MIPS_26, HIGHER, HIGHEST
 relocations in RuntimeDyld

Reverting due to build bot failures



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306000 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../RuntimeDyld/RuntimeDyld.cpp               | 38 ++------
 .../RuntimeDyld/RuntimeDyldELF.cpp            | 91 ++-----------------
 .../RuntimeDyld/RuntimeDyldELF.h              |  4 +-
 .../Targets/RuntimeDyldELFMips.cpp            |  6 --
 4 files changed, 15 insertions(+), 124 deletions(-)

diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
index d047697583a..2b69f1a0269 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -861,7 +861,7 @@ uint8_t *RuntimeDyldImpl::createStubFunction(uint8_t *Addr,
     // and stubs for branches Thumb - ARM and ARM - Thumb.
     writeBytesUnaligned(0xe51ff004, Addr, 4); // ldr pc,<label>
     return Addr + 4;
-  } else if (IsMipsO32ABI || IsMipsN32ABI) {
+  } else if (IsMipsO32ABI) {
     // 0:   3c190000        lui     t9,%hi(addr).
     // 4:   27390000        addiu   t9,t9,%lo(addr).
     // 8:   03200008        jr      t9.
@@ -869,39 +869,13 @@ uint8_t *RuntimeDyldImpl::createStubFunction(uint8_t *Addr,
     const unsigned LuiT9Instr = 0x3c190000, AdduiT9Instr = 0x27390000;
     const unsigned NopInstr = 0x0;
     unsigned JrT9Instr = 0x03200008;
-    if ((AbiVariant & ELF::EF_MIPS_ARCH) == ELF::EF_MIPS_ARCH_32R6 ||
-        (AbiVariant & ELF::EF_MIPS_ARCH) == ELF::EF_MIPS_ARCH_64R6)
-      JrT9Instr = 0x03200009;
+    if ((AbiVariant & ELF::EF_MIPS_ARCH) == ELF::EF_MIPS_ARCH_32R6)
+        JrT9Instr = 0x03200009;
 
     writeBytesUnaligned(LuiT9Instr, Addr, 4);
-    writeBytesUnaligned(AdduiT9Instr, Addr + 4, 4);
-    writeBytesUnaligned(JrT9Instr, Addr + 8, 4);
-    writeBytesUnaligned(NopInstr, Addr + 12, 4);
-    return Addr;
-  } else if (IsMipsN64ABI) {
-    // 0:   3c190000        lui     t9,%highest(addr).
-    // 4:   67390000        daddiu  t9,t9,%higher(addr).
-    // 8:   0019CC38        dsll    t9,t9,16.
-    // c:   67390000        daddiu  t9,t9,%hi(addr).
-    // 10:  0019CC38        dsll    t9,t9,16.
-    // 14:  67390000        daddiu  t9,t9,%lo(addr).
-    // 18:  03200008        jr      t9.
-    // 1c:  00000000        nop.
-    const unsigned LuiT9Instr = 0x3c190000, DaddiuT9Instr = 0x67390000,
-                   DsllT9Instr = 0x19CC38;
-    const unsigned NopInstr = 0x0;
-    unsigned JrT9Instr = 0x03200008;
-    if ((AbiVariant & ELF::EF_MIPS_ARCH) == ELF::EF_MIPS_ARCH_64R6)
-      JrT9Instr = 0x03200009;
-
-    writeBytesUnaligned(LuiT9Instr, Addr, 4);
-    writeBytesUnaligned(DaddiuT9Instr, Addr + 4, 4);
-    writeBytesUnaligned(DsllT9Instr, Addr + 8, 4);
-    writeBytesUnaligned(DaddiuT9Instr, Addr + 12, 4);
-    writeBytesUnaligned(DsllT9Instr, Addr + 16, 4);
-    writeBytesUnaligned(DaddiuT9Instr, Addr + 20, 4);
-    writeBytesUnaligned(JrT9Instr, Addr + 24, 4);
-    writeBytesUnaligned(NopInstr, Addr + 28, 4);
+    writeBytesUnaligned(AdduiT9Instr, Addr+4, 4);
+    writeBytesUnaligned(JrT9Instr, Addr+8, 4);
+    writeBytesUnaligned(NopInstr, Addr+12, 4);
     return Addr;
   } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
     // Depending on which version of the ELF ABI is in use, we need to
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
index 652e90922e4..3d12eadea4d 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
@@ -1251,7 +1251,8 @@ RuntimeDyldELF::processRelocationRef(
         if (Value.SymbolName) {
           addRelocationForSymbol(REHi, Value.SymbolName);
           addRelocationForSymbol(RELo, Value.SymbolName);
-        } else {
+        }
+        else {
           addRelocationForSection(REHi, Value.SectionID);
           addRelocationForSection(RELo, Value.SectionID);
         }
@@ -1300,14 +1301,10 @@ RuntimeDyldELF::processRelocationRef(
       processSimpleRelocation(SectionID, Offset, RelType, Value);
     }
   } else if (IsMipsN32ABI || IsMipsN64ABI) {
-    uint8_t *Placeholder = reinterpret_cast<uint8_t *>(
-        computePlaceholderAddress(SectionID, Offset));
-    uint32_t Opcode = readBytesUnaligned(Placeholder, 4);
-
     uint32_t r_type = RelType & 0xff;
     RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
-    if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE ||
-        r_type == ELF::R_MIPS_GOT_DISP) {
+    if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE
+        || r_type == ELF::R_MIPS_GOT_DISP) {
       StringMap<uint64_t>::iterator i = GOTSymbolOffsets.find(TargetName);
       if (i != GOTSymbolOffsets.end())
         RE.SymOffset = i->second;
@@ -1315,83 +1312,11 @@ RuntimeDyldELF::processRelocationRef(
         RE.SymOffset = allocateGOTEntries(1);
         GOTSymbolOffsets[TargetName] = RE.SymOffset;
       }
-      if (Value.SymbolName)
-        addRelocationForSymbol(RE, Value.SymbolName);
-      else
-        addRelocationForSection(RE, Value.SectionID);
-    } else if (RelType == ELF::R_MIPS_26) {
-      // This is an Mips branch relocation, need to use a stub function.
-      DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
-      SectionEntry &Section = Sections[SectionID];
-
-      //  Look up for existing stub.
-      StubMap::const_iterator i = Stubs.find(Value);
-      if (i != Stubs.end()) {
-        RelocationEntry RE(SectionID, Offset, RelType, i->second);
-        addRelocationForSection(RE, SectionID);
-        DEBUG(dbgs() << " Stub function found\n");
-      } else {
-        // Create a new stub function.
-        DEBUG(dbgs() << " Create a new stub function\n");
-        Stubs[Value] = Section.getStubOffset();
-
-        unsigned AbiVariant;
-        O.getPlatformFlags(AbiVariant);
-
-        uint8_t *StubTargetAddr = createStubFunction(
-            Section.getAddressWithOffset(Section.getStubOffset()), AbiVariant);
-
-        if (IsMipsN32ABI) {
-          // Creating Hi and Lo relocations for the filled stub instructions.
-          RelocationEntry REHi(SectionID, StubTargetAddr - Section.getAddress(),
-                               ELF::R_MIPS_HI16, Value.Addend);
-          RelocationEntry RELo(SectionID,
-                               StubTargetAddr - Section.getAddress() + 4,
-                               ELF::R_MIPS_LO16, Value.Addend);
-          if (Value.SymbolName) {
-            addRelocationForSymbol(REHi, Value.SymbolName);
-            addRelocationForSymbol(RELo, Value.SymbolName);
-          } else {
-            addRelocationForSection(REHi, Value.SectionID);
-            addRelocationForSection(RELo, Value.SectionID);
-          }
-        } else {
-          // Creating Highest, Higher, Hi and Lo relocations for the filled stub
-          // instructions.
-          RelocationEntry REHighest(SectionID,
-                                    StubTargetAddr - Section.getAddress(),
-                                    ELF::R_MIPS_HIGHEST, Value.Addend);
-          RelocationEntry REHigher(SectionID,
-                                   StubTargetAddr - Section.getAddress() + 4,
-                                   ELF::R_MIPS_HIGHER, Value.Addend);
-          RelocationEntry REHi(SectionID,
-                               StubTargetAddr - Section.getAddress() + 12,
-                               ELF::R_MIPS_HI16, Value.Addend);
-          RelocationEntry RELo(SectionID,
-                               StubTargetAddr - Section.getAddress() + 20,
-                               ELF::R_MIPS_LO16, Value.Addend);
-          if (Value.SymbolName) {
-            addRelocationForSymbol(REHighest, Value.SymbolName);
-            addRelocationForSymbol(REHigher, Value.SymbolName);
-            addRelocationForSymbol(REHi, Value.SymbolName);
-            addRelocationForSymbol(RELo, Value.SymbolName);
-          } else {
-            addRelocationForSection(REHighest, Value.SectionID);
-            addRelocationForSection(REHigher, Value.SectionID);
-            addRelocationForSection(REHi, Value.SectionID);
-            addRelocationForSection(RELo, Value.SectionID);
-          }
-        }
-        RelocationEntry RE(SectionID, Offset, RelType, Section.getStubOffset());
-        addRelocationForSection(RE, SectionID);
-        Section.advanceStubOffset(getMaxStubSize());
-      }
-    } else if (RelType == ELF::R_MIPS_HI16 || RelType == ELF::R_MIPS_PCHI16 ||
-               RelType == ELF::R_MIPS_HIGHEST ||
-               RelType == ELF::R_MIPS_HIGHER || RelType == ELF::R_MIPS_LO16 ||
-               RelType == ELF::R_MIPS_PCLO16) {
-      processSimpleRelocation(SectionID, Offset, RelType, Value);
     }
+    if (Value.SymbolName)
+      addRelocationForSymbol(RE, Value.SymbolName);
+    else
+      addRelocationForSection(RE, Value.SectionID);
   } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
     if (RelType == ELF::R_PPC64_REL24) {
       // Determine ABI variant in use for this object.
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
index f37bd0bbaea..fb5da6dd8bb 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
@@ -66,10 +66,8 @@ class RuntimeDyldELF : public RuntimeDyldImpl {
       return 20; // movz; movk; movk; movk; br
     if (Arch == Triple::arm || Arch == Triple::thumb)
       return 8; // 32-bit instruction and 32-bit address
-    else if (IsMipsO32ABI || IsMipsN32ABI)
+    else if (IsMipsO32ABI)
       return 16;
-    else if (IsMipsN64ABI)
-      return 32;
     else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le)
       return 44;
     else if (Arch == Triple::x86_64)
diff --git a/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldELFMips.cpp b/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldELFMips.cpp
index fdca0ce4f3c..926996d6f7b 100644
--- a/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldELFMips.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldELFMips.cpp
@@ -141,10 +141,6 @@ int64_t RuntimeDyldELFMips::evaluateMIPS64Relocation(
     return ((Value + Addend + 0x8000) >> 16) & 0xffff;
   case ELF::R_MIPS_LO16:
     return (Value + Addend) & 0xffff;
-  case ELF::R_MIPS_HIGHER:
-    return ((Value + Addend + 0x80008000) >> 32) & 0xffff;
-  case ELF::R_MIPS_HIGHEST:
-    return ((Value + Addend + 0x800080008000) >> 48) & 0xffff;
   case ELF::R_MIPS_CALL16:
   case ELF::R_MIPS_GOT_DISP:
   case ELF::R_MIPS_GOT_PAGE: {
@@ -219,8 +215,6 @@ void RuntimeDyldELFMips::applyMIPSRelocation(uint8_t *TargetPtr, int64_t Value,
   case ELF::R_MIPS_GPREL16:
   case ELF::R_MIPS_HI16:
   case ELF::R_MIPS_LO16:
-  case ELF::R_MIPS_HIGHER:
-  case ELF::R_MIPS_HIGHEST:
   case ELF::R_MIPS_PC16:
   case ELF::R_MIPS_PCHI16:
   case ELF::R_MIPS_PCLO16:
-- 
2.50.1