From 3aa035fa0c27d3ea2a834868f680bcbfe7eb0de7 Mon Sep 17 00:00:00 2001
From: Bruno Cardoso Lopes <bruno.cardoso@gmail.com>
Date: Fri, 30 Dec 2011 21:04:30 +0000
Subject: [PATCH] Improve Mips JIT.

Implement encoder methods getJumpTargetOpValue and getBranchTargetOpValue
for jmptarget and brtarget Mips tablegen operand types in the code emitter
for old-style JIT. Rename the pc relative relocation for branches - new
name is Mips::reloc_mips_pc16.

Patch by Sasa Stankovic

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147382 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/Mips/MipsCodeEmitter.cpp | 15 ++++++++++++---
 lib/Target/Mips/MipsJITInfo.cpp     |  2 +-
 lib/Target/Mips/MipsRelocations.h   |  4 ++--
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/lib/Target/Mips/MipsCodeEmitter.cpp b/lib/Target/Mips/MipsCodeEmitter.cpp
index a3b260fa364..fd768f27a59 100644
--- a/lib/Target/Mips/MipsCodeEmitter.cpp
+++ b/lib/Target/Mips/MipsCodeEmitter.cpp
@@ -163,7 +163,7 @@ unsigned MipsCodeEmitter::getRelocation(const MachineInstr &MI,
     return Mips::reloc_mips_26;
   if ((Form == MipsII::FrmI || Form == MipsII::FrmFI)
        && MI.isBranch())
-    return Mips::reloc_mips_branch;
+    return Mips::reloc_mips_pc16;
   if (Form == MipsII::FrmI && MI.getOpcode() == Mips::LUi)
     return Mips::reloc_mips_hi;
   return Mips::reloc_mips_lo;
@@ -171,13 +171,22 @@ unsigned MipsCodeEmitter::getRelocation(const MachineInstr &MI,
 
 unsigned MipsCodeEmitter::getJumpTargetOpValue(const MachineInstr &MI,
                                                unsigned OpNo) const {
-  // FIXME: implement
+  MachineOperand MO = MI.getOperand(OpNo);
+  if (MO.isGlobal())
+    emitGlobalAddress(MO.getGlobal(), getRelocation(MI, MO), true);
+  else if (MO.isSymbol())
+    emitExternalSymbolAddress(MO.getSymbolName(), getRelocation(MI, MO));
+  else if (MO.isMBB())
+    emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO));
+  else
+    llvm_unreachable("Unexpected jump target operand kind.");
   return 0;
 }
 
 unsigned MipsCodeEmitter::getBranchTargetOpValue(const MachineInstr &MI,
                                                  unsigned OpNo) const {
-  // FIXME: implement
+  MachineOperand MO = MI.getOperand(OpNo);
+  emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO));
   return 0;
 }
 
diff --git a/lib/Target/Mips/MipsJITInfo.cpp b/lib/Target/Mips/MipsJITInfo.cpp
index a0ee722996d..27d5918c8b6 100644
--- a/lib/Target/Mips/MipsJITInfo.cpp
+++ b/lib/Target/Mips/MipsJITInfo.cpp
@@ -200,7 +200,7 @@ void MipsJITInfo::relocate(void *Function, MachineRelocation *MR,
     intptr_t ResultPtr = (intptr_t) MR->getResultPointer();
 
     switch ((Mips::RelocationType) MR->getRelocationType()) {
-    case Mips::reloc_mips_branch:
+    case Mips::reloc_mips_pc16:
       ResultPtr = (((ResultPtr - (intptr_t) RelocPos) - 4) >> 2) & 0xffff;
       *((unsigned*) RelocPos) |= (unsigned) ResultPtr;
       break;
diff --git a/lib/Target/Mips/MipsRelocations.h b/lib/Target/Mips/MipsRelocations.h
index 66d1bfd993f..69f6dceff81 100644
--- a/lib/Target/Mips/MipsRelocations.h
+++ b/lib/Target/Mips/MipsRelocations.h
@@ -20,10 +20,10 @@
 namespace llvm {
   namespace Mips{
     enum RelocationType {
-      // reloc_mips_branch - pc relative relocation for branches. The lower 18
+      // reloc_mips_pc16 - pc relative relocation for branches. The lower 18
       // bits of the difference between the branch target and the branch
       // instruction, shifted right by 2.
-      reloc_mips_branch = 1,
+      reloc_mips_pc16 = 1,
 
       // reloc_mips_hi - upper 16 bits of the address (modified by +1 if the
       // lower 16 bits of the address is negative).