From: Evan Cheng <evan.cheng@apple.com>
Date: Wed, 24 Jan 2007 08:53:17 +0000 (+0000)
Subject: Use PC relative ldr to load from a constantpool in Thumb mode.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=012f2d97b78e4eb9128f1d491f2c177768dbe527;p=oota-llvm.git

Use PC relative ldr to load from a constantpool in Thumb mode.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33484 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/ARM/ARMConstantIslandPass.cpp b/lib/Target/ARM/ARMConstantIslandPass.cpp
index 183bde88243..2b5227a1602 100644
--- a/lib/Target/ARM/ARMConstantIslandPass.cpp
+++ b/lib/Target/ARM/ARMConstantIslandPass.cpp
@@ -245,6 +245,9 @@ void ARMConstantIslands::InitialFunctionScan(MachineFunction &Fn,
           case ARMII::AddrModeT4:
             MaxOffs = 1 << (5+2);
             break;
+          case ARMII::AddrModeTs:
+            MaxOffs = 1 << (8+2);
+            break;
           }
           
           // Remember that this is a user of a CP entry.
diff --git a/lib/Target/ARM/ARMISelDAGToDAG.cpp b/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 9b06adda9c1..4c6fce6efa5 100644
--- a/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -380,6 +380,9 @@ ARMDAGToDAGISel::SelectThumbAddrModeRI5(SDOperand Op, SDOperand N,
     SDOperand TmpBase, TmpOffImm;
     if (SelectThumbAddrModeSP(Op, N, TmpBase, TmpOffImm))
       return false;  // We want to select tLDRspi / tSTRspi instead.
+    if (N.getOpcode() == ARMISD::Wrapper &&
+        N.getOperand(0).getOpcode() == ISD::TargetConstantPool)
+      return false;  // We want to select tLDRpci instead.
   }
 
   if (N.getOpcode() != ISD::ADD) {
@@ -505,14 +508,20 @@ SDNode *ARMDAGToDAGISel::Select(SDOperand Op) {
       SDOperand CPIdx =
         CurDAG->getTargetConstantPool(ConstantInt::get(Type::Int32Ty, Val),
                                       TLI.getPointerTy());
-      SDOperand Ops[] = {
-        CPIdx, 
-        CurDAG->getRegister(0, MVT::i32),
-        CurDAG->getTargetConstant(0, MVT::i32),
-        CurDAG->getEntryNode()
-      };
-      SDNode *ResNode = 
-        CurDAG->getTargetNode(ARM::LDR, MVT::i32, MVT::Other, Ops, 4);
+
+      SDNode *ResNode;
+      if (Subtarget->isThumb())
+        ResNode = CurDAG->getTargetNode(ARM::tLDRpci, MVT::i32, MVT::Other,
+                                        CPIdx, CurDAG->getEntryNode());
+      else {
+        SDOperand Ops[] = {
+          CPIdx, 
+          CurDAG->getRegister(0, MVT::i32),
+          CurDAG->getTargetConstant(0, MVT::i32),
+          CurDAG->getEntryNode()
+        };
+        ResNode = CurDAG->getTargetNode(ARM::LDR, MVT::i32, MVT::Other, Ops, 4);
+      }
       ReplaceUses(Op, SDOperand(ResNode, 0));
       return NULL;
     }
diff --git a/lib/Target/ARM/ARMInstrThumb.td b/lib/Target/ARM/ARMInstrThumb.td
index fa7afea976d..677b6f4133e 100644
--- a/lib/Target/ARM/ARMInstrThumb.td
+++ b/lib/Target/ARM/ARMInstrThumb.td
@@ -220,10 +220,14 @@ def tLDRSH : TI2<(ops GPR:$dst, t_addrmode_rr:$addr),
                  "ldrsh $dst, $addr",
                  [(set GPR:$dst, (sextloadi16 t_addrmode_rr:$addr))]>;
 
-// def tLDRpci
 def tLDRspi : TIs<(ops GPR:$dst, t_addrmode_sp:$addr),
                   "ldr $dst, $addr",
                   [(set GPR:$dst, (load t_addrmode_sp:$addr))]>;
+
+// Load tconstpool
+def tLDRpci : TIs<(ops GPR:$dst, i32imm:$addr),
+                  "ldr $dst, $addr",
+                  [(set GPR:$dst, (load (ARMWrapper tconstpool:$addr)))]>;
 } // isLoad
 
 let isStore = 1 in {