Switch ARM BR_JTm and BR_JTr instructions to be MC-expanded pseudos.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120303 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 95 insertions, 43 deletions

diff --git a/lib/Target/ARM/ARMAsmPrinter.cpp b/lib/Target/ARM/ARMAsmPrinter.cpp
index b8cdbd3edf..84ddab99aa 100644
--- a/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -936,32 +936,74 @@ void ARMAsmPrinter::EmitInstruction(const MachineInstr *MI) {
     EmitJump2Table(MI);
     return;
   }
-  case ARM::tBR_JTr:
-  case ARM::BR_JTr:
-  case ARM::BR_JTm: {
+  case ARM::tBR_JTr: {
     // Lower and emit the instruction itself, then the jump table following it.
     MCInst TmpInst;
     // FIXME: The branch instruction is really a pseudo. We should xform it
     // explicitly.
     LowerARMMachineInstrToMCInst(MI, TmpInst, *this);
     OutStreamer.EmitInstruction(TmpInst);
+
+    // Output the data for the jump table itself
+    EmitJumpTable(MI);
+    return;
+  }
+  case ARM::BR_JTr: {
+    // Lower and emit the instruction itself, then the jump table following it.
+    // mov pc, target
+    MCInst TmpInst;
+    TmpInst.setOpcode(ARM::MOVr);
+    TmpInst.addOperand(MCOperand::CreateReg(ARM::PC));
+    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
+    // Add predicate operands.
+    TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
+    TmpInst.addOperand(MCOperand::CreateReg(0));
+    OutStreamer.EmitInstruction(TmpInst);
+
+    // Output the data for the jump table itself
+    EmitJumpTable(MI);
+    return;
+  }
+  case ARM::BR_JTm: {
+    // Lower and emit the instruction itself, then the jump table following it.
+    // ldr pc, target
+    MCInst TmpInst;
+    if (MI->getOperand(1).getReg() == 0) {
+      // literal offset
+      TmpInst.setOpcode(ARM::LDRi12);
+      TmpInst.addOperand(MCOperand::CreateReg(ARM::PC));
+      TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
+      TmpInst.addOperand(MCOperand::CreateImm(MI->getOperand(2).getImm()));
+    } else {
+      TmpInst.setOpcode(ARM::LDRrs);
+      TmpInst.addOperand(MCOperand::CreateReg(ARM::PC));
+      TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
+      TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg()));
+      TmpInst.addOperand(MCOperand::CreateImm(0));
+    }
+    // Add predicate operands.
+    TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
+    TmpInst.addOperand(MCOperand::CreateReg(0));
+    OutStreamer.EmitInstruction(TmpInst);
+
+    // Output the data for the jump table itself
     EmitJumpTable(MI);
     return;
   }
   case ARM::BR_JTadd: {
     // Lower and emit the instruction itself, then the jump table following it.
     // add pc, target, idx
-    MCInst AddInst;
-    AddInst.setOpcode(ARM::ADDrr);
-    AddInst.addOperand(MCOperand::CreateReg(ARM::PC));
-    AddInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
-    AddInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg()));
+    MCInst TmpInst;
+    TmpInst.setOpcode(ARM::ADDrr);
+    TmpInst.addOperand(MCOperand::CreateReg(ARM::PC));
+    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
+    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg()));
     // Add predicate operands.
-    AddInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
-    AddInst.addOperand(MCOperand::CreateReg(0));
+    TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
+    TmpInst.addOperand(MCOperand::CreateReg(0));
     // Add 's' bit operand (always reg0 for this)
-    AddInst.addOperand(MCOperand::CreateReg(0));
-    OutStreamer.EmitInstruction(AddInst);
+    TmpInst.addOperand(MCOperand::CreateReg(0));
+    OutStreamer.EmitInstruction(TmpInst);
 
     // Output the data for the jump table itself
     EmitJumpTable(MI);
diff --git a/lib/Target/ARM/ARMInstrFormats.td b/lib/Target/ARM/ARMInstrFormats.td
index d6f9781ea4..a5f89d6e49 100644
--- a/lib/Target/ARM/ARMInstrFormats.td
+++ b/lib/Target/ARM/ARMInstrFormats.td
@@ -508,6 +508,24 @@ class AI3ldstidx<bits<4> op, bit op20, bit isLd, bit isPre, dag oops, dag iops,
   let Inst{15-12} = Rt;           // Rt
   let Inst{7-4}   = op;
 }
+class AI3stridx<bits<4> op, bit isByte, bit isPre, dag oops, dag iops,
+                IndexMode im, Format f, InstrItinClass itin, string opc,
+                string asm, string cstr, list<dag> pattern>
+  : AI2ldstidx<0, isByte, isPre, oops, iops, im, f, itin, opc, asm, cstr,
+               pattern> {
+  // AM3 store w/ two operands: (GPR, am3offset)
+  bits<14> offset;
+  bits<4> Rt;
+  bits<4> Rn;
+  let Inst{27-25} = 0b000;
+  let Inst{23}    = offset{8};
+  let Inst{22}    = offset{9};
+  let Inst{19-16} = Rn;
+  let Inst{15-12} = Rt;           // Rt
+  let Inst{11-8}  = offset{7-4};  // imm7_4/zero
+  let Inst{7-4}   = op;
+  let Inst{3-0}   = offset{3-0};  // imm3_0/Rm
+}
 
 // stores
 class AI3str<bits<4> op, dag oops, dag iops, Format f, InstrItinClass itin,
diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index 588ff8a7a3..dbd2701605 100644
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -1427,29 +1427,21 @@ let isBranch = 1, isTerminator = 1 in {
       let Inst{23-0} = target;
     }
 
-    let isNotDuplicable = 1, isIndirectBranch = 1,
-        // FIXME: $imm field is not specified by asm string.  Mark as cgonly.
-        isCodeGenOnly = 1 in {
-    def BR_JTr : JTI<(outs), (ins GPR:$target, jtblock_operand:$jt, i32imm:$id),
-                      IIC_Br, "mov\tpc, $target$jt",
+    let isNotDuplicable = 1, isIndirectBranch = 1 in {
+    def BR_JTr : ARMPseudoInst<(outs),
+                      (ins GPR:$target, jtblock_operand:$jt, i32imm:$id),
+                      IIC_Br,// "mov\tpc, $target$jt",
                       [(ARMbrjt GPR:$target, tjumptable:$jt, imm:$id)]> {
-      let Inst{11-4}  = 0b00000000;
-      let Inst{15-12} = 0b1111;
-      let Inst{20}    = 0; // S Bit
-      let Inst{24-21} = 0b1101;
-      let Inst{27-25} = 0b000;
+      let SZ = SizeSpecial;
     }
-    def BR_JTm : JTI<(outs),
+    // FIXME: This shouldn't use the generic "addrmode2," but rather be split
+    // into i12 and rs suffixed versions.
+    def BR_JTm : ARMPseudoInst<(outs),
                      (ins addrmode2:$target, jtblock_operand:$jt, i32imm:$id),
-                     IIC_Br, "ldr\tpc, $target$jt",
+                     IIC_Br,
                      [(ARMbrjt (i32 (load addrmode2:$target)), tjumptable:$jt,
                        imm:$id)]> {
-      let Inst{15-12} = 0b1111;
-      let Inst{20}    = 1; // L bit
-      let Inst{21}    = 0; // W bit
-      let Inst{22}    = 0; // B bit
-      let Inst{24}    = 1; // P bit
-      let Inst{27-25} = 0b011;
+      let SZ = SizeSpecial;
     }
     def BR_JTadd : ARMPseudoInst<(outs),
                    (ins GPR:$target, GPR:$idx, jtblock_operand:$jt, i32imm:$id),
@@ -1730,19 +1722,19 @@ def STRB_POST: AI2stridx<1, 0, (outs GPR:$Rn_wb),
                      [(set GPR:$Rn_wb, (post_truncsti8 GPR:$Rt,
                                         GPR:$Rn, am2offset:$offset))]>;
 
-def STRH_PRE : AI3sthpr<(outs GPR:$base_wb),
-                     (ins GPR:$src, GPR:$base,am3offset:$offset),
-                     StMiscFrm, IIC_iStore_ru,
-                     "strh", "\t$src, [$base, $offset]!", "$base = $base_wb",
-                     [(set GPR:$base_wb,
-                      (pre_truncsti16 GPR:$src, GPR:$base,am3offset:$offset))]>;
-
-def STRH_POST: AI3sthpo<(outs GPR:$base_wb),
-                     (ins GPR:$src, GPR:$base,am3offset:$offset),
-                     StMiscFrm, IIC_iStore_bh_ru,
-                     "strh", "\t$src, [$base], $offset", "$base = $base_wb",
-                     [(set GPR:$base_wb, (post_truncsti16 GPR:$src,
-                                          GPR:$base, am3offset:$offset))]>;
+def STRH_PRE : AI3stridx<0b1011, 0, 1, (outs GPR:$Rn_wb),
+                     (ins GPR:$Rt, GPR:$Rn, am3offset:$offset),
+                     IndexModePre, StMiscFrm, IIC_iStore_ru,
+                     "strh", "\t$Rt, [$Rn, $offset]!", "$Rn = $Rn_wb",
+                     [(set GPR:$Rn_wb,
+                      (pre_truncsti16 GPR:$Rt, GPR:$Rn, am3offset:$offset))]>;
+
+def STRH_POST: AI3stridx<0b1011, 0, 0, (outs GPR:$Rn_wb),
+                     (ins GPR:$Rt, GPR:$Rn, am3offset:$offset),
+                     IndexModePost, StMiscFrm, IIC_iStore_bh_ru,
+                     "strh", "\t$Rt, [$Rn], $offset", "$Rn = $Rn_wb",
+                     [(set GPR:$Rn_wb, (post_truncsti16 GPR:$Rt,
+                                        GPR:$Rn, am3offset:$offset))]>;
 
 // For disassembly only
 def STRD_PRE : AI3stdpr<(outs GPR:$base_wb),