Beginning of expanding all current mips16 macro/pseudo instruction sequences.

This expansion will be moved to expandISelPseudos as soon as I can figure
out how to do that. There are other instructions which use this 
ExpandFEXT_T8I816_ins and as soon as I have finished expanding them all,
I will delete the macro asm string text so it has no way to be used
in the future.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175413 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Mips/Mips16InstrInfo.cpp

@@ -21,6 +21,7 @@
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/RegisterScavenging.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/TargetRegistry.h"
 
@@ -135,6 +136,9 @@ bool Mips16InstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator MI) const {
   switch(MI->getDesc().getOpcode()) {
   default:
     return false;
+  case Mips::BtnezT8CmpX16:
+    ExpandFEXT_T8I816_ins(MBB, MI, Mips::BtnezX16, Mips::CmpRxRy16);
+    break;
   case Mips::RetRA16:
     ExpandRetRA16(MBB, MI, Mips::JrcRa16);
     break;
@@ -399,6 +403,17 @@ void Mips16InstrInfo::ExpandRetRA16(MachineBasicBlock &MBB,
   BuildMI(MBB, I, I->getDebugLoc(), get(Opc));
 }
 
+
+void Mips16InstrInfo::ExpandFEXT_T8I816_ins(
+  MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
+  unsigned BtOpc, unsigned CmpOpc) const {
+  unsigned regX = I->getOperand(0).getReg();
+  unsigned regY = I->getOperand(1).getReg();
+  MachineBasicBlock *target = I->getOperand(2).getMBB();
+  BuildMI(MBB, I, I->getDebugLoc(), get(CmpOpc)).addReg(regX).addReg(regY);
+  BuildMI(MBB, I, I->getDebugLoc(), get(BtOpc)).addMBB(target);
+
+}
 const MCInstrDesc &Mips16InstrInfo::AddiuSpImm(int64_t Imm) const {
   if (validSpImm8(Imm))
     return get(Mips::AddiuSpImm16);

lib/Target/Mips/Mips16InstrInfo.h

@@ -115,7 +115,9 @@ private:
                                      MachineBasicBlock &MBB,
                                      MachineBasicBlock::iterator I) const;
 
-
+  void ExpandFEXT_T8I816_ins(MachineBasicBlock &MBB,
+                             MachineBasicBlock::iterator I,
+                             unsigned BtOpc, unsigned CmpOpc) const;
 };
 
 }

lib/Target/Mips/Mips16InstrInfo.td

@@ -516,7 +516,9 @@ def BnezRxImmX16: FEXT_RI16_B_ins<0b00101, "bnez", IIAlu>, cbranch16;
 // Purpose: Branch on T Equal to Zero (Extended)
 // To test special register T then do a PC-relative conditional branch.
 //
-def BteqzX16: FEXT_I816_ins<0b000, "bteqz", IIAlu>, cbranch16;
+def BteqzX16: FEXT_I816_ins<0b000, "bteqz", IIAlu>, cbranch16 {
+  let Uses = [T8];
+}
 
 def BteqzT8CmpX16: FEXT_T8I816_ins<"bteqz", "cmp">, cbranch16;
 
@@ -537,7 +539,9 @@ def BteqzT8SltiuX16: FEXT_T8I8I16_ins<"bteqz", "sltiu">,
 // Purpose: Branch on T Not Equal to Zero (Extended)
 // To test special register T then do a PC-relative conditional branch.
 //
-def BtnezX16: FEXT_I816_ins<0b001, "btnez", IIAlu> ,cbranch16;
+def BtnezX16: FEXT_I816_ins<0b001, "btnez", IIAlu> ,cbranch16 {
+  let Uses = [T8];
+}
 
 def BtnezT8CmpX16: FEXT_T8I816_ins<"btnez", "cmp">, cbranch16;
 
@@ -552,6 +556,16 @@ def BtnezT8SltiX16: FEXT_T8I8I16_ins<"btnez", "slti">, cbranch16;
 def BtnezT8SltiuX16: FEXT_T8I8I16_ins<"btnez", "sltiu">,
   cbranch16;
 
+//
+// Format: CMP rx, ry MIPS16e
+// Purpose: Compare
+// To compare the contents of two GPRs.
+//
+def CmpRxRy16: FRR16_ins<0b01010, "cmp", IIAlu> {
+  let Defs = [T8];
+}
+
+
 //
 // Format: DIV rx, ry MIPS16e
 // Purpose: Divide Word

test/CodeGen/Mips/seleq.ll

@@ -0,0 +1,95 @@
+; RUN: llc -march=mipsel -mcpu=mips16 -relocation-model=pic < %s | FileCheck %s -check-prefix=16
+
+@t = global i32 10, align 4
+@f = global i32 199, align 4
+@a = global i32 1, align 4
+@b = global i32 10, align 4
+@c = global i32 1, align 4
+@z1 = common global i32 0, align 4
+@z2 = common global i32 0, align 4
+@z3 = common global i32 0, align 4
+@z4 = common global i32 0, align 4
+
+define void @calc_seleq() nounwind "target-cpu"="mips32" "target-features"="+o32,+mips32" {
+entry:
+  %0 = load i32* @a, align 4
+  %1 = load i32* @b, align 4
+  %cmp = icmp eq i32 %0, %1
+  br i1 %cmp, label %cond.true, label %cond.false
+
+cond.true:                                        ; preds = %entry
+  %2 = load i32* @f, align 4
+  br label %cond.end
+
+cond.false:                                       ; preds = %entry
+  %3 = load i32* @t, align 4
+  br label %cond.end
+
+cond.end:                                         ; preds = %cond.false, %cond.true
+  %cond = phi i32 [ %2, %cond.true ], [ %3, %cond.false ]
+  store i32 %cond, i32* @z1, align 4
+  %4 = load i32* @b, align 4
+  %5 = load i32* @a, align 4
+  %cmp1 = icmp eq i32 %4, %5
+  br i1 %cmp1, label %cond.true2, label %cond.false3
+
+cond.true2:                                       ; preds = %cond.end
+  %6 = load i32* @f, align 4
+  br label %cond.end4
+
+cond.false3:                                      ; preds = %cond.end
+  %7 = load i32* @t, align 4
+  br label %cond.end4
+
+cond.end4:                                        ; preds = %cond.false3, %cond.true2
+  %cond5 = phi i32 [ %6, %cond.true2 ], [ %7, %cond.false3 ]
+  store i32 %cond5, i32* @z2, align 4
+  %8 = load i32* @c, align 4
+  %9 = load i32* @a, align 4
+  %cmp6 = icmp eq i32 %8, %9
+  br i1 %cmp6, label %cond.true7, label %cond.false8
+
+cond.true7:                                       ; preds = %cond.end4
+  %10 = load i32* @t, align 4
+  br label %cond.end9
+
+cond.false8:                                      ; preds = %cond.end4
+  %11 = load i32* @f, align 4
+  br label %cond.end9
+
+cond.end9:                                        ; preds = %cond.false8, %cond.true7
+  %cond10 = phi i32 [ %10, %cond.true7 ], [ %11, %cond.false8 ]
+  store i32 %cond10, i32* @z3, align 4
+  %12 = load i32* @a, align 4
+  %13 = load i32* @c, align 4
+  %cmp11 = icmp eq i32 %12, %13
+  br i1 %cmp11, label %cond.true12, label %cond.false13
+
+cond.true12:                                      ; preds = %cond.end9
+  %14 = load i32* @t, align 4
+  br label %cond.end14
+
+cond.false13:                                     ; preds = %cond.end9
+  %15 = load i32* @f, align 4
+  br label %cond.end14
+
+cond.end14:                                       ; preds = %cond.false13, %cond.true12
+  %cond15 = phi i32 [ %14, %cond.true12 ], [ %15, %cond.false13 ]
+  store i32 %cond15, i32* @z4, align 4
+  ret void
+}
+
+attributes #0 = { nounwind "target-cpu"="mips32" "target-features"="+o32,+mips32" }
+
+; 16:	cmp	${{[0-9]+}}, ${{[0-9]+}}
+; 16:	btnez	$BB{{[0-9]+}}_{{[0-9]}}
+
+; 16:	cmp	${{[0-9]+}}, ${{[0-9]+}}
+; 16:	btnez	$BB{{[0-9]+}}_{{[0-9]}}
+
+; 16:	cmp	${{[0-9]+}}, ${{[0-9]+}}
+; 16:	btnez	$BB{{[0-9]+}}_{{[0-9]}}
+
+; 16:	cmp	${{[0-9]+}}, ${{[0-9]+}}
+; 16:	btnez	$BB{{[0-9]+}}_{{[0-9]}}
+