From e56f9085b1e96f0cc302c678f1c00877676e455e Mon Sep 17 00:00:00 2001
From: Anton Korobeynikov <asl@math.spbu.ru>
Date: Sat, 12 Sep 2009 22:21:08 +0000
Subject: [PATCH] Add QPR_VFP2 regclass and add copy_to_regclass nodes, where
 needed to constraint the register usage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81635 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/ARM/ARMBaseInstrInfo.cpp | 14 +++++++++++---
 lib/Target/ARM/ARMInstrNEON.td      | 12 ++++++++----
 lib/Target/ARM/ARMRegisterInfo.td   |  7 +++++++
 3 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index 9da847a5762..52af9786954 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -613,6 +613,7 @@ ARMBaseInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
 
   if (DestRC != SrcRC) {
     // Allow DPR / DPR_VFP2 / DPR_8 cross-class copies
+    // Allow QPR / QPR_VFP2 cross-class copies
     if (DestRC == ARM::DPRRegisterClass) {
       if (SrcRC == ARM::DPR_VFP2RegisterClass ||
           SrcRC == ARM::DPR_8RegisterClass) {
@@ -628,6 +629,10 @@ ARMBaseInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
           SrcRC == ARM::DPR_VFP2RegisterClass) {
       } else
         return false;
+    } else if ((DestRC == ARM::QPRRegisterClass &&
+                SrcRC == ARM::QPR_VFP2RegisterClass) ||
+               (DestRC == ARM::QPR_VFP2RegisterClass &&
+                SrcRC == ARM::QPRRegisterClass)) {
     } else
       return false;
   }
@@ -643,7 +648,8 @@ ARMBaseInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
              (DestRC == ARM::DPR_8RegisterClass)) {
     AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::FCPYD), DestReg)
                    .addReg(SrcReg));
-  } else if (DestRC == ARM::QPRRegisterClass) {
+  } else if (DestRC == ARM::QPRRegisterClass ||
+             DestRC == ARM::QPR_VFP2RegisterClass) {
     BuildMI(MBB, I, DL, get(ARM::VMOVQ), DestReg).addReg(SrcReg);
   } else {
     return false;
@@ -674,7 +680,8 @@ storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
                    .addReg(SrcReg, getKillRegState(isKill))
                    .addFrameIndex(FI).addImm(0));
   } else {
-    assert(RC == ARM::QPRRegisterClass && "Unknown regclass!");
+    assert((RC == ARM::QPRRegisterClass ||
+            RC == ARM::QPR_VFP2RegisterClass) && "Unknown regclass!");
     // FIXME: Neon instructions should support predicates
     BuildMI(MBB, I, DL, get(ARM::VSTRQ)).addReg(SrcReg, getKillRegState(isKill))
       .addFrameIndex(FI).addImm(0);
@@ -700,7 +707,8 @@ loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
     AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::FLDS), DestReg)
                    .addFrameIndex(FI).addImm(0));
   } else {
-    assert(RC == ARM::QPRRegisterClass && "Unknown regclass!");
+    assert((RC == ARM::QPRRegisterClass ||
+            RC == ARM::QPR_VFP2RegisterClass) && "Unknown regclass!");
     // FIXME: Neon instructions should support predicates
     BuildMI(MBB, I, DL, get(ARM::VLDRQ), DestReg).addFrameIndex(FI).addImm(0);
   }
diff --git a/lib/Target/ARM/ARMInstrNEON.td b/lib/Target/ARM/ARMInstrNEON.td
index e9181231609..01b61b5d1dd 100644
--- a/lib/Target/ARM/ARMInstrNEON.td
+++ b/lib/Target/ARM/ARMInstrNEON.td
@@ -2115,9 +2115,11 @@ def : Pat<(extractelt (v4i32 QPR:$src), imm:$lane),
                              (DSubReg_i32_reg imm:$lane))),
                      (SubReg_i32_lane imm:$lane))>;
 def : Pat<(extractelt (v2f32 DPR:$src1), imm:$src2),
-          (EXTRACT_SUBREG DPR:$src1, (SSubReg_f32_reg imm:$src2))>;
+          (EXTRACT_SUBREG (COPY_TO_REGCLASS DPR:$src1, DPR_VFP2),
+                          (SSubReg_f32_reg imm:$src2))>;
 def : Pat<(extractelt (v4f32 QPR:$src1), imm:$src2),
-          (EXTRACT_SUBREG QPR:$src1, (SSubReg_f32_reg imm:$src2))>;
+          (EXTRACT_SUBREG (COPY_TO_REGCLASS QPR:$src1, QPR_VFP2),
+                          (SSubReg_f32_reg imm:$src2))>;
 //def : Pat<(extractelt (v2i64 QPR:$src1), imm:$src2),
 //          (EXTRACT_SUBREG QPR:$src1, (DSubReg_f64_reg imm:$src2))>;
 def : Pat<(extractelt (v2f64 QPR:$src1), imm:$src2),
@@ -2163,9 +2165,11 @@ def : Pat<(insertelt (v4i32 QPR:$src1), GPR:$src2, imm:$lane),
                   (DSubReg_i32_reg imm:$lane)))>;
 
 def : Pat<(v2f32 (insertelt DPR:$src1, SPR:$src2, imm:$src3)),
-          (INSERT_SUBREG DPR:$src1, SPR:$src2, (SSubReg_f32_reg imm:$src3))>;
+          (INSERT_SUBREG (COPY_TO_REGCLASS DPR:$src1, DPR_VFP2),
+                         SPR:$src2, (SSubReg_f32_reg imm:$src3))>;
 def : Pat<(v4f32 (insertelt QPR:$src1, SPR:$src2, imm:$src3)),
-          (INSERT_SUBREG QPR:$src1, SPR:$src2, (SSubReg_f32_reg imm:$src3))>;
+          (INSERT_SUBREG (COPY_TO_REGCLASS QPR:$src1, QPR_VFP2),
+                         SPR:$src2, (SSubReg_f32_reg imm:$src3))>;
 
 //def : Pat<(v2i64 (insertelt QPR:$src1, DPR:$src2, imm:$src3)),
 //          (INSERT_SUBREG QPR:$src1, DPR:$src2, (DSubReg_f64_reg imm:$src3))>;
diff --git a/lib/Target/ARM/ARMRegisterInfo.td b/lib/Target/ARM/ARMRegisterInfo.td
index 9183fa078d4..b20dfc0b61f 100644
--- a/lib/Target/ARM/ARMRegisterInfo.td
+++ b/lib/Target/ARM/ARMRegisterInfo.td
@@ -327,6 +327,13 @@ def QPR : RegisterClass<"ARM", [v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], 128,
   let SubRegClassList = [SPR, SPR, SPR, SPR, DPR, DPR];
 }
 
+// Subset of QPR that have 32-bit SPR subregs.
+def QPR_VFP2 : RegisterClass<"ARM", [v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
+                             128,
+                             [Q0,  Q1,  Q2,  Q3,  Q4,  Q5,  Q6,  Q7]> {
+  let SubRegClassList = [SPR, SPR, SPR, SPR, DPR, DPR];
+}
+
 // Condition code registers.
 def CCR : RegisterClass<"ARM", [i32], 32, [CPSR]>;