ARM: add fstmx and fldmx instructions for assembly

These instructions are deprecated oddities, but we still need to be able to
disassemble (and reassemble) them if and when they're encountered.

Patch by Amaury de la Vieuville.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183011 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 30 insertions, 1 deletions

diff --git a/lib/Target/ARM/ARMInstrVFP.td b/lib/Target/ARM/ARMInstrVFP.td
index b5a896c699..2380528e13 100644
--- a/lib/Target/ARM/ARMInstrVFP.td
+++ b/lib/Target/ARM/ARMInstrVFP.td
@@ -224,7 +224,36 @@ defm : VFPDTAnyInstAlias<"vpop${p}", "$r",
 defm : VFPDTAnyInstAlias<"vpop${p}", "$r",
                          (VLDMDIA_UPD SP, pred:$p, dpr_reglist:$r)>;
 
-// FLDMX, FSTMX - mixing S/D registers for pre-armv6 cores
+// FLDMX, FSTMX - Load and store multiple unknown precision registers for
+// pre-armv6 cores.
+// These instruction are deprecated so we don't want them to get selected.
+multiclass vfp_ldstx_mult<string asm, bit L_bit> {
+  // Unknown precision
+  def XIA :
+    AXXI4<(outs), (ins GPR:$Rn, pred:$p, dpr_reglist:$regs, variable_ops),
+          IndexModeNone, !strconcat(asm, "iax${p}\t$Rn, $regs"), "", []> {
+    let Inst{24-23} = 0b01;       // Increment After
+    let Inst{21}    = 0;          // No writeback
+    let Inst{20}    = L_bit;
+  }
+  def XIA_UPD :
+    AXXI4<(outs GPR:$wb), (ins GPR:$Rn, pred:$p, dpr_reglist:$regs, variable_ops),
+          IndexModeUpd, !strconcat(asm, "iax${p}\t$Rn!, $regs"), "$Rn = $wb", []> {
+    let Inst{24-23} = 0b01;         // Increment After
+    let Inst{21}    = 1;            // Writeback
+    let Inst{20}    = L_bit;
+  }
+  def XDB_UPD :
+    AXXI4<(outs GPR:$wb), (ins GPR:$Rn, pred:$p, dpr_reglist:$regs, variable_ops),
+          IndexModeUpd, !strconcat(asm, "dbx${p}\t$Rn!, $regs"), "$Rn = $wb", []> {
+    let Inst{24-23} = 0b10;         // Decrement Before
+    let Inst{21}    = 1;
+    let Inst{20}    = L_bit;
+  }
+}
+
+defm FLDM : vfp_ldstx_mult<"fldm", 1>;
+defm FSTM : vfp_ldstx_mult<"fstm", 0>;
 
 //===----------------------------------------------------------------------===//
 // FP Binary Operations.