[SPARC][IAS] Add support for v9 DONE, RETRY, SAVED, & RESTORED

Add support for DONE, RETRY, SAVED, and RESTORED (v9 Section A.11 & Section A.47).

Those instructions are used for low-level interrupt handling and register window
management by OS kernels.

Reviewed By: barannikov88

Differential Revision: https://reviews.llvm.org/D144936

Author: koachan

llvm/lib/Target/Sparc/SparcInstrInfo.td

@@ -1743,6 +1743,22 @@ let hasSideEffects = 1 in {
 }
 }
 
+// Section A.11 - DONE and RETRY
+// Section A.47 - SAVED and RESTORED
+let Predicates = [HasV9], rs1 = 0, rs2 = 0 in {
+  let rd = 0 in
+    def DONE : F3_1<2, 0b111110, (outs), (ins), "done", []>;
+
+  let rd = 1 in
+    def RETRY : F3_1<2, 0b111110, (outs), (ins), "retry", []>;
+
+  let rd = 0 in
+    def SAVED : F3_1<2, 0b110001, (outs), (ins), "saved", []>;
+
+  let rd = 1 in
+    def RESTORED : F3_1<2, 0b110001, (outs), (ins), "restored", []>;
+}
+
 // Section A.42 - Prefetch Data
 let Predicates = [HasV9] in {
   def PREFETCHr : F3_1<3, 0b101101,

llvm/test/MC/Disassembler/Sparc/sparc-v9.txt

@@ -137,3 +137,15 @@
 
 # CHECK: prefetch  [%i1+%i2], 1
 0xc3,0x6e,0x40,0x1a
+
+# CHECK: done
+0x81,0xf0,0x00,0x00
+
+# CHECK: retry
+0x83,0xf0,0x00,0x00
+
+# CHECK: saved
+0x81,0x88,0x00,0x00
+
+# CHECK: restored
+0x83,0x88,0x00,0x00

llvm/test/MC/Sparc/sparcv9-instructions.s

@@ -433,3 +433,20 @@
         ! V8-NEXT: prefetch  [ %i1 + %i2 ], 1
         ! V9: prefetch  [%i1+%i2], 1  ! encoding: [0xc3,0x6e,0x40,0x1a]
         prefetch  [ %i1 + %i2 ], 1
+
+        ! V8:      error: instruction requires a CPU feature not currently enabled
+        ! V8-NEXT: done
+        ! V9: done      ! encoding: [0x81,0xf0,0x00,0x00]
+        done
+        ! V8:      error: instruction requires a CPU feature not currently enabled
+        ! V8-NEXT: retry
+        ! V9: retry     ! encoding: [0x83,0xf0,0x00,0x00]
+        retry
+        ! V8:      error: instruction requires a CPU feature not currently enabled
+        ! V8-NEXT: saved
+        ! V9: saved     ! encoding: [0x81,0x88,0x00,0x00]
+        saved
+        ! V8:      error: instruction requires a CPU feature not currently enabled
+        ! V8-NEXT: restored
+        ! V9: restored  ! encoding: [0x83,0x88,0x00,0x00]
+        restored