AArch64: remove post-encoder method from FCMP (immediate) instructions.

The work done by the post-encoder (setting architecturally unused bits to 0 as
required) can be done by the existing operand that covers the "#0.0". This
removes at least one use of the discouraged PostEncoderMethod uses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176261 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 16 deletions

diff --git a/lib/Target/AArch64/AArch64InstrInfo.td b/lib/Target/AArch64/AArch64InstrInfo.td
index 78c4ad16d7..319ec97cfc 100644
--- a/lib/Target/AArch64/AArch64InstrInfo.td
+++ b/lib/Target/AArch64/AArch64InstrInfo.td
@@ -1945,43 +1945,41 @@ def fpz32 : Operand<f32>,
             ComplexPattern<f32, 1, "SelectFPZeroOperand", [fpimm]> {
   let ParserMatchClass = fpzero_asmoperand;
   let PrintMethod = "printFPZeroOperand";
+  let DecoderMethod = "DecodeFPZeroOperand";
 }
 
 def fpz64 : Operand<f64>,
             ComplexPattern<f64, 1, "SelectFPZeroOperand", [fpimm]> {
   let ParserMatchClass = fpzero_asmoperand;
   let PrintMethod = "printFPZeroOperand";
+  let DecoderMethod = "DecodeFPZeroOperand";
 }
 
-multiclass A64I_fpcmpSignal<bits<2> type, bit imm, dag ins, string asmop2,
-                            dag pattern> {
+multiclass A64I_fpcmpSignal<bits<2> type, bit imm, dag ins, dag pattern> {
   def _quiet : A64I_fpcmp<0b0, 0b0, type, 0b00, {0b0, imm, 0b0, 0b0, 0b0},
-                          (outs), ins, !strconcat("fcmp\t$Rn, ", asmop2),
-                          [pattern], NoItinerary> {
+                          (outs), ins, "fcmp\t$Rn, $Rm", [pattern],
+                          NoItinerary> {
     let Defs = [NZCV];
   }
 
   def _sig : A64I_fpcmp<0b0, 0b0, type, 0b00, {0b1, imm, 0b0, 0b0, 0b0},
-                        (outs), ins, !strconcat("fcmpe\t$Rn, ", asmop2),
-                        [], NoItinerary> {
+                        (outs), ins, "fcmpe\t$Rn, $Rm", [], NoItinerary> {
     let Defs = [NZCV];
   }
 }
 
-defm FCMPss : A64I_fpcmpSignal<0b00, 0b0, (ins FPR32:$Rn, FPR32:$Rm), "$Rm",
+defm FCMPss : A64I_fpcmpSignal<0b00, 0b0, (ins FPR32:$Rn, FPR32:$Rm),
                                (set NZCV, (A64cmp (f32 FPR32:$Rn), FPR32:$Rm))>;
-defm FCMPdd : A64I_fpcmpSignal<0b01, 0b0, (ins FPR64:$Rn, FPR64:$Rm), "$Rm",
+defm FCMPdd : A64I_fpcmpSignal<0b01, 0b0, (ins FPR64:$Rn, FPR64:$Rm),
                                (set NZCV, (A64cmp (f64 FPR64:$Rn), FPR64:$Rm))>;
 
-// What would be Rm should be written as 0, but anything is valid for
-// disassembly so we can't set the bits
-let PostEncoderMethod = "fixFCMPImm" in {
-  defm FCMPsi : A64I_fpcmpSignal<0b00, 0b1, (ins FPR32:$Rn, fpz32:$Imm), "$Imm",
-                              (set NZCV, (A64cmp (f32 FPR32:$Rn), fpz32:$Imm))>;
+// What would be Rm should be written as 0; note that even though it's called
+// "$Rm" here to fit in with the InstrFormats, it's actually an immediate.
+defm FCMPsi : A64I_fpcmpSignal<0b00, 0b1, (ins FPR32:$Rn, fpz32:$Rm),
+                               (set NZCV, (A64cmp (f32 FPR32:$Rn), fpz32:$Rm))>;
 
-  defm FCMPdi : A64I_fpcmpSignal<0b01, 0b1, (ins FPR64:$Rn, fpz64:$Imm), "$Imm",
-                              (set NZCV, (A64cmp (f64 FPR64:$Rn), fpz64:$Imm))>;
-}
+defm FCMPdi : A64I_fpcmpSignal<0b01, 0b1, (ins FPR64:$Rn, fpz64:$Rm),
+                               (set NZCV, (A64cmp (f64 FPR64:$Rn), fpz64:$Rm))>;
 
 
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