[AArch64] Extend single-operand FP insns to match Arm ARM (NFCI)

The Armv8.3-A reference manual defines floating-point data-processing
instructions with one source operand to have an opcode of 6 bits
[20:15]. The current class in tablegen, BaseSingleOperandFPData, only
allows [18:15]. This was ok because [20:19] could only be '00', with
other encodings unallocated. Armv8.5-A brings in the FRINT group of
instructions which use other values for these bits.

This patch refactors the existing class a bit to allow using the full 6
bits of the opcode, as defined in the Arm ARM.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52474

llvm-svn: 343120

diff --git a/llvm/lib/Target/AArch64/AArch64InstrFormats.td b/llvm/lib/Target/AArch64/AArch64InstrFormats.td
index df6a63ba6fad798919ce01a5c23cdadf8dc1c99c..1ad87558b639af64f54c6989399d9a4318a24d98 100644 (file)
--- a/llvm/lib/Target/AArch64/AArch64InstrFormats.td
+++ b/llvm/lib/Target/AArch64/AArch64InstrFormats.td
@@ -4401,7 +4401,7 @@ multiclass FPConversion<string asm> {
 //---
 
 let mayLoad = 0, mayStore = 0, hasSideEffects = 0 in
-class BaseSingleOperandFPData<bits<4> opcode, RegisterClass regtype,
+class BaseSingleOperandFPData<bits<6> opcode, RegisterClass regtype,
                               ValueType vt, string asm, SDPatternOperator node>
     : I<(outs regtype:$Rd), (ins regtype:$Rn), asm, "\t$Rd, $Rn", "",
          [(set (vt regtype:$Rd), (node (vt regtype:$Rn)))]>,
@@ -4409,8 +4409,8 @@ class BaseSingleOperandFPData<bits<4> opcode, RegisterClass regtype,
   bits<5> Rd;
   bits<5> Rn;
   let Inst{31-24} = 0b00011110;
-  let Inst{21-19} = 0b100;
-  let Inst{18-15} = opcode;
+  let Inst{21}    = 0b1;
+  let Inst{20-15} = opcode;
   let Inst{14-10} = 0b10000;
   let Inst{9-5}   = Rn;
   let Inst{4-0}   = Rd;
@@ -4418,16 +4418,17 @@ class BaseSingleOperandFPData<bits<4> opcode, RegisterClass regtype,
 
 multiclass SingleOperandFPData<bits<4> opcode, string asm,
                                SDPatternOperator node = null_frag> {
-  def Hr : BaseSingleOperandFPData<opcode, FPR16, f16, asm, node> {
+
+  def Hr : BaseSingleOperandFPData<{0b00,opcode}, FPR16, f16, asm, node> {
     let Inst{23-22} = 0b11; // 16-bit size flag
     let Predicates = [HasFullFP16];
   }
 
-  def Sr : BaseSingleOperandFPData<opcode, FPR32, f32, asm, node> {
+  def Sr : BaseSingleOperandFPData<{0b00,opcode}, FPR32, f32, asm, node> {
     let Inst{23-22} = 0b00; // 32-bit size flag
   }
 
-  def Dr : BaseSingleOperandFPData<opcode, FPR64, f64, asm, node> {
+  def Dr : BaseSingleOperandFPData<{0b00,opcode}, FPR64, f64, asm, node> {
     let Inst{23-22} = 0b01; // 64-bit size flag
   }
 }