[llvm] Add FPMR register and update dependencies of FP8 instructions (PR #102910)

[Paul Walker via llvm-commits]

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@@ -10306,15 +10316,47 @@ class sve2_fp8_mla_long_long_by_indexed_elem<bits<2> TT, string mnemonic>
   let Constraints = "$Zda = $_Zda";
   let DestructiveInstType = DestructiveOther;
   let ElementSize         = ZPR32.ElementSize;
+  let Uses = [FPMR, FPCR];
+}
+
+class sve_fp8_dot_indexed<bit bf, ZPRRegOp dst_ty, Operand iop_ty, string mnemonic>
+: I<(outs dst_ty:$Zda), (ins dst_ty:$_Zda, ZPR8:$Zn, ZPR3b8:$Zm, iop_ty:$iop),
+    mnemonic, "\t$Zda, $Zn, $Zm$iop", "", []>, Sched<[]> {
+  bits<5> Zda;
+  bits<5> Zn;
+  bits<3> Zm;
+  let Inst{31-23} = 0b011001000;
+  let Inst{22}    = bf;
+  let Inst{21}    = 0b1;
+  let Inst{18-16} = Zm;
+  let Inst{15-12} = 0b0100;
+  let Inst{10}    = 0b1;
+  let Inst{9-5}   = Zn;
+  let Inst{4-0}   = Zda;
+
+  let Uses = [FPMR, FPCR];
+  let Constraints = "$Zda = $_Zda";
+  let DestructiveInstType = DestructiveOther;
+  let hasSideEffects = 0;
+  let mayRaiseFPException = 1;
 }
 
 // FP8 Widening Dot-Product - Indexed Group
-multiclass sve2_fp8_dot_indexed<string mnemonic>{
-  def NAME : sve_float_dot_indexed<0b0, ZPR16, ZPR8, ZPR3b8, VectorIndexH, mnemonic> {
+multiclass sve2_fp8_dot_indexed_h<string asm>{
+  def NAME : sve_fp8_dot_indexed<0b0, ZPR16, VectorIndexH, asm> {
     bits<3> iop;
+
     let Inst{20-19} = iop{2-1};
-    let Inst{11} = iop{0};
-    let Inst{10} = 0b1;
+    let Inst{11}    = iop{0};
+  }
+}
+
+multiclass sve2_fp8_dot_indexed_s<string asm>{
+  def NAME : sve_fp8_dot_indexed<0b1, ZPR32, VectorIndexS32b, asm> {
+    bits<3> iop;
+
+    let Inst{20-19} = iop{1-0};
+    let Inst{11}    = 0b0;
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paulwalker-arm wrote:

With the above suggestion, this line can be deleted.

https://github.com/llvm/llvm-project/pull/102910