[AMDGPU] Always emit SI_KILL_I1_PSEUDO for uniform floating point branches.

Author: Konstantina Mitropoulou

llvm/lib/Target/AMDGPU/AMDGPU.td

@@ -2498,6 +2498,9 @@ def HasNotMADIntraFwdBug : Predicate<"!Subtarget->hasMADIntraFwdBug()">;
 def HasSALUFloatInsts : Predicate<"Subtarget->hasSALUFloatInsts()">,
   AssemblerPredicate<(all_of FeatureSALUFloatInsts)>;
 
+def NotHasSALUFloatInsts : Predicate<"!Subtarget->hasSALUFloatInsts()">,
+  AssemblerPredicate<(all_of (not FeatureSALUFloatInsts))>;
+
 def HasPseudoScalarTrans : Predicate<"Subtarget->hasPseudoScalarTrans()">,
   AssemblerPredicate<(all_of FeaturePseudoScalarTrans)>;
 

llvm/lib/Target/AMDGPU/SIInstructions.td

@@ -1063,6 +1063,7 @@ def : GCNPat <
   (SI_KILL_I1_PSEUDO SCSrc_i1:$src, -1)
 >;
 
+let SubtargetPredicate = NotHasSALUFloatInsts in
 def : GCNPat <
   (int_amdgcn_kill (i1 (setcc f32:$src, InlineImmFP32:$imm, cond:$cond))),
   (SI_KILL_F32_COND_IMM_PSEUDO VSrc_b32:$src, (bitcast_fpimm_to_i32 $imm), (cond_as_i32imm $cond))