RFC: PowerPC floating point features

[Michael Eager]

David Edelsohn wrote:
> 	I would prefer feature-based.
> 
> 	TARGET_HARD_FLOAT represents the presence of FPUs.
> 
> 	TARGET_FPRS represents the presence of FP register set because
> one variant used GPRs for FP operations.
> 
> 	E500 then added another variant with double-precision FP in the
> GPRs. 

How about this:

(define_expand "negdf2"
   [(set (match_operand:DF 0 "gpc_reg_operand" "")
     (neg:DF (match_operand:DF 1 "gpc_reg_operand" "")))]
   "TARGET_HARD_FLOAT && TARGET_DOUBLE_FLOAT"
   "")

For an instruction supported on all variants (both BookE and E500)
with a double precision FPU.


(define_expand "negsf2"
   [(set (match_operand:SF 0 "gpc_reg_operand" "")
         (neg:SF (match_operand:SF 1 "gpc_reg_operand" "")))]
   "TARGET_HARD_FLOAT && TARGET_SINGLE_FLOAT"
   "")

For an instruction supported on all variants with a
single precision FPU or a double precision FPU which
supports single precision operations.


(define_insn "floatdidf2"
   [(set (match_operand:DF 0 "gpc_reg_operand" "=f")
	(float:DF (match_operand:DI 1 "gpc_reg_operand" "*f")))]
   "TARGET_POWERPC64 &&
    TARGET_HARD_FLOAT &&
      (TARGET_FPRS && TARGET_DOUBLE_FLOAT)"
   "fcfid %0,%1"
   [(set_attr "type" "fp")])

for an instruction supported on BookE only with double
precision FPU.


(define_insn "*subsf3_gpr"
   [(set (match_operand:SF 0 "gpc_reg_operand" "=r")
	(minus:SF (match_operand:SF 1 "gpc_reg_operand" "r")
		  (match_operand:SF 2 "gpc_reg_operand" "r")))]
   "TARGET_HARD_FLOAT &&
      (!TARGET_FPRS && TARGET_SINGLE_FLOAT)"
   "efssub %0,%1,%2"
   [(set_attr "type" "fp")])

for an instruction on E500 only with single precision FP.


(define_insn "fixuns_truncdfsi2"
   [(set (match_operand:SI 0 "gpc_reg_operand" "=r")
	(unsigned_fix:SI (match_operand:DF 1 "gpc_reg_operand" "r")))]
   "TARGET_HARD_FLOAT &&
      (!TARGET_FPRS && TARGET_DOUBLE_FLOAT"
   "efdctuiz %0,%1"
   [(set_attr "type" "fp")])

for an instruction on E500 only with double precision FP.

-- 
Michael Eager	 eager@eagercon.com
1960 Park Blvd., Palo Alto, CA 94306  650-325-8077