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[PATCH][ARM] Handle FMA code in rtx costs.
- From: Kyrill Tkachov <kyrylo dot tkachov at arm dot com>
- To: GCC Patches <gcc-patches at gcc dot gnu dot org>
- Cc: Ramana Radhakrishnan <ramana dot radhakrishnan at arm dot com>, Richard Earnshaw <Richard dot Earnshaw at arm dot com>
- Date: Mon, 24 Mar 2014 17:15:39 +0000
- Subject: [PATCH][ARM] Handle FMA code in rtx costs.
- Authentication-results: sourceware.org; auth=none
Hi all,
This patch adds proper rtx costing logic for floating point fma operations on
arm. It also handles the fma+neg combinations that can be expressed with
vfms,vfnma or vfnms instructions.
Not much else to say here...
Tested and boostrapped on arm-none-linux-gnueabihf.
Ok for next stage1?
Thanks,
Kyrill
2014-03-24 Kyrylo Tkachov <kyrylo.tkachov@arm.com>
* config/arm/arm.c (arm_new_rtx_costs): Handle FMA.commit 9cebc525c432e4a87ead5b513b70c99dff6628c8
Author: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date: Thu Mar 20 09:13:06 2014 +0000
[ARM] Cost FMA operations properly.
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 5619ebd..e7a0530 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -10673,6 +10673,36 @@ arm_new_rtx_costs (rtx x, enum rtx_code code, enum rtx_code outer_code,
*cost = LIBCALL_COST (1);
return false;
+ case FMA:
+ if (TARGET_32BIT && TARGET_HARD_FLOAT && TARGET_FMA)
+ {
+ rtx op0 = XEXP (x, 0);
+ rtx op1 = XEXP (x, 1);
+ rtx op2 = XEXP (x, 2);
+
+ *cost = COSTS_N_INSNS (1);
+
+ /* vfms or vfnma. */
+ if (GET_CODE (op0) == NEG)
+ op0 = XEXP (op0, 0);
+
+ /* vfnms or vfnma. */
+ if (GET_CODE (op2) == NEG)
+ op2 = XEXP (op2, 0);
+
+ *cost += rtx_cost (op0, FMA, 0, speed_p);
+ *cost += rtx_cost (op1, FMA, 1, speed_p);
+ *cost += rtx_cost (op2, FMA, 2, speed_p);
+
+ if (speed_p)
+ *cost += extra_cost->fp[mode ==DFmode].fma;
+
+ return true;
+ }
+
+ *cost = LIBCALL_COST (1);
+ return false;
+
case FIX:
case UNSIGNED_FIX:
if (TARGET_HARD_FLOAT)