R600/SI: implement range reduction for sin/cos

These instructions can only take a limited input range, and return
the constant value 1 out of range. We should do range reduction to
be able to process arbitrary values. Use a FRACT instruction after
normalization to achieve this. Also add a test for constant folding
with the lowered code with unsafe-fp-math enabled.

v2: use DAG lowering instead of intrinsic, adapt test
v3: calculate constant, fold pattern into instruction definition
v4: misc style fixes, add sin-fold testcase, cosmetics

Patch by Grigori Goronzy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213458 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Matt Arsenault 2014-07-19 18:44:39 +00:00
parent 5e1c96a632
commit 18ecf3fff3
5 changed files with 53 additions and 14 deletions

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@ -34,6 +34,9 @@ def AMDGPUDivScaleOp : SDTypeProfile<2, 3,
// This argument to this node is a dword address.
def AMDGPUdwordaddr : SDNode<"AMDGPUISD::DWORDADDR", SDTIntUnaryOp>;
def AMDGPUcos : SDNode<"AMDGPUISD::COS_HW", SDTFPUnaryOp>;
def AMDGPUsin : SDNode<"AMDGPUISD::SIN_HW", SDTFPUnaryOp>;
// out = a - floor(a)
def AMDGPUfract : SDNode<"AMDGPUISD::FRACT", SDTFPUnaryOp>;

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@ -80,6 +80,9 @@ SITargetLowering::SITargetLowering(TargetMachine &TM) :
setOperationAction(ISD::SUBC, MVT::i32, Legal);
setOperationAction(ISD::SUBE, MVT::i32, Legal);
setOperationAction(ISD::FSIN, MVT::f32, Custom);
setOperationAction(ISD::FCOS, MVT::f32, Custom);
// We need to custom lower vector stores from local memory
setOperationAction(ISD::LOAD, MVT::v2i32, Custom);
setOperationAction(ISD::LOAD, MVT::v4i32, Custom);
@ -637,6 +640,9 @@ SDValue SITargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
}
}
case ISD::FSIN:
case ISD::FCOS:
return LowerTrig(Op, DAG);
case ISD::SELECT: return LowerSELECT(Op, DAG);
case ISD::FDIV: return LowerFDIV(Op, DAG);
case ISD::STORE: return LowerSTORE(Op, DAG);
@ -1116,6 +1122,23 @@ SDValue SITargetLowering::LowerSTORE(SDValue Op, SelectionDAG &DAG) const {
return Chain;
}
SDValue SITargetLowering::LowerTrig(SDValue Op, SelectionDAG &DAG) const {
EVT VT = Op.getValueType();
SDValue Arg = Op.getOperand(0);
SDValue FractPart = DAG.getNode(AMDGPUISD::FRACT, SDLoc(Op), VT,
DAG.getNode(ISD::FMUL, SDLoc(Op), VT, Arg,
DAG.getConstantFP(0.5 / M_PI, VT)));
switch (Op.getOpcode()) {
case ISD::FCOS:
return DAG.getNode(AMDGPUISD::COS_HW, SDLoc(Op), VT, FractPart);
case ISD::FSIN:
return DAG.getNode(AMDGPUISD::SIN_HW, SDLoc(Op), VT, FractPart);
default:
llvm_unreachable("Wrong trig opcode");
}
}
//===----------------------------------------------------------------------===//
// Custom DAG optimizations
//===----------------------------------------------------------------------===//

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@ -32,6 +32,7 @@ class SITargetLowering : public AMDGPUTargetLowering {
SDValue LowerFDIV64(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerFDIV(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerSTORE(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerTrig(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerBRCOND(SDValue Op, SelectionDAG &DAG) const;
bool foldImm(SDValue &Operand, int32_t &Immediate,

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@ -1167,8 +1167,12 @@ defm V_SQRT_F32 : VOP1_32 <0x00000033, "V_SQRT_F32",
defm V_SQRT_F64 : VOP1_64 <0x00000034, "V_SQRT_F64",
[(set f64:$dst, (fsqrt f64:$src0))]
>;
defm V_SIN_F32 : VOP1_32 <0x00000035, "V_SIN_F32", []>;
defm V_COS_F32 : VOP1_32 <0x00000036, "V_COS_F32", []>;
defm V_SIN_F32 : VOP1_32 <0x00000035, "V_SIN_F32",
[(set f32:$dst, (AMDGPUsin f32:$src0))]
>;
defm V_COS_F32 : VOP1_32 <0x00000036, "V_COS_F32",
[(set f32:$dst, (AMDGPUcos f32:$src0))]
>;
defm V_NOT_B32 : VOP1_32 <0x00000037, "V_NOT_B32", []>;
defm V_BFREV_B32 : VOP1_32 <0x00000038, "V_BFREV_B32", []>;
defm V_FFBH_U32 : VOP1_32 <0x00000039, "V_FFBH_U32", []>;
@ -2342,16 +2346,6 @@ def : Pat<
(V_MUL_F64 $src0, (V_RCP_F64_e32 $src1), (i64 0))
>;
def : Pat <
(fcos f32:$src0),
(V_COS_F32_e32 (V_MUL_F32_e32 $src0, (V_MOV_B32_e32 CONST.TWO_PI_INV)))
>;
def : Pat <
(fsin f32:$src0),
(V_SIN_F32_e32 (V_MUL_F32_e32 $src0, (V_MOV_B32_e32 CONST.TWO_PI_INV)))
>;
def : Pat <
(int_AMDGPU_cube v4f32:$src),
(INSERT_SUBREG (INSERT_SUBREG (INSERT_SUBREG (INSERT_SUBREG (v4f32 (IMPLICIT_DEF)),

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@ -1,5 +1,6 @@
;RUN: llc < %s -march=r600 -mcpu=redwood | FileCheck %s -check-prefix=EG -check-prefix=FUNC
;RUN: llc < %s -march=r600 -mcpu=SI | FileCheck %s -check-prefix=SI -check-prefix=FUNC
;RUN: llc -march=r600 -mcpu=redwood < %s | FileCheck -check-prefix=EG -check-prefix=FUNC %s
;RUN: llc -march=r600 -mcpu=SI < %s | FileCheck -check-prefix=SI -check-prefix=SI-SAFE -check-prefix=FUNC %s
;RUN: llc -march=r600 -mcpu=SI -enable-unsafe-fp-math < %s | FileCheck -check-prefix=SI -check-prefix=SI-UNSAFE -check-prefix=FUNC %s
;FUNC-LABEL: test
;EG: MULADD_IEEE *
@ -8,6 +9,7 @@
;EG: SIN * T{{[0-9]+\.[XYZW], PV\.[XYZW]}}
;EG-NOT: SIN
;SI: V_MUL_F32
;SI: V_FRACT_F32
;SI: V_SIN_F32
;SI-NOT: V_SIN_F32
@ -17,6 +19,22 @@ define void @test(float addrspace(1)* %out, float %x) #1 {
ret void
}
;FUNC-LABEL: testf
;SI-UNSAFE: 4.774
;SI-UNSAFE: V_MUL_F32
;SI-SAFE: V_MUL_F32
;SI-SAFE: V_MUL_F32
;SI: V_FRACT_F32
;SI: V_SIN_F32
;SI-NOT: V_SIN_F32
define void @testf(float addrspace(1)* %out, float %x) #1 {
%y = fmul float 3.0, %x
%sin = call float @llvm.sin.f32(float %y)
store float %sin, float addrspace(1)* %out
ret void
}
;FUNC-LABEL: testv
;EG: SIN * T{{[0-9]+\.[XYZW], PV\.[XYZW]}}
;EG: SIN * T{{[0-9]+\.[XYZW], PV\.[XYZW]}}