[llvm] r315748 - AMDGPU: Look for src mods before fp_extend
Matt Arsenault via llvm-commits
llvm-commits at lists.llvm.org
Fri Oct 13 13:45:49 PDT 2017
Author: arsenm
Date: Fri Oct 13 13:45:49 2017
New Revision: 315748
URL: http://llvm.org/viewvc/llvm-project?rev=315748&view=rev
Log:
AMDGPU: Look for src mods before fp_extend
When selecting modifiers for mad_mix instructions,
look at fneg/fabs that occur before the conversion.
Modified:
llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
llvm/trunk/test/CodeGen/AMDGPU/fpext-free.ll
llvm/trunk/test/CodeGen/AMDGPU/mad-mix.ll
Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp?rev=315748&r1=315747&r2=315748&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp Fri Oct 13 13:45:49 2017
@@ -1982,15 +1982,31 @@ bool AMDGPUDAGToDAGISel::SelectVOP3PMadM
assert(Src.getValueType() == MVT::f16);
Src = stripBitcast(Src);
+ // Be careful about folding modifiers if we already have an abs. fneg is
+ // applied last, so we don't want to apply an earlier fneg.
+ if ((Mods & SISrcMods::ABS) == 0) {
+ unsigned ModsTmp;
+ SelectVOP3ModsImpl(Src, Src, ModsTmp);
+
+ if ((ModsTmp & SISrcMods::NEG) != 0)
+ Mods ^= SISrcMods::NEG;
+
+ if ((ModsTmp & SISrcMods::ABS) != 0)
+ Mods |= SISrcMods::ABS;
+ }
+
// op_sel/op_sel_hi decide the source type and source.
// If the source's op_sel_hi is set, it indicates to do a conversion from fp16.
// If the sources's op_sel is set, it picks the high half of the source
// register.
Mods |= SISrcMods::OP_SEL_1;
- if (isExtractHiElt(Src, Src))
+ if (isExtractHiElt(Src, Src)) {
Mods |= SISrcMods::OP_SEL_0;
+ // TODO: Should we try to look for neg/abs here?
+ }
+
return true;
}
Modified: llvm/trunk/test/CodeGen/AMDGPU/fpext-free.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/fpext-free.ll?rev=315748&r1=315747&r2=315748&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/fpext-free.ll (original)
+++ llvm/trunk/test/CodeGen/AMDGPU/fpext-free.ll Fri Oct 13 13:45:49 2017
@@ -254,11 +254,9 @@ entry:
; fold (fsub (fpext (fneg (fmul, x, y))), z)
; -> (fneg (fma (fpext x), (fpext y), z))
-; FIXME: Should be able to fold fneg
; GCN-LABEL: {{^}}fsub_fpext_fneg_fmul_f16_to_f32:
; GCN: s_waitcnt
-; GFX9-F32FLUSH-NEXT: v_xor_b32_e32 v1, 0x8000, v1
-; GFX9-F32FLUSH-NEXT: v_mad_mix_f32 v0, v0, v1, -v2 op_sel_hi:[1,1,0]{{$}}
+; GFX9-F32FLUSH-NEXT: v_mad_mix_f32 v0, v0, -v1, -v2 op_sel_hi:[1,1,0]{{$}}
; GFX9-F32FLUSH-NEXT: s_setpc_b64
; GFX9-F32DENORM-NEXT: v_mul_f16_e64 v0, v0, -v1
@@ -277,11 +275,9 @@ entry:
; fold (fsub (fneg (fpext (fmul, x, y))), z)
; -> (fneg (fma (fpext x)), (fpext y), z)
-; FIXME: Should be able to fold fneg
; GCN-LABEL: {{^}}fsub_fneg_fpext_fmul_f16_to_f32:
; GCN: s_waitcnt
-; GFX9-F32FLUSH-NEXT: v_xor_b32_e32 v1, 0x8000, v1
-; GFX9-F32FLUSH-NEXT: v_mad_mix_f32 v0, v0, v1, -v2 op_sel_hi:[1,1,0]{{$}}
+; GFX9-F32FLUSH-NEXT: v_mad_mix_f32 v0, v0, -v1, -v2 op_sel_hi:[1,1,0]{{$}}
; GFX9-F32FLUSH-NEXT: s_setpc_b64
; GFX9-F32DENORM-NEXT: v_mul_f16_e64 v0, v0, -v1
Modified: llvm/trunk/test/CodeGen/AMDGPU/mad-mix.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/mad-mix.ll?rev=315748&r1=315747&r2=315748&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/mad-mix.ll (original)
+++ llvm/trunk/test/CodeGen/AMDGPU/mad-mix.ll Fri Oct 13 13:45:49 2017
@@ -398,6 +398,106 @@ define float @v_mad_mix_f32_f16lo_f16lo_
ret float %result
}
+; GCN-LABEL: {{^}}v_mad_mix_f32_negprecvtf16lo_f16lo_f16lo:
+; GFX9: s_waitcnt
+; GFX9-NEXT: v_mad_mix_f32 v0, -v0, v1, v2 ; encoding
+; GFX9-NEXT: s_setpc_b64
+
+; CIVI: v_mad_f32
+define float @v_mad_mix_f32_negprecvtf16lo_f16lo_f16lo(i32 %src0.arg, half %src1, half %src2) #0 {
+ %src0.arg.bc = bitcast i32 %src0.arg to <2 x half>
+ %src0 = extractelement <2 x half> %src0.arg.bc, i32 0
+ %src0.neg = fsub half -0.0, %src0
+ %src0.ext = fpext half %src0.neg to float
+ %src1.ext = fpext half %src1 to float
+ %src2.ext = fpext half %src2 to float
+; %src0.ext.neg = fsub float -0.0, %src0.ext
+ %result = tail call float @llvm.fmuladd.f32(float %src0.ext, float %src1.ext, float %src2.ext)
+ ret float %result
+}
+
+; Make sure we don't fold pre-cvt fneg if we already have a fabs
+; GCN-LABEL: {{^}}v_mad_mix_f32_precvtnegf16hi_abs_f16lo_f16lo:
+; GFX9: s_waitcnt
+define float @v_mad_mix_f32_precvtnegf16hi_abs_f16lo_f16lo(i32 %src0.arg, half %src1, half %src2) #0 {
+ %src0.arg.bc = bitcast i32 %src0.arg to <2 x half>
+ %src0 = extractelement <2 x half> %src0.arg.bc, i32 1
+ %src0.neg = fsub half -0.0, %src0
+ %src0.ext = fpext half %src0.neg to float
+ %src0.ext.abs = call float @llvm.fabs.f32(float %src0.ext)
+ %src1.ext = fpext half %src1 to float
+ %src2.ext = fpext half %src2 to float
+ %result = tail call float @llvm.fmuladd.f32(float %src0.ext.abs, float %src1.ext, float %src2.ext)
+ ret float %result
+}
+
+; GCN-LABEL: {{^}}v_mad_mix_f32_precvtabsf16hi_f16lo_f16lo:
+; GFX9: s_waitcnt
+; GFX9-NEXT: v_mad_mix_f32 v0, |v0|, v1, v2 op_sel:[1,0,0]
+; GFX9-NEXT: s_setpc_b64
+define float @v_mad_mix_f32_precvtabsf16hi_f16lo_f16lo(i32 %src0.arg, half %src1, half %src2) #0 {
+ %src0.arg.bc = bitcast i32 %src0.arg to <2 x half>
+ %src0 = extractelement <2 x half> %src0.arg.bc, i32 1
+ %src0.abs = call half @llvm.fabs.f16(half %src0)
+ %src0.ext = fpext half %src0.abs to float
+ %src1.ext = fpext half %src1 to float
+ %src2.ext = fpext half %src2 to float
+ %result = tail call float @llvm.fmuladd.f32(float %src0.ext, float %src1.ext, float %src2.ext)
+ ret float %result
+}
+
+; GCN-LABEL: {{^}}v_mad_mix_f32_preextractfneg_f16hi_f16lo_f16lo:
+; GFX9: s_waitcnt
+; GFX9-NEXT: v_mad_mix_f32 v0, -v0, v1, v2 op_sel:[1,0,0]
+; GFX9-NEXT: s_setpc_b64
+define float @v_mad_mix_f32_preextractfneg_f16hi_f16lo_f16lo(i32 %src0.arg, half %src1, half %src2) #0 {
+ %src0.arg.bc = bitcast i32 %src0.arg to <2 x half>
+ %fneg = fsub <2 x half> <half -0.0, half -0.0>, %src0.arg.bc
+ %src0 = extractelement <2 x half> %fneg, i32 1
+ %src0.ext = fpext half %src0 to float
+ %src1.ext = fpext half %src1 to float
+ %src2.ext = fpext half %src2 to float
+ %result = tail call float @llvm.fmuladd.f32(float %src0.ext, float %src1.ext, float %src2.ext)
+ ret float %result
+}
+
+; FIXME: Should be able to fold
+; GCN-LABEL: {{^}}v_mad_mix_f32_preextractfabs_f16hi_f16lo_f16lo:
+; GFX9: s_waitcnt
+; GFX9-NEXT: v_and_b32_e32 v0, 0x7fff0000, v0
+; GFX9-NEXT: v_mad_mix_f32 v0, v0, v1, v2 op_sel:[1,0,0]
+; GFX9-NEXT: s_setpc_b64
+define float @v_mad_mix_f32_preextractfabs_f16hi_f16lo_f16lo(i32 %src0.arg, half %src1, half %src2) #0 {
+ %src0.arg.bc = bitcast i32 %src0.arg to <2 x half>
+ %fabs = call <2 x half> @llvm.fabs.v2f16(<2 x half> %src0.arg.bc)
+ %src0 = extractelement <2 x half> %fabs, i32 1
+ %src0.ext = fpext half %src0 to float
+ %src1.ext = fpext half %src1 to float
+ %src2.ext = fpext half %src2 to float
+ %result = tail call float @llvm.fmuladd.f32(float %src0.ext, float %src1.ext, float %src2.ext)
+ ret float %result
+}
+
+; FIXME: Should be able to fold
+; GCN-LABEL: {{^}}v_mad_mix_f32_preextractfabsfneg_f16hi_f16lo_f16lo:
+; GFX9: s_waitcnt
+; GFX9-NEXT: v_and_b32_e32 v0, 0x7fff0000, v0
+; GFX9-NEXT: v_mad_mix_f32 v0, -v0, v1, v2 op_sel:[1,0,0]
+; GFX9-NEXT: s_setpc_b64
+define float @v_mad_mix_f32_preextractfabsfneg_f16hi_f16lo_f16lo(i32 %src0.arg, half %src1, half %src2) #0 {
+ %src0.arg.bc = bitcast i32 %src0.arg to <2 x half>
+ %fabs = call <2 x half> @llvm.fabs.v2f16(<2 x half> %src0.arg.bc)
+ %fneg.fabs = fsub <2 x half> <half -0.0, half -0.0>, %fabs
+ %src0 = extractelement <2 x half> %fneg.fabs, i32 1
+ %src0.ext = fpext half %src0 to float
+ %src1.ext = fpext half %src1 to float
+ %src2.ext = fpext half %src2 to float
+ %result = tail call float @llvm.fmuladd.f32(float %src0.ext, float %src1.ext, float %src2.ext)
+ ret float %result
+}
+
+declare half @llvm.fabs.f16(half) #2
+declare <2 x half> @llvm.fabs.v2f16(<2 x half>) #2
declare float @llvm.fabs.f32(float) #2
declare float @llvm.minnum.f32(float, float) #2
declare float @llvm.maxnum.f32(float, float) #2
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