[PowerPC] Do not legalize vector FDIV without VSX

Quite a while ago, we legalized these nodes as we added custom
handling for reciprocal estimates in the back end. We have since
moved to target-independent combines but neglected to turn off
legalization. As a result, we can now get selection failures on
non-VSX subtargets as evidenced in the listed PR.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=47373
This commit is contained in:
Nemanja Ivanovic 2020-09-02 15:30:19 -05:00
parent 53df1fb508
commit cba7028fdb
2 changed files with 181 additions and 7 deletions

View File

@ -860,7 +860,7 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
setOperationAction(ISD::MUL, MVT::v4f32, Legal);
setOperationAction(ISD::FMA, MVT::v4f32, Legal);
if (TM.Options.UnsafeFPMath || Subtarget.hasVSX()) {
if (Subtarget.hasVSX()) {
setOperationAction(ISD::FDIV, MVT::v4f32, Legal);
setOperationAction(ISD::FSQRT, MVT::v4f32, Legal);
}
@ -1234,12 +1234,6 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
setTargetDAGCombine(ISD::SELECT_CC);
}
// Use reciprocal estimates.
if (TM.Options.UnsafeFPMath) {
setTargetDAGCombine(ISD::FDIV);
setTargetDAGCombine(ISD::FSQRT);
}
if (Subtarget.hasP9Altivec()) {
setTargetDAGCombine(ISD::ABS);
setTargetDAGCombine(ISD::VSELECT);

View File

@ -0,0 +1,180 @@
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -mtriple=powerpc64-unknown-freebsd13.0 \
; RUN: -mcpu=ppc64 -ppc-asm-full-reg-names < %s | FileCheck %s
@a = local_unnamed_addr global float* null, align 8
; Function Attrs: nounwind
define void @d() local_unnamed_addr #0 {
; CHECK-LABEL: d:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: mflr r0
; CHECK-NEXT: std r0, 16(r1)
; CHECK-NEXT: stdu r1, -208(r1)
; CHECK-NEXT: addis r3, r2, .LC0@toc@ha
; CHECK-NEXT: std r29, 184(r1) # 8-byte Folded Spill
; CHECK-NEXT: ld r3, .LC0@toc@l(r3)
; CHECK-NEXT: std r30, 192(r1) # 8-byte Folded Spill
; CHECK-NEXT: ld r29, 0(r3)
; CHECK-NEXT: bl c
; CHECK-NEXT: nop
; CHECK-NEXT: mr r30, r3
; CHECK-NEXT: bl b
; CHECK-NEXT: nop
; CHECK-NEXT: cmpwi r30, 1
; CHECK-NEXT: blt cr0, .LBB0_9
; CHECK-NEXT: # %bb.1: # %for.body.preheader
; CHECK-NEXT: cmplwi r30, 4
; CHECK-NEXT: clrldi r4, r30, 32
; CHECK-NEXT: li r5, 0
; CHECK-NEXT: blt cr0, .LBB0_7
; CHECK-NEXT: # %bb.2: # %vector.memcheck
; CHECK-NEXT: rldic r6, r30, 2, 30
; CHECK-NEXT: add r7, r3, r6
; CHECK-NEXT: cmpld r29, r7
; CHECK-NEXT: add r6, r29, r6
; CHECK-NEXT: bc 4, lt, .LBB0_4
; CHECK-NEXT: # %bb.3: # %vector.memcheck
; CHECK-NEXT: cmpld r3, r6
; CHECK-NEXT: bc 12, lt, .LBB0_7
; CHECK-NEXT: .LBB0_4: # %vector.ph
; CHECK-NEXT: rlwinm r5, r4, 0, 0, 29
; CHECK-NEXT: li r7, 15
; CHECK-NEXT: addi r6, r5, -4
; CHECK-NEXT: addi r8, r1, 144
; CHECK-NEXT: rldicl r6, r6, 62, 2
; CHECK-NEXT: addi r9, r1, 128
; CHECK-NEXT: addi r6, r6, 1
; CHECK-NEXT: addi r10, r1, 160
; CHECK-NEXT: mtctr r6
; CHECK-NEXT: li r6, 0
; CHECK-NEXT: addi r11, r1, 112
; CHECK-NEXT: .LBB0_5: # %vector.body
; CHECK-NEXT: #
; CHECK-NEXT: add r12, r3, r6
; CHECK-NEXT: lvx v3, r3, r6
; CHECK-NEXT: lvx v5, r12, r7
; CHECK-NEXT: add r12, r29, r6
; CHECK-NEXT: lvsl v2, r3, r6
; CHECK-NEXT: vperm v2, v3, v5, v2
; CHECK-NEXT: lvx v3, r29, r6
; CHECK-NEXT: lvx v5, r12, r7
; CHECK-NEXT: lvsl v4, r29, r6
; CHECK-NEXT: stvx v2, 0, r8
; CHECK-NEXT: vperm v2, v3, v5, v4
; CHECK-NEXT: stvx v2, 0, r9
; CHECK-NEXT: lfs f0, 156(r1)
; CHECK-NEXT: lfs f1, 140(r1)
; CHECK-NEXT: fdivs f0, f1, f0
; CHECK-NEXT: lfs f1, 136(r1)
; CHECK-NEXT: stfs f0, 172(r1)
; CHECK-NEXT: lfs f0, 152(r1)
; CHECK-NEXT: fdivs f0, f1, f0
; CHECK-NEXT: lfs f1, 132(r1)
; CHECK-NEXT: stfs f0, 168(r1)
; CHECK-NEXT: lfs f0, 148(r1)
; CHECK-NEXT: fdivs f0, f1, f0
; CHECK-NEXT: lfs f1, 128(r1)
; CHECK-NEXT: stfs f0, 164(r1)
; CHECK-NEXT: lfs f0, 144(r1)
; CHECK-NEXT: fdivs f0, f1, f0
; CHECK-NEXT: stfs f0, 160(r1)
; CHECK-NEXT: lvx v2, 0, r10
; CHECK-NEXT: stvx v2, 0, r11
; CHECK-NEXT: ld r0, 112(r1)
; CHECK-NEXT: stdx r0, r29, r6
; CHECK-NEXT: addi r6, r6, 16
; CHECK-NEXT: ld r0, 120(r1)
; CHECK-NEXT: std r0, 8(r12)
; CHECK-NEXT: bdnz .LBB0_5
; CHECK-NEXT: # %bb.6: # %middle.block
; CHECK-NEXT: cmpld r5, r4
; CHECK-NEXT: beq cr0, .LBB0_9
; CHECK-NEXT: .LBB0_7: # %for.body.preheader18
; CHECK-NEXT: sldi r6, r5, 2
; CHECK-NEXT: sub r5, r4, r5
; CHECK-NEXT: addi r6, r6, -4
; CHECK-NEXT: add r3, r3, r6
; CHECK-NEXT: add r4, r29, r6
; CHECK-NEXT: mtctr r5
; CHECK-NEXT: .LBB0_8: # %for.body
; CHECK-NEXT: #
; CHECK-NEXT: lfsu f0, 4(r4)
; CHECK-NEXT: lfsu f1, 4(r3)
; CHECK-NEXT: fdivs f0, f0, f1
; CHECK-NEXT: stfs f0, 0(r4)
; CHECK-NEXT: bdnz .LBB0_8
; CHECK-NEXT: .LBB0_9: # %for.end
; CHECK-NEXT: ld r30, 192(r1) # 8-byte Folded Reload
; CHECK-NEXT: ld r29, 184(r1) # 8-byte Folded Reload
; CHECK-NEXT: addi r1, r1, 208
; CHECK-NEXT: ld r0, 16(r1)
; CHECK-NEXT: mtlr r0
; CHECK-NEXT: blr
entry:
%0 = load float*, float** @a, align 8
%call = call signext i32 bitcast (i32 (...)* @c to i32 ()*)() #2
%call1 = call float* bitcast (float* (...)* @b to float* ()*)() #2
%cmp11 = icmp sgt i32 %call, 0
br i1 %cmp11, label %for.body.preheader, label %for.end
for.body.preheader: ; preds = %entry
%wide.trip.count = zext i32 %call to i64
%min.iters.check = icmp ult i32 %call, 4
br i1 %min.iters.check, label %for.body.preheader18, label %vector.memcheck
vector.memcheck: ; preds = %for.body.preheader
%scevgep = getelementptr float, float* %0, i64 %wide.trip.count
%scevgep15 = getelementptr float, float* %call1, i64 %wide.trip.count
%bound0 = icmp ult float* %0, %scevgep15
%bound1 = icmp ult float* %call1, %scevgep
%found.conflict = and i1 %bound0, %bound1
br i1 %found.conflict, label %for.body.preheader18, label %vector.ph
vector.ph: ; preds = %vector.memcheck
%n.vec = and i64 %wide.trip.count, 4294967292
br label %vector.body
vector.body: ; preds = %vector.body, %vector.ph
%index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
%1 = getelementptr inbounds float, float* %call1, i64 %index
%2 = bitcast float* %1 to <4 x float>*
%wide.load = load <4 x float>, <4 x float>* %2, align 4
%3 = getelementptr inbounds float, float* %0, i64 %index
%4 = bitcast float* %3 to <4 x float>*
%wide.load17 = load <4 x float>, <4 x float>* %4, align 4
%5 = fdiv reassoc nsz arcp afn <4 x float> %wide.load17, %wide.load
%6 = bitcast float* %3 to <4 x float>*
store <4 x float> %5, <4 x float>* %6, align 4
%index.next = add i64 %index, 4
%7 = icmp eq i64 %index.next, %n.vec
br i1 %7, label %middle.block, label %vector.body
middle.block: ; preds = %vector.body
%cmp.n = icmp eq i64 %n.vec, %wide.trip.count
br i1 %cmp.n, label %for.end, label %for.body.preheader18
for.body.preheader18: ; preds = %middle.block, %vector.memcheck, %for.body.preheader
%indvars.iv.ph = phi i64 [ 0, %vector.memcheck ], [ 0, %for.body.preheader ], [ %n.vec, %middle.block ]
br label %for.body
for.body: ; preds = %for.body.preheader18, %for.body
%indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ %indvars.iv.ph, %for.body.preheader18 ]
%arrayidx = getelementptr inbounds float, float* %call1, i64 %indvars.iv
%8 = load float, float* %arrayidx, align 4
%arrayidx3 = getelementptr inbounds float, float* %0, i64 %indvars.iv
%9 = load float, float* %arrayidx3, align 4
%div = fdiv reassoc nsz arcp afn float %9, %8
store float %div, float* %arrayidx3, align 4
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
br i1 %exitcond.not, label %for.end, label %for.body
for.end: ; preds = %for.body, %middle.block, %entry
ret void
}
declare signext i32 @c(...) local_unnamed_addr #1
declare float* @b(...) local_unnamed_addr #1
attributes #0 = { nounwind }