llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-llvm-transforms Author: Matt Arsenault (arsenm) <details> <summary>Changes</summary> This already recognized that if both inputs are positive, the result is positive. Extend this to the mirror situation with negative inputs. Also special case fadd x, x. Canonically, fmul x, 2 is fadd x, x. We can tell the sign bit won't change, and 0 will propagate. --- Full diff: https://github.com/llvm/llvm-project/pull/174123.diff 2 Files Affected: - (modified) llvm/lib/Analysis/ValueTracking.cpp (+24-4) - (modified) llvm/test/Transforms/Attributor/nofpclass.ll (+23-23) ``````````diff diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index cf7c6796f76c7..df435df311d0c 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -5619,14 +5619,22 @@ void computeKnownFPClass(const Value *V, const APInt &DemandedElts, computeKnownFPClass(Op->getOperand(1), DemandedElts, InterestedSrcs, KnownRHS, Q, Depth + 1); + // Special case fadd x, x, which is the canonical form of fmul x, 2. + bool SameOperands = Op->getOperand(0) == Op->getOperand(1); + if (SameOperands) + KnownLHS = KnownRHS; + if ((WantNaN && KnownRHS.isKnownNeverNaN()) || (WantNegative && KnownRHS.cannotBeOrderedLessThanZero()) || WantNegZero || Opc == Instruction::FSub) { - // RHS is canonically cheaper to compute. Skip inspecting the LHS if - // there's no point. - computeKnownFPClass(Op->getOperand(0), DemandedElts, InterestedSrcs, - KnownLHS, Q, Depth + 1); + if (!SameOperands) { + // RHS is canonically cheaper to compute. Skip inspecting the LHS if + // there's no point. + computeKnownFPClass(Op->getOperand(0), DemandedElts, InterestedSrcs, + KnownLHS, Q, Depth + 1); + } + // Adding positive and negative infinity produces NaN. // TODO: Check sign of infinities. if (KnownLHS.isKnownNeverNaN() && KnownRHS.isKnownNeverNaN() && @@ -5640,6 +5648,10 @@ void computeKnownFPClass(const Value *V, const APInt &DemandedElts, if (KnownLHS.cannotBeOrderedLessThanZero() && KnownRHS.cannotBeOrderedLessThanZero()) Known.knownNot(KnownFPClass::OrderedLessThanZeroMask); + if (KnownLHS.cannotBeOrderedGreaterThanZero() && + KnownRHS.cannotBeOrderedGreaterThanZero()) + Known.knownNot(KnownFPClass::OrderedGreaterThanZeroMask); + if (!F) break; @@ -5647,6 +5659,14 @@ void computeKnownFPClass(const Value *V, const APInt &DemandedElts, Op->getType()->getScalarType()->getFltSemantics(); DenormalMode Mode = F->getDenormalMode(FltSem); + if (SameOperands) { + // Doubling 0 will give the same 0. + if (KnownRHS.isKnownNeverLogicalPosZero(Mode)) + Known.knownNot(fcPosZero); + if (KnownRHS.isKnownNeverLogicalNegZero(Mode)) + Known.knownNot(fcNegZero); + } + // (fadd x, 0.0) is guaranteed to return +0.0, not -0.0. if ((KnownLHS.isKnownNeverLogicalNegZero(Mode) || KnownRHS.isKnownNeverLogicalNegZero(Mode)) && diff --git a/llvm/test/Transforms/Attributor/nofpclass.ll b/llvm/test/Transforms/Attributor/nofpclass.ll index a0f418a70457b..209eaae1a167e 100644 --- a/llvm/test/Transforms/Attributor/nofpclass.ll +++ b/llvm/test/Transforms/Attributor/nofpclass.ll @@ -3043,7 +3043,7 @@ define float @fadd_double_no_inf(float nofpclass(inf) %arg) { define float @fadd_double_no_zero(float nofpclass(zero) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define nofpclass(nzero) float @fadd_double_no_zero +; CHECK-LABEL: define nofpclass(zero) float @fadd_double_no_zero ; CHECK-SAME: (float nofpclass(zero) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3076,7 +3076,7 @@ define float @fadd_double_known_positive(float nofpclass(ninf nnorm nsub nzero) define float @fadd_double_known_positive_non0(float nofpclass(ninf nnorm nsub zero) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define nofpclass(ninf nzero nsub nnorm) float @fadd_double_known_positive_non0 +; CHECK-LABEL: define nofpclass(ninf zero nsub nnorm) float @fadd_double_known_positive_non0 ; CHECK-SAME: (float nofpclass(ninf zero nsub nnorm) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3087,7 +3087,7 @@ define float @fadd_double_known_positive_non0(float nofpclass(ninf nnorm nsub ze define float @fadd_double_known_negative_or_zero(float nofpclass(pinf pnorm psub) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_known_negative_or_zero +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_double_known_negative_or_zero ; CHECK-SAME: (float nofpclass(pinf psub pnorm) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3098,7 +3098,7 @@ define float @fadd_double_known_negative_or_zero(float nofpclass(pinf pnorm psub define float @fadd_double_known_negative(float nofpclass(pinf pnorm psub pzero) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_known_negative +; CHECK-LABEL: define nofpclass(pinf pzero psub pnorm) float @fadd_double_known_negative ; CHECK-SAME: (float nofpclass(pinf pzero psub pnorm) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3109,7 +3109,7 @@ define float @fadd_double_known_negative(float nofpclass(pinf pnorm psub pzero) define float @fadd_double_known_negative_non0(float nofpclass(pinf pnorm psub zero) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define nofpclass(nzero) float @fadd_double_known_negative_non0 +; CHECK-LABEL: define nofpclass(pinf zero psub pnorm) float @fadd_double_known_negative_non0 ; CHECK-SAME: (float nofpclass(pinf zero psub pnorm) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3164,7 +3164,7 @@ define float @fadd_double_no_nnorm_nsub(float nofpclass(nnorm nsub) %arg) { define float @fadd_double_no_nopsub_pzero(float nofpclass(psub pzero) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_no_nopsub_pzero +; CHECK-LABEL: define nofpclass(pzero) float @fadd_double_no_nopsub_pzero ; CHECK-SAME: (float nofpclass(pzero psub) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3186,7 +3186,7 @@ define float @fadd_double_no_nonsub_nzero(float nofpclass(nsub nzero) %arg) { define float @fadd_double_no_nopsub_pzero_daz(float nofpclass(psub pzero) %arg) #0 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_no_nopsub_pzero_daz +; CHECK-LABEL: define nofpclass(pzero) float @fadd_double_no_nopsub_pzero_daz ; CHECK-SAME: (float nofpclass(pzero psub) [[ARG:%.*]]) #[[ATTR10]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3197,7 +3197,7 @@ define float @fadd_double_no_nopsub_pzero_daz(float nofpclass(psub pzero) %arg) define float @fadd_double_no_nonsub_nzero_daz(float nofpclass(nsub nzero) %arg) #0 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_no_nonsub_nzero_daz +; CHECK-LABEL: define nofpclass(nzero) float @fadd_double_no_nonsub_nzero_daz ; CHECK-SAME: (float nofpclass(nzero nsub) [[ARG:%.*]]) #[[ATTR10]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3219,7 +3219,7 @@ define float @fadd_double_no_nopsub_pzero_dynamic(float nofpclass(psub pzero) %a define float @fadd_double_no_nonsub_nzero_dynamic(float nofpclass(nsub nzero) %arg) #6 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_no_nonsub_nzero_dynamic +; CHECK-LABEL: define nofpclass(nzero) float @fadd_double_no_nonsub_nzero_dynamic ; CHECK-SAME: (float nofpclass(nzero nsub) [[ARG:%.*]]) #[[ATTR17]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3230,7 +3230,7 @@ define float @fadd_double_no_nonsub_nzero_dynamic(float nofpclass(nsub nzero) %a define float @fadd_double_known_positive_nonsub_ieee(float nofpclass(ninf nnorm sub zero) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define nofpclass(ninf nzero nsub nnorm) float @fadd_double_known_positive_nonsub_ieee +; CHECK-LABEL: define nofpclass(ninf zero nsub nnorm) float @fadd_double_known_positive_nonsub_ieee ; CHECK-SAME: (float nofpclass(ninf zero sub nnorm) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3241,7 +3241,7 @@ define float @fadd_double_known_positive_nonsub_ieee(float nofpclass(ninf nnorm define float @fadd_double_known_positive_nonsub_daz(float nofpclass(ninf nnorm sub zero) %arg) #0 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define nofpclass(ninf nsub nnorm) float @fadd_double_known_positive_nonsub_daz +; CHECK-LABEL: define nofpclass(ninf zero nsub nnorm) float @fadd_double_known_positive_nonsub_daz ; CHECK-SAME: (float nofpclass(ninf zero sub nnorm) [[ARG:%.*]]) #[[ATTR10]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3252,7 +3252,7 @@ define float @fadd_double_known_positive_nonsub_daz(float nofpclass(ninf nnorm s define float @fadd_double_known_positive_nonsub_dynamic(float nofpclass(ninf nnorm sub zero) %arg) #6 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define nofpclass(ninf nsub nnorm) float @fadd_double_known_positive_nonsub_dynamic +; CHECK-LABEL: define nofpclass(ninf zero nsub nnorm) float @fadd_double_known_positive_nonsub_dynamic ; CHECK-SAME: (float nofpclass(ninf zero sub nnorm) [[ARG:%.*]]) #[[ATTR17]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3263,7 +3263,7 @@ define float @fadd_double_known_positive_nonsub_dynamic(float nofpclass(ninf nno define float @fadd_double_known_negative_nonsub_ieee(float nofpclass(pinf pnorm sub zero) %arg) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define nofpclass(nzero) float @fadd_double_known_negative_nonsub_ieee +; CHECK-LABEL: define nofpclass(pinf zero psub pnorm) float @fadd_double_known_negative_nonsub_ieee ; CHECK-SAME: (float nofpclass(pinf zero sub pnorm) [[ARG:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3274,7 +3274,7 @@ define float @fadd_double_known_negative_nonsub_ieee(float nofpclass(pinf pnorm define float @fadd_double_known_negative_nonsub_daz(float nofpclass(pinf pnorm sub zero) %arg) #0 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_known_negative_nonsub_daz +; CHECK-LABEL: define nofpclass(pinf zero psub pnorm) float @fadd_double_known_negative_nonsub_daz ; CHECK-SAME: (float nofpclass(pinf zero sub pnorm) [[ARG:%.*]]) #[[ATTR10]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3285,7 +3285,7 @@ define float @fadd_double_known_negative_nonsub_daz(float nofpclass(pinf pnorm s define float @fadd_double_known_negative_nonsub_dynamic(float nofpclass(pinf pnorm sub zero) %arg) #6 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_double_known_negative_nonsub_dynamic +; CHECK-LABEL: define nofpclass(pinf zero psub pnorm) float @fadd_double_known_negative_nonsub_dynamic ; CHECK-SAME: (float nofpclass(pinf zero sub pnorm) [[ARG:%.*]]) #[[ATTR17]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG]], [[ARG]] ; CHECK-NEXT: ret float [[ADD]] @@ -3351,7 +3351,7 @@ define float @fadd_known_negative_rhs(float %arg0, float nofpclass(pinf psub pno define float @fadd_known_negative(float nofpclass(pinf psub pnorm) %arg0, float nofpclass(pinf psub pnorm) %arg1) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative ; CHECK-SAME: (float nofpclass(pinf psub pnorm) [[ARG0:%.*]], float nofpclass(pinf psub pnorm) [[ARG1:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] @@ -3362,7 +3362,7 @@ define float @fadd_known_negative(float nofpclass(pinf psub pnorm) %arg0, float define float @fadd_known_negative_daz(float nofpclass(pinf psub pnorm) %arg0, float nofpclass(pinf psub pnorm) %arg1) #0 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative_daz +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative_daz ; CHECK-SAME: (float nofpclass(pinf psub pnorm) [[ARG0:%.*]], float nofpclass(pinf psub pnorm) [[ARG1:%.*]]) #[[ATTR10]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] @@ -3373,7 +3373,7 @@ define float @fadd_known_negative_daz(float nofpclass(pinf psub pnorm) %arg0, fl define float @fadd_known_negative_pzero_lhs(float nofpclass(pinf psub pnorm pzero) %arg0, float nofpclass(pinf psub pnorm) %arg1) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative_pzero_lhs +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative_pzero_lhs ; CHECK-SAME: (float nofpclass(pinf pzero psub pnorm) [[ARG0:%.*]], float nofpclass(pinf psub pnorm) [[ARG1:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] @@ -3384,7 +3384,7 @@ define float @fadd_known_negative_pzero_lhs(float nofpclass(pinf psub pnorm pzer define float @fadd_known_negative_pzero_rhs(float nofpclass(pinf psub pnorm) %arg0, float nofpclass(pinf psub pnorm pzero) %arg1) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative_pzero_rhs +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative_pzero_rhs ; CHECK-SAME: (float nofpclass(pinf psub pnorm) [[ARG0:%.*]], float nofpclass(pinf pzero psub pnorm) [[ARG1:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] @@ -3395,7 +3395,7 @@ define float @fadd_known_negative_pzero_rhs(float nofpclass(pinf psub pnorm) %ar define float @fadd_known_negative_pzero(float nofpclass(pinf psub pnorm pzero) %arg0, float nofpclass(pinf psub pnorm pzero) %arg1) { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative_pzero +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative_pzero ; CHECK-SAME: (float nofpclass(pinf pzero psub pnorm) [[ARG0:%.*]], float nofpclass(pinf pzero psub pnorm) [[ARG1:%.*]]) #[[ATTR3]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] @@ -3406,7 +3406,7 @@ define float @fadd_known_negative_pzero(float nofpclass(pinf psub pnorm pzero) % define float @fadd_known_negative_pzero_ftz_daz(float nofpclass(pinf psub pnorm pzero) %arg0, float nofpclass(pinf psub pnorm pzero) %arg1) #0 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative_pzero_ftz_daz +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative_pzero_ftz_daz ; CHECK-SAME: (float nofpclass(pinf pzero psub pnorm) [[ARG0:%.*]], float nofpclass(pinf pzero psub pnorm) [[ARG1:%.*]]) #[[ATTR10]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] @@ -3417,7 +3417,7 @@ define float @fadd_known_negative_pzero_ftz_daz(float nofpclass(pinf psub pnorm define float @fadd_known_negative_pzero_ftz(float nofpclass(pinf psub pnorm pzero) %arg0, float nofpclass(pinf psub pnorm pzero) %arg1) #1 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative_pzero_ftz +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative_pzero_ftz ; CHECK-SAME: (float nofpclass(pinf pzero psub pnorm) [[ARG0:%.*]], float nofpclass(pinf pzero psub pnorm) [[ARG1:%.*]]) #[[ATTR13]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] @@ -3428,7 +3428,7 @@ define float @fadd_known_negative_pzero_ftz(float nofpclass(pinf psub pnorm pzer define float @fadd_known_negative_pzero_daz(float nofpclass(pinf psub pnorm pzero) %arg0, float nofpclass(pinf psub pnorm pzero) %arg1) #2 { ; CHECK: Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) -; CHECK-LABEL: define float @fadd_known_negative_pzero_daz +; CHECK-LABEL: define nofpclass(pinf psub pnorm) float @fadd_known_negative_pzero_daz ; CHECK-SAME: (float nofpclass(pinf pzero psub pnorm) [[ARG0:%.*]], float nofpclass(pinf pzero psub pnorm) [[ARG1:%.*]]) #[[ATTR11]] { ; CHECK-NEXT: [[ADD:%.*]] = fadd float [[ARG0]], [[ARG1]] ; CHECK-NEXT: ret float [[ADD]] `````````` </details> https://github.com/llvm/llvm-project/pull/174123 _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
