llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-llvm-analysis Author: Matt Arsenault (arsenm) <details> <summary>Changes</summary> This is the fdiv version of 5020e0ff1494137ff12b4ed7c8fa896f8088b17b for fmul. --- Full diff: https://github.com/llvm/llvm-project/pull/174652.diff 2 Files Affected: - (modified) llvm/lib/Analysis/ValueTracking.cpp (+14-3) - (modified) llvm/test/Transforms/Attributor/nofpclass-fdiv.ll (+3-3) ``````````diff diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index bdc2e71bdc680..4d5f2e8ac490c 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -5812,8 +5812,9 @@ void computeKnownFPClass(const Value *V, const APInt &DemandedElts, fcNan | fcInf | fcZero | fcNegative, KnownRHS, Q, Depth + 1); - bool KnowSomethingUseful = - KnownRHS.isKnownNeverNaN() || KnownRHS.isKnownNever(fcNegative); + bool KnowSomethingUseful = KnownRHS.isKnownNeverNaN() || + KnownRHS.isKnownNever(fcNegative) || + KnownRHS.isKnownNever(fcPositive); if (KnowSomethingUseful || WantPositive) { const FPClassTest InterestedLHS = @@ -5841,10 +5842,20 @@ void computeKnownFPClass(const Value *V, const APInt &DemandedElts, Known.knownNot(fcNan); } + // xor sign bit. // X / -0.0 is -Inf (or NaN). // +X / +X is +X - if (KnownLHS.isKnownNever(fcNegative) && KnownRHS.isKnownNever(fcNegative)) + if ((KnownLHS.isKnownNever(fcNegative) && + KnownRHS.isKnownNever(fcNegative)) || + (KnownLHS.isKnownNever(fcPositive) && + KnownRHS.isKnownNever(fcPositive))) Known.knownNot(fcNegative); + + if ((KnownLHS.isKnownNever(fcPositive) && + KnownRHS.isKnownNever(fcNegative)) || + (KnownLHS.isKnownNever(fcNegative) && + KnownRHS.isKnownNever(fcPositive))) + Known.knownNot(fcPositive); } else { // Inf REM x and x REM 0 produce NaN. if (KnownLHS.isKnownNeverNaN() && KnownRHS.isKnownNeverNaN() && diff --git a/llvm/test/Transforms/Attributor/nofpclass-fdiv.ll b/llvm/test/Transforms/Attributor/nofpclass-fdiv.ll index 228be4ae748fa..8efed69d9d7c4 100644 --- a/llvm/test/Transforms/Attributor/nofpclass-fdiv.ll +++ b/llvm/test/Transforms/Attributor/nofpclass-fdiv.ll @@ -909,7 +909,7 @@ define float @ret_fdiv_both_signs_positive_or_nan(float %lhs, float %rhs) { ; Result must be positive or nan define float @ret_fdiv_both_signs_negative_or_nan(float %lhs, float %rhs) { -; CHECK-LABEL: define float @ret_fdiv_both_signs_negative_or_nan +; CHECK-LABEL: define nofpclass(ninf nzero nsub nnorm) float @ret_fdiv_both_signs_negative_or_nan ; CHECK-SAME: (float [[LHS:%.*]], float [[RHS:%.*]]) #[[ATTR4]] { ; CHECK-NEXT: [[LHS_FABS:%.*]] = call float @llvm.fabs.f32(float [[LHS]]) #[[ATTR6]] ; CHECK-NEXT: [[RHS_FABS:%.*]] = call float @llvm.fabs.f32(float [[RHS]]) #[[ATTR6]] @@ -928,7 +928,7 @@ define float @ret_fdiv_both_signs_negative_or_nan(float %lhs, float %rhs) { ; Result must be negative or nan define float @ret_fdiv_lhs_negative_rhs_positive(float %lhs, float %rhs) { -; CHECK-LABEL: define float @ret_fdiv_lhs_negative_rhs_positive +; CHECK-LABEL: define nofpclass(pinf pzero psub pnorm) float @ret_fdiv_lhs_negative_rhs_positive ; CHECK-SAME: (float [[LHS:%.*]], float [[RHS:%.*]]) #[[ATTR4]] { ; CHECK-NEXT: [[LHS_FABS:%.*]] = call float @llvm.fabs.f32(float [[LHS]]) #[[ATTR6]] ; CHECK-NEXT: [[RHS_FABS:%.*]] = call float @llvm.fabs.f32(float [[RHS]]) #[[ATTR6]] @@ -945,7 +945,7 @@ define float @ret_fdiv_lhs_negative_rhs_positive(float %lhs, float %rhs) { ; Result must be negative or nan define float @ret_fdiv_rhs_negative_lhs_positive(float %lhs, float %rhs) { -; CHECK-LABEL: define float @ret_fdiv_rhs_negative_lhs_positive +; CHECK-LABEL: define nofpclass(pinf pzero psub pnorm) float @ret_fdiv_rhs_negative_lhs_positive ; CHECK-SAME: (float [[LHS:%.*]], float [[RHS:%.*]]) #[[ATTR4]] { ; CHECK-NEXT: [[LHS_FABS:%.*]] = call float @llvm.fabs.f32(float [[LHS]]) #[[ATTR6]] ; CHECK-NEXT: [[RHS_FABS:%.*]] = call float @llvm.fabs.f32(float [[RHS]]) #[[ATTR6]] `````````` </details> https://github.com/llvm/llvm-project/pull/174652 _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
