Revert of r306525: "Canonicalize clamp of float types to minmax"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306815 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nikolai Bozhenov 2017-06-30 10:39:09 +00:00
parent 940b9a117b
commit fd6c45d107
4 changed files with 31 additions and 130 deletions

View File

@ -195,35 +195,11 @@ struct apint_match {
return false;
}
};
// Either constexpr if or renaming ConstantFP::getValueAPF to
// ConstantFP::getValue is needed to do it via single template
// function for both apint/apfloat.
struct apfloat_match {
const APFloat *&Res;
apfloat_match(const APFloat *&R) : Res(R) {}
template <typename ITy> bool match(ITy *V) {
if (auto *CI = dyn_cast<ConstantFP>(V)) {
Res = &CI->getValueAPF();
return true;
}
if (V->getType()->isVectorTy())
if (const auto *C = dyn_cast<Constant>(V))
if (auto *CI = dyn_cast_or_null<ConstantFP>(C->getSplatValue())) {
Res = &CI->getValueAPF();
return true;
}
return false;
}
};
/// \brief Match a ConstantInt or splatted ConstantVector, binding the
/// specified pointer to the contained APInt.
inline apint_match m_APInt(const APInt *&Res) { return Res; }
/// \brief Match a ConstantFP or splatted ConstantVector, binding the
/// specified pointer to the contained APFloat.
inline apfloat_match m_APFloat(const APFloat *&Res) { return Res; }
template <int64_t Val> struct constantint_match {
template <typename ITy> bool match(ITy *V) {
if (const auto *CI = dyn_cast<ConstantInt>(V)) {

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@ -3933,62 +3933,6 @@ static bool isKnownNonZero(const Value *V) {
return false;
}
/// Match clamp pattern for float types without care about NaNs or signed zeros.
/// Given non-min/max outer cmp/select from the clamp pattern this
/// function recognizes if it can be substitued by a "canonical" min/max
/// pattern.
static SelectPatternResult matchFastFloatClamp(CmpInst::Predicate Pred,
Value *CmpLHS, Value *CmpRHS,
Value *TrueVal, Value *FalseVal,
Value *&LHS, Value *&RHS) {
// Try to match
// X < C1 ? C1 : Min(X, C2) --> Max(C1, Min(X, C2))
// X > C1 ? C1 : Max(X, C2) --> Min(C1, Max(X, C2))
// and return description of the outer Max/Min.
// First, check if select has inverse order:
if (CmpRHS == FalseVal) {
std::swap(TrueVal, FalseVal);
Pred = CmpInst::getInversePredicate(Pred);
}
// Assume success now. If there's no match, callers should not use these anyway.
LHS = TrueVal;
RHS = FalseVal;
const APFloat *FC1;
if (CmpRHS != TrueVal || !match(CmpRHS, m_APFloat(FC1)) || !FC1->isFinite())
return {SPF_UNKNOWN, SPNB_NA, false};
const APFloat *FC2;
switch (Pred) {
case CmpInst::FCMP_OLT:
case CmpInst::FCMP_OLE:
case CmpInst::FCMP_ULT:
case CmpInst::FCMP_ULE:
if (match(FalseVal,
m_CombineOr(m_OrdFMin(m_Specific(CmpLHS), m_APFloat(FC2)),
m_UnordFMin(m_Specific(CmpLHS), m_APFloat(FC2)))) &&
FC1->compare(*FC2) == APFloat::cmpResult::cmpLessThan)
return {SPF_FMAXNUM, SPNB_RETURNS_ANY, false};
break;
case CmpInst::FCMP_OGT:
case CmpInst::FCMP_OGE:
case CmpInst::FCMP_UGT:
case CmpInst::FCMP_UGE:
if (match(FalseVal,
m_CombineOr(m_OrdFMax(m_Specific(CmpLHS), m_APFloat(FC2)),
m_UnordFMax(m_Specific(CmpLHS), m_APFloat(FC2)))) &&
FC1->compare(*FC2) == APFloat::cmpResult::cmpGreaterThan)
return {SPF_FMINNUM, SPNB_RETURNS_ANY, false};
break;
default:
break;
}
return {SPF_UNKNOWN, SPNB_NA, false};
}
/// Match non-obvious integer minimum and maximum sequences.
static SelectPatternResult matchMinMax(CmpInst::Predicate Pred,
Value *CmpLHS, Value *CmpRHS,
@ -4196,18 +4140,7 @@ static SelectPatternResult matchSelectPattern(CmpInst::Predicate Pred,
}
}
if (CmpInst::isIntPredicate(Pred))
return matchMinMax(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal, LHS, RHS);
// According to (IEEE 754-2008 5.3.1), minNum(0.0, -0.0) and similar
// may return either -0.0 or 0.0, so fcmp/select pair has stricter
// semantics than minNum. Be conservative in such case.
if (NaNBehavior != SPNB_RETURNS_ANY ||
(!FMF.noSignedZeros() && !isKnownNonZero(CmpLHS) &&
!isKnownNonZero(CmpRHS)))
return {SPF_UNKNOWN, SPNB_NA, false};
return matchFastFloatClamp(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal, LHS, RHS);
return matchMinMax(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal, LHS, RHS);
}
static Value *lookThroughCast(CmpInst *CmpI, Value *V1, Value *V2,

View File

@ -1374,16 +1374,9 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
auto SPF = SPR.Flavor;
if (SelectPatternResult::isMinOrMax(SPF)) {
// Canonicalize so that
// - type casts are outside select patterns.
// - float clamp is transformed to min/max pattern
Value *CmpLHS = cast<CmpInst>(CondVal)->getOperand(0);
Value *CmpRHS = cast<CmpInst>(CondVal)->getOperand(1);
if ((LHS->getType()->getPrimitiveSizeInBits() !=
SelType->getPrimitiveSizeInBits()) ||
(LHS->getType()->isFPOrFPVectorTy() &&
((CmpLHS != LHS && CmpLHS != RHS) ||
(CmpRHS != LHS && CmpRHS != RHS)))) {
// Canonicalize so that type casts are outside select patterns.
if (LHS->getType()->getPrimitiveSizeInBits() !=
SelType->getPrimitiveSizeInBits()) {
CmpInst::Predicate Pred = getCmpPredicateForMinMax(SPF, SPR.Ordered);
Value *Cmp;

View File

@ -7,9 +7,9 @@ define float @clamp_float_fast_ordered_strict_maxmin(float %x) {
; CHECK-LABEL: @clamp_float_fast_ordered_strict_maxmin(
; CHECK-NEXT: [[CMP2:%.*]] = fcmp fast olt float [[X:%.*]], 2.550000e+02
; CHECK-NEXT: [[MIN:%.*]] = select i1 [[CMP2]], float [[X]], float 2.550000e+02
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast oge float [[MIN]], 1.000000e+00
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MIN]], float 1.000000e+00
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast olt float [[X]], 1.000000e+00
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 1.000000e+00, float [[MIN]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast olt float %x, 255.0
%min = select i1 %cmp2, float %x, float 255.0
@ -24,9 +24,9 @@ define float @clamp_float_fast_ordered_nonstrict_maxmin(float %x) {
; CHECK-LABEL: @clamp_float_fast_ordered_nonstrict_maxmin(
; CHECK-NEXT: [[CMP2:%.*]] = fcmp fast olt float [[X:%.*]], 2.550000e+02
; CHECK-NEXT: [[MIN:%.*]] = select i1 [[CMP2]], float [[X]], float 2.550000e+02
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast oge float [[MIN]], 1.000000e+00
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MIN]], float 1.000000e+00
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast ole float [[X]], 1.000000e+00
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 1.000000e+00, float [[MIN]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast olt float %x, 255.0
%min = select i1 %cmp2, float %x, float 255.0
@ -41,9 +41,9 @@ define float @clamp_float_fast_ordered_strict_minmax(float %x) {
; CHECK-LABEL: @clamp_float_fast_ordered_strict_minmax(
; CHECK-NEXT: [[CMP2:%.*]] = fcmp fast ogt float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[MAX:%.*]] = select i1 [[CMP2]], float [[X]], float 1.000000e+00
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast ole float [[MAX]], 2.550000e+02
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MAX]], float 2.550000e+02
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast ogt float [[X]], 2.550000e+02
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 2.550000e+02, float [[MAX]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast ogt float %x, 1.0
%max = select i1 %cmp2, float %x, float 1.0
@ -58,9 +58,9 @@ define float @clamp_float_fast_ordered_nonstrict_minmax(float %x) {
; CHECK-LABEL: @clamp_float_fast_ordered_nonstrict_minmax(
; CHECK-NEXT: [[CMP2:%.*]] = fcmp fast ogt float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[MAX:%.*]] = select i1 [[CMP2]], float [[X]], float 1.000000e+00
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast ole float [[MAX]], 2.550000e+02
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MAX]], float 2.550000e+02
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast oge float [[X]], 2.550000e+02
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 2.550000e+02, float [[MAX]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast ogt float %x, 1.0
%max = select i1 %cmp2, float %x, float 1.0
@ -78,9 +78,9 @@ define float @clamp_float_fast_unordered_strict_maxmin(float %x) {
; CHECK-LABEL: @clamp_float_fast_unordered_strict_maxmin(
; CHECK-NEXT: [[CMP2_INV:%.*]] = fcmp fast oge float [[X:%.*]], 2.550000e+02
; CHECK-NEXT: [[MIN:%.*]] = select i1 [[CMP2_INV]], float 2.550000e+02, float [[X]]
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast oge float [[MIN]], 1.000000e+00
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MIN]], float 1.000000e+00
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast ult float [[X]], 1.000000e+00
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 1.000000e+00, float [[MIN]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast ult float %x, 255.0
%min = select i1 %cmp2, float %x, float 255.0
@ -95,9 +95,9 @@ define float @clamp_float_fast_unordered_nonstrict_maxmin(float %x) {
; CHECK-LABEL: @clamp_float_fast_unordered_nonstrict_maxmin(
; CHECK-NEXT: [[CMP2_INV:%.*]] = fcmp fast oge float [[X:%.*]], 2.550000e+02
; CHECK-NEXT: [[MIN:%.*]] = select i1 [[CMP2_INV]], float 2.550000e+02, float [[X]]
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast oge float [[MIN]], 1.000000e+00
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MIN]], float 1.000000e+00
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast ule float [[X]], 1.000000e+00
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 1.000000e+00, float [[MIN]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast ult float %x, 255.0
%min = select i1 %cmp2, float %x, float 255.0
@ -112,9 +112,9 @@ define float @clamp_float_fast_unordered_strict_minmax(float %x) {
; CHECK-LABEL: @clamp_float_fast_unordered_strict_minmax(
; CHECK-NEXT: [[CMP2_INV:%.*]] = fcmp fast ole float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[MAX:%.*]] = select i1 [[CMP2_INV]], float 1.000000e+00, float [[X]]
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast ole float [[MAX]], 2.550000e+02
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MAX]], float 2.550000e+02
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast ugt float [[X]], 2.550000e+02
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 2.550000e+02, float [[MAX]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast ugt float %x, 1.0
%max = select i1 %cmp2, float %x, float 1.0
@ -129,9 +129,9 @@ define float @clamp_float_fast_unordered_nonstrict_minmax(float %x) {
; CHECK-LABEL: @clamp_float_fast_unordered_nonstrict_minmax(
; CHECK-NEXT: [[CMP2_INV:%.*]] = fcmp fast ole float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[MAX:%.*]] = select i1 [[CMP2_INV]], float 1.000000e+00, float [[X]]
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast ole float [[MAX]], 2.550000e+02
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[MAX]], float 2.550000e+02
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[CMP1:%.*]] = fcmp fast uge float [[X]], 2.550000e+02
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP1]], float 2.550000e+02, float [[MAX]]
; CHECK-NEXT: ret float [[R]]
;
%cmp2 = fcmp fast ugt float %x, 1.0
%max = select i1 %cmp2, float %x, float 1.0
@ -143,14 +143,13 @@ define float @clamp_float_fast_unordered_nonstrict_minmax(float %x) {
; Some more checks with fast
; (X > 1.0) ? min(x, 255.0) : 1.0
; That did not match because select was in inverse order.
define float @clamp_test_1(float %x) {
; CHECK-LABEL: @clamp_test_1(
; CHECK-NEXT: [[INNER_CMP_INV:%.*]] = fcmp fast oge float [[X:%.*]], 2.550000e+02
; CHECK-NEXT: [[INNER_SEL:%.*]] = select i1 [[INNER_CMP_INV]], float 2.550000e+02, float [[X]]
; CHECK-NEXT: [[DOTINV:%.*]] = fcmp fast oge float [[INNER_SEL]], 1.000000e+00
; CHECK-NEXT: [[R1:%.*]] = select i1 [[DOTINV]], float [[INNER_SEL]], float 1.000000e+00
; CHECK-NEXT: ret float [[R1]]
; CHECK-NEXT: [[OUTER_CMP:%.*]] = fcmp fast ugt float [[X]], 1.000000e+00
; CHECK-NEXT: [[R:%.*]] = select i1 [[OUTER_CMP]], float [[INNER_SEL]], float 1.000000e+00
; CHECK-NEXT: ret float [[R]]
;
%inner_cmp = fcmp fast ult float %x, 255.0
%inner_sel = select i1 %inner_cmp, float %x, float 255.0