[InstCombine] choose 1 form of abs and nabs as canonical

[spatel]

Summary

We already do this for min/max (see the blob above the diff), so we should do the same for abs/nabs.
Compare with 0 and having the original argument as the true value of the select feels the most natural to me, but if someone prefers a different flavor, we could do that too.

This might solve the motivating cases for D47037 and D47041, but I think those patches still make sense. We can't guarantee this canonicalization if the icmp has more than one use.

I adjusted the shifty abs transform to the pattern here to make that transform more efficient.

[spatel]

Patch updated:
No code changes, but I forgot to update test comments that would become stale.

[efriedma]

I guess it doesn't really matter what form you choose as canonical, given the backend will pattern-match it anyway, but "x > 0" seems like a weird choice; it can't be lowered to a sign-bit check like "x < 0".

[spatel]

In D47076#1104961, @efriedma wrote:

I guess it doesn't really matter what form you choose as canonical, given the backend will pattern-match it anyway, but "x > 0" seems like a weird choice; it can't be lowered to a sign-bit check like "x < 0".

Good point. It should make the code simpler if we always choose <0 too. Let me update.

[spatel]

Patch updated:
Always choose "<s 0" because a sign-bit check and zero constant are most likely to match what codegen prefers.

[efriedma]

LGTM

lib/Transforms/InstCombine/InstCombineAndOrXor.cpp

Instruction *InstCombiner::visitXor(BinaryOperator &I) {
 
   const APInt *ShAmt;
   Type *Ty = I.getType();
   if (match(Op1, m_AShr(m_Value(A), m_APInt(ShAmt))) &&
       Op1->hasNUses(2) && *ShAmt == Ty->getScalarSizeInBits() - 1 &&
       match(Op0, m_OneUse(m_c_Add(m_Specific(A), m_Specific(Op1))))) {
     // B = ashr i32 A, 31 ; smear the sign bit
     // xor (add A, B), B  ; add -1 and flip bits if negative
-    // --> (A < 0) ? -A : A
-    Value *Cmp = Builder.CreateICmpSLT(A, ConstantInt::getNullValue(Ty));
+    // --> (A > 0) ? A : -A
+    Value *Cmp = Builder.CreateICmpSGT(A, ConstantInt::getNullValue(Ty));
     // Copy the nuw/nsw flags from the add to the negate.
     auto *Add = cast<BinaryOperator>(Op0);
     Value *Neg = Builder.CreateNeg(A, "", Add->hasNoUnsignedWrap(),
                                    Add->hasNoSignedWrap());
-    return SelectInst::Create(Cmp, Neg, A);
+    return SelectInst::Create(Cmp, A, Neg);
   }
 
   // Eliminate a bitwise 'not' op of 'not' min/max by inverting the min/max:
   //
   //   %notx = xor i32 %x, -1
   //   %cmp1 = icmp sgt i32 %notx, %y
   //   %smax = select i1 %cmp1, i32 %notx, i32 %y
   //   %res = xor i32 %smax, -1

lib/Transforms/InstCombine/InstCombineSelect.cpp

canonicalizeMinMaxWithConstant(SelectInst &Sel, ICmpInst &Cmp,
   assert(Sel.getTrueValue() == RHS && Sel.getFalseValue() == LHS &&
          "Unexpected results from matchSelectPattern");
   Sel.setTrueValue(LHS);
   Sel.setFalseValue(RHS);
   Sel.swapProfMetadata();
   return &Sel;
 }
 
+/// There are 4 select variants for each of ABS/NABS (different compare
+/// constants, compare predicates, select operands). Canonicalize to 1 pattern.
+/// This makes CSE more likely and compare-with-0 is generally good for codegen.
+static Instruction *canonicalizeAbsNabs(SelectInst &Sel, ICmpInst &Cmp,
+                                        InstCombiner::BuilderTy &Builder) {
+  if (!Cmp.hasOneUse() || !isa<Constant>(Cmp.getOperand(1)))
+    return nullptr;
+
+  // Canonicalize the compare predicate based on whether we have abs or nabs.
+  // ABS:  (X >s 0) ? X : -X
+  // NABS: (X <s 0) ? X : -X
+  Value *LHS, *RHS;
+  SelectPatternResult SPR = matchSelectPattern(&Sel, LHS, RHS);
+  ICmpInst::Predicate CanonicalPred;
+  if (SPR.Flavor == SelectPatternFlavor::SPF_ABS)
+    CanonicalPred = ICmpInst::ICMP_SGT;
+  else if (SPR.Flavor == SelectPatternFlavor::SPF_NABS)
+    CanonicalPred = ICmpInst::ICMP_SLT;
+  else
+    return nullptr;
+
+  // Is this already canonical?
+  if (match(Cmp.getOperand(1), m_ZeroInt()) &&
+      Cmp.getPredicate() == CanonicalPred)
+    return nullptr;
+
+  // Create the canonical compare.
+  Cmp.setPredicate(CanonicalPred);
+  Cmp.setOperand(1, ConstantInt::getNullValue(LHS->getType()));
+
+  // If the select operands do not change, we're done.
+  Value *TVal = Sel.getTrueValue();
+  Value *FVal = Sel.getFalseValue();
+  if (TVal == LHS && match(FVal, m_Neg(m_Specific(TVal))))
+    return &Sel;
+
+  // If we are swapping the select operands, swap the metadata too.
+  assert(FVal == LHS && match(TVal, m_Neg(m_Specific(FVal))) &&
+         "Unexpected results from matchSelectPattern");
+  Sel.setTrueValue(FVal);
+  Sel.setFalseValue(TVal);
+  Sel.swapProfMetadata();
+  return &Sel;
+}
+
 /// Visit a SelectInst that has an ICmpInst as its first operand.
 Instruction *InstCombiner::foldSelectInstWithICmp(SelectInst &SI,
                                                   ICmpInst *ICI) {
   Value *TrueVal = SI.getTrueValue();
   Value *FalseVal = SI.getFalseValue();
 
   if (Instruction *NewSel = canonicalizeMinMaxWithConstant(SI, *ICI, Builder))
     return NewSel;
 
+  if (Instruction *NewAbs = canonicalizeAbsNabs(SI, *ICI, Builder))
+    return NewAbs;
+
   bool Changed = adjustMinMax(SI, *ICI);
 
   if (Value *V = foldSelectICmpAnd(SI, ICI, Builder))
     return replaceInstUsesWith(SI, V);
 
   // NOTE: if we wanted to, this is where to detect integer MIN/MAX
   ICmpInst::Predicate Pred = ICI->getPredicate();
   Value *CmpLHS = ICI->getOperand(0);

test/Transforms/InstCombine/abs-1.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt < %s -instcombine -S | FileCheck %s
 
 target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
 
 declare i32 @abs(i32)
 declare i64 @labs(i64)
 declare i64 @llabs(i64)
 
 ; Test that the abs library call simplifier works correctly.
 ; abs(x) -> x >s -1 ? x : -x.
 
 define i32 @test_abs(i32 %x) {
 ; CHECK-LABEL: @test_abs(
-; CHECK-NEXT:    [[ISPOS:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[ISPOS:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[NEG:%.*]] = sub i32 0, [[X]]
 ; CHECK-NEXT:    [[TMP1:%.*]] = select i1 [[ISPOS]], i32 [[X]], i32 [[NEG]]
 ; CHECK-NEXT:    ret i32 [[TMP1]]
 ;
   %ret = call i32 @abs(i32 %x)
   ret i32 %ret
 }
 
 define i64 @test_labs(i64 %x) {
 ; CHECK-LABEL: @test_labs(
-; CHECK-NEXT:    [[ISPOS:%.*]] = icmp sgt i64 [[X:%.*]], -1
+; CHECK-NEXT:    [[ISPOS:%.*]] = icmp sgt i64 [[X:%.*]], 0
 ; CHECK-NEXT:    [[NEG:%.*]] = sub i64 0, [[X]]
 ; CHECK-NEXT:    [[TMP1:%.*]] = select i1 [[ISPOS]], i64 [[X]], i64 [[NEG]]
 ; CHECK-NEXT:    ret i64 [[TMP1]]
 ;
   %ret = call i64 @labs(i64 %x)
   ret i64 %ret
 }
 
 define i64 @test_llabs(i64 %x) {
 ; CHECK-LABEL: @test_llabs(
-; CHECK-NEXT:    [[ISPOS:%.*]] = icmp sgt i64 [[X:%.*]], -1
+; CHECK-NEXT:    [[ISPOS:%.*]] = icmp sgt i64 [[X:%.*]], 0
 ; CHECK-NEXT:    [[NEG:%.*]] = sub i64 0, [[X]]
 ; CHECK-NEXT:    [[TMP1:%.*]] = select i1 [[ISPOS]], i64 [[X]], i64 [[NEG]]
 ; CHECK-NEXT:    ret i64 [[TMP1]]
 ;
   %ret = call i64 @llabs(i64 %x)
   ret i64 %ret
 }
 
;
   %abs = select i1 %cmp, i8 %x, i8 %neg
   ret i8 %abs
 }
 
 ; FIXME: Vectors should work too.
 
 define <2 x i8> @abs_canonical_2(<2 x i8> %x) {
 ; CHECK-LABEL: @abs_canonical_2(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i8> [[X:%.*]], <i8 -1, i8 -1>
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i8> [[X:%.*]], zeroinitializer
 ; CHECK-NEXT:    [[NEG:%.*]] = sub <2 x i8> zeroinitializer, [[X]]
 ; CHECK-NEXT:    [[ABS:%.*]] = select <2 x i1> [[CMP]], <2 x i8> [[X]], <2 x i8> [[NEG]]
 ; CHECK-NEXT:    ret <2 x i8> [[ABS]]
 ;
   %cmp = icmp sgt <2 x i8> %x, <i8 -1, i8 -1>
   %neg = sub <2 x i8> zeroinitializer, %x
   %abs = select <2 x i1> %cmp, <2 x i8> %x, <2 x i8> %neg
   ret <2 x i8> %abs
 }
 
 ; NSW should not change.
 
 define i8 @abs_canonical_3(i8 %x) {
 ; CHECK-LABEL: @abs_canonical_3(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[X:%.*]], 0
 ; CHECK-NEXT:    [[NEG:%.*]] = sub nsw i8 0, [[X]]
-; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP]], i8 [[NEG]], i8 [[X]]
+; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP]], i8 [[X]], i8 [[NEG]]
 ; CHECK-NEXT:    ret i8 [[ABS]]
 ;
   %cmp = icmp slt i8 %x, 0
   %neg = sub nsw i8 0, %x
   %abs = select i1 %cmp, i8 %neg, i8 %x
   ret i8 %abs
 }
 
 define i8 @abs_canonical_4(i8 %x) {
 ; CHECK-LABEL: @abs_canonical_4(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[X:%.*]], 0
 ; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X]]
-; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP]], i8 [[NEG]], i8 [[X]]
+; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP]], i8 [[X]], i8 [[NEG]]
 ; CHECK-NEXT:    ret i8 [[ABS]]
 ;
   %cmp = icmp slt i8 %x, 1
   %neg = sub i8 0, %x
   %abs = select i1 %cmp, i8 %neg, i8 %x
   ret i8 %abs
 }
 
 ; FIXME: We should have a canonical form of nabs to make CSE easier.
 
 define i8 @nabs_canonical_1(i8 %x) {
 ; CHECK-LABEL: @nabs_canonical_1(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0
 ; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X]]
-; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP]], i8 [[NEG]], i8 [[X]]
+; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP]], i8 [[X]], i8 [[NEG]]
 ; CHECK-NEXT:    ret i8 [[ABS]]
 ;
   %cmp = icmp sgt i8 %x, 0
   %neg = sub i8 0, %x
   %abs = select i1 %cmp, i8 %neg, i8 %x
   ret i8 %abs
 }
 
 ; FIXME: Vectors should work too.
 
 define <2 x i8> @nabs_canonical_2(<2 x i8> %x) {
 ; CHECK-LABEL: @nabs_canonical_2(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i8> [[X:%.*]], <i8 -1, i8 -1>
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt <2 x i8> [[X:%.*]], zeroinitializer
 ; CHECK-NEXT:    [[NEG:%.*]] = sub <2 x i8> zeroinitializer, [[X]]
-; CHECK-NEXT:    [[ABS:%.*]] = select <2 x i1> [[CMP]], <2 x i8> [[NEG]], <2 x i8> [[X]]
+; CHECK-NEXT:    [[ABS:%.*]] = select <2 x i1> [[CMP]], <2 x i8> [[X]], <2 x i8> [[NEG]]
 ; CHECK-NEXT:    ret <2 x i8> [[ABS]]
 ;
   %cmp = icmp sgt <2 x i8> %x, <i8 -1, i8 -1>
   %neg = sub <2 x i8> zeroinitializer, %x
   %abs = select <2 x i1> %cmp, <2 x i8> %neg, <2 x i8> %x
   ret <2 x i8> %abs
 }
 
;
   %cmp = icmp slt i8 %x, 0
   %neg = sub nsw i8 0, %x
   %abs = select i1 %cmp, i8 %x, i8 %neg
   ret i8 %abs
 }
 
 define i8 @nabs_canonical_4(i8 %x) {
 ; CHECK-LABEL: @nabs_canonical_4(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0
 ; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X]]
 ; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP]], i8 [[X]], i8 [[NEG]]
 ; CHECK-NEXT:    ret i8 [[ABS]]
 ;
   %cmp = icmp slt i8 %x, 1
   %neg = sub i8 0, %x
   %abs = select i1 %cmp, i8 %x, i8 %neg
   ret i8 %abs
 }
 
 ; The following 5 tests use a shift+add+xor to implement abs():
 ; B = ashr i8 A, 7  -- smear the sign bit.
 ; xor (add A, B), B -- add -1 and flip bits if negative
 
 define i8 @shifty_abs_commute0(i8 %x) {
 ; CHECK-LABEL: @shifty_abs_commute0(
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp slt i8 [[X:%.*]], 0
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp sgt i8 [[X:%.*]], 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = sub i8 0, [[X]]
-; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[TMP1]], i8 [[TMP2]], i8 [[X]]
+; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[TMP1]], i8 [[X]], i8 [[TMP2]]
 ; CHECK-NEXT:    ret i8 [[ABS]]
 ;
   %signbit = ashr i8 %x, 7
   %add = add i8 %signbit, %x
   %abs = xor i8 %add, %signbit
   ret i8 %abs
 }
 
 define i8 @shifty_abs_commute0_nsw(i8 %x) {
 ; CHECK-LABEL: @shifty_abs_commute0_nsw(
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp slt i8 [[X:%.*]], 0
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp sgt i8 [[X:%.*]], 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = sub nsw i8 0, [[X]]
-; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[TMP1]], i8 [[TMP2]], i8 [[X]]
+; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[TMP1]], i8 [[X]], i8 [[TMP2]]
 ; CHECK-NEXT:    ret i8 [[ABS]]
 ;
   %signbit = ashr i8 %x, 7
   %add = add nsw i8 %signbit, %x
   %abs = xor i8 %add, %signbit
   ret i8 %abs
 }
 
;
   %signbit = ashr i8 %x, 7
   %add = add nuw i8 %signbit, %x
   %abs = xor i8 %add, %signbit
   ret i8 %abs
 }
 
 define <2 x i8> @shifty_abs_commute1(<2 x i8> %x) {
 ; CHECK-LABEL: @shifty_abs_commute1(
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp slt <2 x i8> [[X:%.*]], zeroinitializer
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp sgt <2 x i8> [[X:%.*]], zeroinitializer
 ; CHECK-NEXT:    [[TMP2:%.*]] = sub <2 x i8> zeroinitializer, [[X]]
-; CHECK-NEXT:    [[ABS:%.*]] = select <2 x i1> [[TMP1]], <2 x i8> [[TMP2]], <2 x i8> [[X]]
+; CHECK-NEXT:    [[ABS:%.*]] = select <2 x i1> [[TMP1]], <2 x i8> [[X]], <2 x i8> [[TMP2]]
 ; CHECK-NEXT:    ret <2 x i8> [[ABS]]
 ;
   %signbit = ashr <2 x i8> %x, <i8 7, i8 7>
   %add = add <2 x i8> %signbit, %x
   %abs = xor <2 x i8> %signbit, %add
   ret <2 x i8> %abs
 }
 
 define <2 x i8> @shifty_abs_commute2(<2 x i8> %x) {
 ; CHECK-LABEL: @shifty_abs_commute2(
 ; CHECK-NEXT:    [[Y:%.*]] = mul <2 x i8> [[X:%.*]], <i8 3, i8 3>
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp slt <2 x i8> [[Y]], zeroinitializer
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp sgt <2 x i8> [[Y]], zeroinitializer
 ; CHECK-NEXT:    [[TMP2:%.*]] = sub <2 x i8> zeroinitializer, [[Y]]
-; CHECK-NEXT:    [[ABS:%.*]] = select <2 x i1> [[TMP1]], <2 x i8> [[TMP2]], <2 x i8> [[Y]]
+; CHECK-NEXT:    [[ABS:%.*]] = select <2 x i1> [[TMP1]], <2 x i8> [[Y]], <2 x i8> [[TMP2]]
 ; CHECK-NEXT:    ret <2 x i8> [[ABS]]
 ;
   %y = mul <2 x i8> %x, <i8 3, i8 3>   ; extra op to thwart complexity-based canonicalization
   %signbit = ashr <2 x i8> %y, <i8 7, i8 7>
   %add = add <2 x i8> %y, %signbit
   %abs = xor <2 x i8> %signbit, %add
   ret <2 x i8> %abs
 }
 
 define i8 @shifty_abs_commute3(i8 %x) {
 ; CHECK-LABEL: @shifty_abs_commute3(
 ; CHECK-NEXT:    [[Y:%.*]] = mul i8 [[X:%.*]], 3
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp slt i8 [[Y]], 0
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp sgt i8 [[Y]], 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = sub i8 0, [[Y]]
-; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[TMP1]], i8 [[TMP2]], i8 [[Y]]
+; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[TMP1]], i8 [[Y]], i8 [[TMP2]]
 ; CHECK-NEXT:    ret i8 [[ABS]]
 ;
   %y = mul i8 %x, 3                    ; extra op to thwart complexity-based canonicalization
   %signbit = ashr i8 %y, 7
   %add = add i8 %y, %signbit
   %abs = xor i8 %add, %signbit
   ret i8 %abs
 }

test/Transforms/InstCombine/abs_abs.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt < %s -instcombine -S | FileCheck %s
 
 define i32 @abs_abs_x01(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x01(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define <2 x i32> @abs_abs_x01_vec(<2 x i32> %x) {
 ; CHECK-LABEL: @abs_abs_x01_vec(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i32> [[X:%.*]], <i32 -1, i32 -1>
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i32> [[X:%.*]], zeroinitializer
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw <2 x i32> zeroinitializer, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select <2 x i1> [[CMP]], <2 x i32> [[X]], <2 x i32> [[SUB]]
 ; CHECK-NEXT:    ret <2 x i32> [[COND]]
 ;
   %cmp = icmp sgt <2 x i32> %x, <i32 -1, i32 -1>
   %sub = sub nsw <2 x i32> zeroinitializer, %x
   %cond = select <2 x i1> %cmp, <2 x i32> %x, <2 x i32> %sub
   %cmp1 = icmp sgt <2 x i32> %cond, <i32 -1, i32 -1>
;
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x03(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x03(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x04(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x04(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define <2 x i32> @abs_abs_x04_vec(<2 x i32> %x) {
 ; CHECK-LABEL: @abs_abs_x04_vec(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt <2 x i32> [[X:%.*]], <i32 1, i32 1>
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i32> [[X:%.*]], zeroinitializer
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw <2 x i32> zeroinitializer, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select <2 x i1> [[CMP]], <2 x i32> [[SUB]], <2 x i32> [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select <2 x i1> [[CMP]], <2 x i32> [[X]], <2 x i32> [[SUB]]
 ; CHECK-NEXT:    ret <2 x i32> [[COND]]
 ;
   %cmp = icmp slt <2 x i32> %x, <i32 1, i32 1>
   %sub = sub nsw <2 x i32> zeroinitializer, %x
   %cond = select <2 x i1> %cmp, <2 x i32> %sub, <2 x i32> %x
   %cmp1 = icmp sgt <2 x i32> %cond, <i32 -1, i32 -1>
   %sub16 = sub nsw <2 x i32> zeroinitializer, %cond
   %cond18 = select <2 x i1> %cmp1, <2 x i32> %cond, <2 x i32> %sub16
   ret <2 x i32> %cond18
 }
 
 define i32 @abs_abs_x05(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x05(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, 0
;
   %cmp1 = icmp sgt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x07(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x07(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x08(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x08(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x09(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x09(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 0
;
   %cmp1 = icmp slt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x11(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x11(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x12(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x12(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x13(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x13(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 1
;
   %cmp1 = icmp slt i32 %cond, 1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x15(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x15(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_abs_x16(i32 %x) {
 ; CHECK-LABEL: @abs_abs_x16(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x01(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x01(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x02(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x02(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
;
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x04(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x04(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x05(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x05(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x06(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x06(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
;
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x08(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x08(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x09(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x09(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x10(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x10(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
;
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x12(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x12(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x13(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x13(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x14(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x14(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
;
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_nabs_x16(i32 %x) {
 ; CHECK-LABEL: @nabs_nabs_x16(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x01(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x01(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, -1
;
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x03(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x03(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x04(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x04(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x05(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x05(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, 0
;
   %cmp1 = icmp sgt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x07(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x07(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x08(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x08(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x09(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x09(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 0
;
   %cmp1 = icmp slt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x11(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x11(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x12(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x12(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x13(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x13(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 1
;
   %cmp1 = icmp slt i32 %cond, 1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x15(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x15(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @abs_nabs_x16(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x16(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x01(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x01(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x02(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x02(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
;
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x04(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x04(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, -1
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x05(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x05(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x06(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x06(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
;
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x08(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x08(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp sgt i32 %cond, 0
   %sub9 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %sub9, i32 %cond
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x09(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x09(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x10(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x10(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
;
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x12(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x12(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 0
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x13(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x13(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x14(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x14(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
-; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[SUB]], i32 [[X]]
+; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, 0
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %x, i32 %sub
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
;
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 
 define i32 @nabs_abs_x16(i32 %x) {
 ; CHECK-LABEL: @nabs_abs_x16(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, [[X]]
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp slt i32 %x, 1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x
   %cmp1 = icmp slt i32 %cond, 1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16
   ret i32 %cond18
 }
 

test/Transforms/InstCombine/icmp.ll

;
   ret <2 x i1> %v
 }
 
 define i32 @f5(i8 %a, i8 %b) {
 ; CHECK-LABEL: @f5(
 ; CHECK-NEXT:    [[CONV:%.*]] = zext i8 %a to i32
 ; CHECK-NEXT:    [[CONV3:%.*]] = zext i8 %b to i32
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 [[CONV]], [[CONV3]]
-; CHECK-NEXT:    [[CMP4:%.*]] = icmp slt i32 [[SUB]], 0
+; CHECK-NEXT:    [[CMP4:%.*]] = icmp sgt i32 [[SUB]], 0
 ; CHECK-NEXT:    [[SUB7:%.*]] = sub nsw i32 0, [[SUB]]
-; CHECK-NEXT:    [[SUB7_SUB:%.*]] = select i1 [[CMP4]], i32 [[SUB7]], i32 [[SUB]]
+; CHECK-NEXT:    [[SUB7_SUB:%.*]] = select i1 [[CMP4]], i32 [[SUB]], i32 [[SUB7]]
 ; CHECK-NEXT:    ret i32 [[SUB7_SUB]]
 ;
   %conv = zext i8 %a to i32
   %conv3 = zext i8 %b to i32
   %sub = sub nsw i32 %conv, %conv3
   %cmp4 = icmp slt i32 %sub, 0
   %sub7 = sub nsw i32 0, %sub
   %sub7.sub = select i1 %cmp4, i32 %sub7, i32 %sub
;
   %c = icmp sgt i8 %b2, %a2
   ret i1 %c
 }
 
 ; Make sure InstCombine doesn't try too hard to simplify the icmp and break the abs idiom
 define i32 @abs_preserve(i32 %x) {
 ; CHECK-LABEL: @abs_preserve(
 ; CHECK-NEXT:    [[A:%.*]] = shl nsw i32 [[X:%.*]], 1
-; CHECK-NEXT:    [[C:%.*]] = icmp sgt i32 [[A]], -1
+; CHECK-NEXT:    [[C:%.*]] = icmp sgt i32 [[A]], 0
 ; CHECK-NEXT:    [[NEGA:%.*]] = sub i32 0, [[A]]
 ; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[C]], i32 [[A]], i32 [[NEGA]]
 ; CHECK-NEXT:    ret i32 [[ABS]]
 ;
   %a = mul nsw i32 %x, 2
   %c = icmp sge i32 %a, 0
   %nega = sub i32 0, %a
   %abs = select i1 %c, i32 %a, i32 %nega

test/Transforms/InstCombine/max-of-nots.ll

 
  ; negative test case (i.e. can not simplify) : ABS(MIN(NOT x,y))
 define i32 @abs_of_min_of_not(i32 %x, i32 %y) {
 ; CHECK-LABEL: @abs_of_min_of_not(
 ; CHECK-NEXT:    [[XORD:%.*]] = xor i32 [[X:%.*]], -1
 ; CHECK-NEXT:    [[YADD:%.*]] = add i32 [[Y:%.*]], 2
 ; CHECK-NEXT:    [[COND_I:%.*]] = icmp slt i32 [[YADD]], [[XORD]]
 ; CHECK-NEXT:    [[MIN:%.*]] = select i1 [[COND_I]], i32 [[YADD]], i32 [[XORD]]
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[MIN]], -1
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[MIN]], 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub i32 0, [[MIN]]
 ; CHECK-NEXT:    [[ABS:%.*]] = select i1 [[CMP2]], i32 [[MIN]], i32 [[SUB]]
 ; CHECK-NEXT:    ret i32 [[ABS]]
 ;
 
   %xord = xor i32 %x, -1
   %yadd = add i32 %y, 2
   %cond.i = icmp sge i32 %yadd, %xord

test/Transforms/InstCombine/select_meta.ll

;
   %1 = icmp slt i32 %a, -32768
   %2 = trunc i32 %a to i16
   %3 = select i1 %1, i16 %2, i16 -32768, !prof !1
   ret i16 %3
 }
 
 define i32 @abs_nabs_x01(i32 %x) {
 ; CHECK-LABEL: @abs_nabs_x01(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 %x, -1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 %x, 0
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw i32 0, %x
 ; CHECK-NEXT:    [[COND1:%.*]] = select i1 [[CMP]], i32 %x, i32 [[SUB]], !prof ![[$MD1]]
 ; CHECK-NEXT:    ret i32 [[COND1]]
 ;
   %cmp = icmp sgt i32 %x, -1
   %sub = sub nsw i32 0, %x
   %cond = select i1 %cmp, i32 %sub, i32 %x, !prof !1
   %cmp1 = icmp sgt i32 %cond, -1
   %sub16 = sub nsw i32 0, %cond
   %cond18 = select i1 %cmp1, i32 %cond, i32 %sub16, !prof !2
   ret i32 %cond18
 }
 
 define <2 x i32> @abs_nabs_x01_vec(<2 x i32> %x) {
 ; CHECK-LABEL: @abs_nabs_x01_vec(
-; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i32> %x, <i32 -1, i32 -1>
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i32> %x, zeroinitializer
 ; CHECK-NEXT:    [[SUB:%.*]] = sub nsw <2 x i32> zeroinitializer, %x
 ; CHECK-NEXT:    [[COND1:%.*]] = select <2 x i1> [[CMP]], <2 x i32> %x, <2 x i32> [[SUB]], !prof ![[$MD1]]
 ; CHECK-NEXT:    ret <2 x i32> [[COND1]]
 ;
   %cmp = icmp sgt <2 x i32> %x, <i32 -1, i32 -1>
   %sub = sub nsw <2 x i32> zeroinitializer, %x
   %cond = select <2 x i1> %cmp, <2 x i32> %sub, <2 x i32> %x, !prof !1
   %cmp1 = icmp sgt <2 x i32> %cond, <i32 -1, i32 -1>

test/Transforms/InstSimplify/call-callconv.ll

 ; RUN: opt < %s -instcombine -S | FileCheck %s
 ; Verify that the non-default calling conv doesn't prevent the libcall simplification
 
 @.str = private unnamed_addr constant [4 x i8] c"abc\00", align 1
 
 define arm_aapcscc i32 @_abs(i32 %i) nounwind readnone {
 ; CHECK: _abs
   %call = tail call arm_aapcscc i32 @abs(i32 %i) nounwind readnone
   ret i32 %call
-; CHECK: %[[ISPOS:.*]] = icmp sgt i32 %i, -1
+; CHECK: %[[ISPOS:.*]] = icmp sgt i32 %i, 0
 ; CHECK: %[[NEG:.*]] = sub i32 0, %i
 ; CHECK: %[[RET:.*]] = select i1 %[[ISPOS]], i32 %i, i32 %[[NEG]]
 ; CHECK: ret i32 %[[RET]]
 }
 
 declare arm_aapcscc i32 @abs(i32) nounwind readnone
 
 define arm_aapcscc i32 @_labs(i32 %i) nounwind readnone {
 ; CHECK: _labs
   %call = tail call arm_aapcscc i32 @labs(i32 %i) nounwind readnone
   ret i32 %call
-; CHECK: %[[ISPOS:.*]] = icmp sgt i32 %i, -1
+; CHECK: %[[ISPOS:.*]] = icmp sgt i32 %i, 0
 ; CHECK: %[[NEG:.*]] = sub i32 0, %i
 ; CHECK: %[[RET:.*]] = select i1 %[[ISPOS]], i32 %i, i32 %[[NEG]]
 ; CHECK: ret i32 %[[RET]]
 }
 
 declare arm_aapcscc i32 @labs(i32) nounwind readnone
 
 define arm_aapcscc i32 @_strlen1() {