[llvm] [AArch64] Convert comparisons with 1 and -1 to 0 if it is profitable (PR #141151)

via llvm-commits llvm-commits at lists.llvm.org
Thu May 22 15:21:07 PDT 2025


llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-aarch64

Author: AZero13 (AZero13)

<details>
<summary>Changes</summary>

This relies on the fact that we can use tst and ands for comparions as by emitConditional.

I know there has to be a better way to do this, but this is the first draft because this is working and some feedback would be nice. 

Relies on https://github.com/llvm/llvm-project/pull/140999.

---

Patch is 43.04 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/141151.diff


14 Files Affected:

- (modified) llvm/lib/Target/AArch64/AArch64ISelLowering.cpp (+60-28) 
- (modified) llvm/test/CodeGen/AArch64/arm64-csel.ll (+2-3) 
- (modified) llvm/test/CodeGen/AArch64/check-sign-bit-before-extension.ll (+8-8) 
- (modified) llvm/test/CodeGen/AArch64/cmp-to-cmn.ll (+172) 
- (modified) llvm/test/CodeGen/AArch64/csel-subs-swapped.ll (+6-12) 
- (modified) llvm/test/CodeGen/AArch64/fptosi-sat-scalar.ll (+12-8) 
- (modified) llvm/test/CodeGen/AArch64/fptosi-sat-vector.ll (+6-4) 
- (modified) llvm/test/CodeGen/AArch64/select-constant-xor.ll (+2-2) 
- (modified) llvm/test/CodeGen/AArch64/signbit-shift.ll (+4-4) 
- (modified) llvm/test/CodeGen/AArch64/signbit-test.ll (+15-15) 
- (modified) llvm/test/CodeGen/AArch64/tbz-tbnz.ll (+240-66) 
- (modified) llvm/test/CodeGen/AArch64/typepromotion-signed.ll (+4-4) 
- (modified) llvm/test/CodeGen/AArch64/use-cr-result-of-dom-icmp-st.ll (+8-12) 
- (modified) llvm/test/CodeGen/AArch64/win64_vararg.ll (+4-4) 


``````````diff
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index b7f0bcfd015bc..15b9af83a293c 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -3647,6 +3647,16 @@ static bool isLegalArithImmed(uint64_t C) {
   return IsLegal;
 }
 
+bool isLegalCmpImmed(int64_t Immed) {
+  if (Immed == std::numeric_limits<int64_t>::min()) {
+    LLVM_DEBUG(dbgs() << "Illegal add imm " << Immed
+                      << ": avoid UB for INT64_MIN\n");
+    return false;
+  }
+  // Same encoding for add/sub, just flip the sign.
+  return isLegalArithImmed((uint64_t)std::abs(Immed));
+}
+
 static bool cannotBeIntMin(SDValue CheckedVal, SelectionDAG &DAG) {
   KnownBits KnownSrc = DAG.computeKnownBits(CheckedVal);
   return !KnownSrc.getSignedMinValue().isMinSignedValue();
@@ -4072,57 +4082,84 @@ static unsigned getCmpOperandFoldingProfit(SDValue Op) {
   return 0;
 }
 
+// emitComparison() converts comparison with one or negative one to comparison
+// with 0.
+static bool shouldBeAdjustedToZero(SDValue LHS, int64_t C, ISD::CondCode CC) {
+  // Only works for not signed values.
+  if (isUnsignedIntSetCC(CC))
+    return false;
+  // Only works for ANDS and AND.
+  if (LHS.getOpcode() != ISD::AND && (LHS.getOpcode() == ISD::ANDS))
+    return false;
+  if (C == 1 && (CC == ISD::SETLT || CC == ISD::SETGE))
+    return true;
+  if (C == -1 && (CC == ISD::SETLE || CC == ISD::SETGT))
+    return true;
+
+  return false;
+}
+
 static SDValue getAArch64Cmp(SDValue LHS, SDValue RHS, ISD::CondCode CC,
                              SDValue &AArch64cc, SelectionDAG &DAG,
                              const SDLoc &dl) {
   if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS.getNode())) {
     EVT VT = RHS.getValueType();
-    uint64_t C = RHSC->getZExtValue();
-    if (!isLegalArithImmed(C)) {
+    int64_t C = RHSC->getSExtValue();
+    // This is a special case for ands with cmn 1 so that emitComparison can
+    if (shouldBeAdjustedToZero(LHS, RHSC, CC)) {
+      if (C == 1) {
+        CC = (CC == ISD::SETLT) ? ISD::SETLE : ISD::SETGT;
+      } else {
+        // C is -1
+        CC = (CC == ISD::SETLE) ? ISD::SETLT : ISD::SETGE;
+      }
+      RHS = DAG.getConstant(0, dl, VT);
+    } else if (!isLegalCmpImmed(C)) {
       // Constant does not fit, try adjusting it by one?
       switch (CC) {
       default:
         break;
       case ISD::SETLT:
       case ISD::SETGE:
-        if ((VT == MVT::i32 && C != 0x80000000 &&
-             isLegalArithImmed((uint32_t)(C - 1))) ||
-            (VT == MVT::i64 && C != 0x80000000ULL &&
-             isLegalArithImmed(C - 1ULL))) {
+        if ((VT == MVT::i32 && C != INT32_MIN && isLegalCmpImmed(C - 1)) ||
+            (VT == MVT::i64 && C != INT64_MIN && isLegalCmpImmed(C - 1))) {
           CC = (CC == ISD::SETLT) ? ISD::SETLE : ISD::SETGT;
-          C = (VT == MVT::i32) ? (uint32_t)(C - 1) : C - 1;
+          C = C - 1;
+          if (VT == MVT::i32)
+            C &= 0xFFFFFFFF;
           RHS = DAG.getConstant(C, dl, VT);
         }
         break;
       case ISD::SETULT:
       case ISD::SETUGE:
-        if ((VT == MVT::i32 && C != 0 &&
-             isLegalArithImmed((uint32_t)(C - 1))) ||
-            (VT == MVT::i64 && C != 0ULL && isLegalArithImmed(C - 1ULL))) {
+        if ((VT == MVT::i32 && C != 0 && isLegalCmpImmed(C - 1)) ||
+            (VT == MVT::i64 && C != 0 && isLegalCmpImmed(C - 1))) {
           CC = (CC == ISD::SETULT) ? ISD::SETULE : ISD::SETUGT;
-          C = (VT == MVT::i32) ? (uint32_t)(C - 1) : C - 1;
+          C = C - 1;
+          if (VT == MVT::i32)
+            C &= 0xFFFFFFFF;
           RHS = DAG.getConstant(C, dl, VT);
         }
         break;
       case ISD::SETLE:
       case ISD::SETGT:
-        if ((VT == MVT::i32 && C != INT32_MAX &&
-             isLegalArithImmed((uint32_t)(C + 1))) ||
-            (VT == MVT::i64 && C != INT64_MAX &&
-             isLegalArithImmed(C + 1ULL))) {
+        if ((VT == MVT::i32 && C != INT32_MAX && isLegalCmpImmed(C + 1)) ||
+            (VT == MVT::i64 && C != INT64_MAX && isLegalCmpImmed(C + 1))) {
           CC = (CC == ISD::SETLE) ? ISD::SETLT : ISD::SETGE;
-          C = (VT == MVT::i32) ? (uint32_t)(C + 1) : C + 1;
+          C = C + 1;
+          if (VT == MVT::i32)
+            C &= 0xFFFFFFFF;
           RHS = DAG.getConstant(C, dl, VT);
         }
         break;
       case ISD::SETULE:
       case ISD::SETUGT:
-        if ((VT == MVT::i32 && C != UINT32_MAX &&
-             isLegalArithImmed((uint32_t)(C + 1))) ||
-            (VT == MVT::i64 && C != UINT64_MAX &&
-             isLegalArithImmed(C + 1ULL))) {
+        if ((VT == MVT::i32 && C != -1 && isLegalCmpImmed(C + 1)) ||
+            (VT == MVT::i64 && C != -1 && isLegalCmpImmed(C + 1))) {
           CC = (CC == ISD::SETULE) ? ISD::SETULT : ISD::SETUGE;
-          C = (VT == MVT::i32) ? (uint32_t)(C + 1) : C + 1;
+          C = C + 1;
+          if (VT == MVT::i32)
+            C &= 0xFFFFFFFF;
           RHS = DAG.getConstant(C, dl, VT);
         }
         break;
@@ -4141,7 +4178,7 @@ static SDValue getAArch64Cmp(SDValue LHS, SDValue RHS, ISD::CondCode CC,
   // can be turned into:
   //    cmp     w12, w11, lsl #1
   if (!isa<ConstantSDNode>(RHS) ||
-      !isLegalArithImmed(RHS->getAsAPIntVal().abs().getZExtValue())) {
+      !isLegalCmpImmed(RHS->getAsAPIntVal().getSExtValue())) {
     bool LHSIsCMN = isCMN(LHS, CC, DAG);
     bool RHSIsCMN = isCMN(RHS, CC, DAG);
     SDValue TheLHS = LHSIsCMN ? LHS.getOperand(1) : LHS;
@@ -17673,12 +17710,7 @@ bool AArch64TargetLowering::isLegalAddImmediate(int64_t Immed) const {
     return false;
   }
   // Same encoding for add/sub, just flip the sign.
-  Immed = std::abs(Immed);
-  bool IsLegal = ((Immed >> 12) == 0 ||
-                  ((Immed & 0xfff) == 0 && Immed >> 24 == 0));
-  LLVM_DEBUG(dbgs() << "Is " << Immed
-                    << " legal add imm: " << (IsLegal ? "yes" : "no") << "\n");
-  return IsLegal;
+  return isLegalArithImmed((uint64_t)std::abs(Immed));
 }
 
 bool AArch64TargetLowering::isLegalAddScalableImmediate(int64_t Imm) const {
diff --git a/llvm/test/CodeGen/AArch64/arm64-csel.ll b/llvm/test/CodeGen/AArch64/arm64-csel.ll
index 1cf99d1b31a8b..69fad57a683ac 100644
--- a/llvm/test/CodeGen/AArch64/arm64-csel.ll
+++ b/llvm/test/CodeGen/AArch64/arm64-csel.ll
@@ -100,9 +100,8 @@ define i32 @foo7(i32 %a, i32 %b) nounwind {
 ; CHECK-NEXT:    subs w8, w0, w1
 ; CHECK-NEXT:    cneg w9, w8, mi
 ; CHECK-NEXT:    cmn w8, #1
-; CHECK-NEXT:    csel w10, w9, w0, lt
-; CHECK-NEXT:    cmp w8, #0
-; CHECK-NEXT:    csel w0, w10, w9, ge
+; CHECK-NEXT:    csel w8, w9, w0, lt
+; CHECK-NEXT:    csel w0, w8, w9, gt
 ; CHECK-NEXT:    ret
 entry:
   %sub = sub nsw i32 %a, %b
diff --git a/llvm/test/CodeGen/AArch64/check-sign-bit-before-extension.ll b/llvm/test/CodeGen/AArch64/check-sign-bit-before-extension.ll
index 8fbed8bfdb3fd..1d60929f2b94c 100644
--- a/llvm/test/CodeGen/AArch64/check-sign-bit-before-extension.ll
+++ b/llvm/test/CodeGen/AArch64/check-sign-bit-before-extension.ll
@@ -14,8 +14,8 @@ define i32 @f_i8_sign_extend_inreg(i8 %in, i32 %a, i32 %b) nounwind {
 ; CHECK-LABEL: f_i8_sign_extend_inreg:
 ; CHECK:       // %bb.0: // %entry
 ; CHECK-NEXT:    sxtb w8, w0
-; CHECK-NEXT:    cmp w8, #0
-; CHECK-NEXT:    csel w8, w1, w2, ge
+; CHECK-NEXT:    cmn w8, #1
+; CHECK-NEXT:    csel w8, w1, w2, gt
 ; CHECK-NEXT:    add w0, w8, w0, uxtb
 ; CHECK-NEXT:    ret
 entry:
@@ -36,8 +36,8 @@ define i32 @f_i16_sign_extend_inreg(i16 %in, i32 %a, i32 %b) nounwind {
 ; CHECK-LABEL: f_i16_sign_extend_inreg:
 ; CHECK:       // %bb.0: // %entry
 ; CHECK-NEXT:    sxth w8, w0
-; CHECK-NEXT:    cmp w8, #0
-; CHECK-NEXT:    csel w8, w1, w2, ge
+; CHECK-NEXT:    cmn w8, #1
+; CHECK-NEXT:    csel w8, w1, w2, gt
 ; CHECK-NEXT:    add w0, w8, w0, uxth
 ; CHECK-NEXT:    ret
 entry:
@@ -57,8 +57,8 @@ B:
 define i64 @f_i32_sign_extend_inreg(i32 %in, i64 %a, i64 %b) nounwind {
 ; CHECK-LABEL: f_i32_sign_extend_inreg:
 ; CHECK:       // %bb.0: // %entry
-; CHECK-NEXT:    cmp w0, #0
-; CHECK-NEXT:    csel x8, x1, x2, ge
+; CHECK-NEXT:    cmn w0, #1
+; CHECK-NEXT:    csel x8, x1, x2, gt
 ; CHECK-NEXT:    add x0, x8, w0, uxtw
 ; CHECK-NEXT:    ret
 entry:
@@ -145,8 +145,8 @@ define i64 @f_i32_sign_extend_i64(i32 %in, i64 %a, i64 %b) nounwind {
 ; CHECK:       // %bb.0: // %entry
 ; CHECK-NEXT:    // kill: def $w0 killed $w0 def $x0
 ; CHECK-NEXT:    sxtw x8, w0
-; CHECK-NEXT:    cmp x8, #0
-; CHECK-NEXT:    csel x8, x1, x2, ge
+; CHECK-NEXT:    cmn x8, #1
+; CHECK-NEXT:    csel x8, x1, x2, gt
 ; CHECK-NEXT:    add x0, x8, w0, uxtw
 ; CHECK-NEXT:    ret
 entry:
diff --git a/llvm/test/CodeGen/AArch64/cmp-to-cmn.ll b/llvm/test/CodeGen/AArch64/cmp-to-cmn.ll
index e87d43161a895..c5fd9b63cce97 100644
--- a/llvm/test/CodeGen/AArch64/cmp-to-cmn.ll
+++ b/llvm/test/CodeGen/AArch64/cmp-to-cmn.ll
@@ -430,3 +430,175 @@ entry:
   %cmp = icmp ne i32 %conv, %add
   ret i1 %cmp
 }
+
+define i1 @cmn_large_imm(i32 %a) {
+; CHECK-LABEL: cmn_large_imm:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    mov w8, #64765 // =0xfcfd
+; CHECK-NEXT:    movk w8, #64764, lsl #16
+; CHECK-NEXT:    cmp w0, w8
+; CHECK-NEXT:    cset w0, gt
+; CHECK-NEXT:    ret
+  %cmp = icmp sgt i32 %a, -50529027
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_slt(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_slt:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, le
+; CHECK-NEXT:    ret
+  %cmp = icmp slt i32 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_slt_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_slt_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, le
+; CHECK-NEXT:    ret
+  %cmp = icmp slt i64 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_sge(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_sge:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, gt
+; CHECK-NEXT:    ret
+  %cmp = icmp sge i32 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_sge_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_sge_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, gt
+; CHECK-NEXT:    ret
+  %cmp = icmp sge i64 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_uge(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_uge:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, hi
+; CHECK-NEXT:    ret
+  %cmp = icmp uge i32 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_uge_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_uge_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, hi
+; CHECK-NEXT:    ret
+  %cmp = icmp uge i64 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_ult(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_ult:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, ls
+; CHECK-NEXT:    ret
+  %cmp = icmp ult i32 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_ult_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_ult_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4079, lsl #12 // =16707584
+; CHECK-NEXT:    cset w0, ls
+; CHECK-NEXT:    ret
+  %cmp = icmp ult i64 %x, -16707583
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_sle(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_sle:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, lt
+; CHECK-NEXT:    ret
+  %cmp = icmp sle i32 %x, -16773121
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_sle_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_sle_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, lt
+; CHECK-NEXT:    ret
+  %cmp = icmp sle i64 %x, -16773121
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_sgt(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_sgt:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, ge
+; CHECK-NEXT:    ret
+  %cmp = icmp sgt i32 %x, -16773121
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_sgt_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_sgt_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, ge
+; CHECK-NEXT:    ret
+  %cmp = icmp sgt i64 %x, -16773121
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_ule(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_ule:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, lo
+; CHECK-NEXT:    ret
+  %cmp = icmp ule i32 %x, -16773121
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_ule_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_ule_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, lo
+; CHECK-NEXT:    ret
+  %cmp = icmp ule i64 %x, -16773121
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_ugt(i32 %x) {
+; CHECK-LABEL: almost_immediate_neg_ugt:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn w0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, hs
+; CHECK-NEXT:    ret
+  %cmp = icmp ugt i32 %x, -16773121
+  ret i1 %cmp
+}
+
+define i1 @almost_immediate_neg_ugt_64(i64 %x) {
+; CHECK-LABEL: almost_immediate_neg_ugt_64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    cmn x0, #4095, lsl #12 // =16773120
+; CHECK-NEXT:    cset w0, hs
+; CHECK-NEXT:    ret
+  %cmp = icmp ugt i64 %x, -16773121
+  ret i1 %cmp
+}
diff --git a/llvm/test/CodeGen/AArch64/csel-subs-swapped.ll b/llvm/test/CodeGen/AArch64/csel-subs-swapped.ll
index 3971da27cdddc..7d2c7854baf3d 100644
--- a/llvm/test/CodeGen/AArch64/csel-subs-swapped.ll
+++ b/llvm/test/CodeGen/AArch64/csel-subs-swapped.ll
@@ -44,10 +44,8 @@ define i32 @sge_i32(i32 %x) {
 ; CHECK-LABEL: sge_i32:
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    mov w8, #-2097152 // =0xffe00000
-; CHECK-NEXT:    mov w9, #-2097153 // =0xffdfffff
-; CHECK-NEXT:    sub w8, w8, w0
-; CHECK-NEXT:    cmp w0, w9
-; CHECK-NEXT:    csel w0, w0, w8, gt
+; CHECK-NEXT:    subs w8, w8, w0
+; CHECK-NEXT:    csel w0, w0, w8, le
 ; CHECK-NEXT:    ret
   %cmp = icmp sge i32 %x, -2097152
   %sub = sub i32 -2097152, %x
@@ -72,10 +70,8 @@ define i32 @sle_i32(i32 %x) {
 ; CHECK-LABEL: sle_i32:
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    mov w8, #-2097152 // =0xffe00000
-; CHECK-NEXT:    mov w9, #-2097151 // =0xffe00001
-; CHECK-NEXT:    sub w8, w8, w0
-; CHECK-NEXT:    cmp w0, w9
-; CHECK-NEXT:    csel w0, w0, w8, lt
+; CHECK-NEXT:    subs w8, w8, w0
+; CHECK-NEXT:    csel w0, w0, w8, ge
 ; CHECK-NEXT:    ret
   %cmp = icmp sle i32 %x, -2097152
   %sub = sub i32 -2097152, %x
@@ -128,10 +124,8 @@ define i32 @ule_i32(i32 %x) {
 ; CHECK-LABEL: ule_i32:
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    mov w8, #-2097152 // =0xffe00000
-; CHECK-NEXT:    mov w9, #-2097151 // =0xffe00001
-; CHECK-NEXT:    sub w8, w8, w0
-; CHECK-NEXT:    cmp w0, w9
-; CHECK-NEXT:    csel w0, w0, w8, lo
+; CHECK-NEXT:    subs w8, w8, w0
+; CHECK-NEXT:    csel w0, w0, w8, hs
 ; CHECK-NEXT:    ret
   %cmp = icmp ule i32 %x, -2097152
   %sub = sub i32 -2097152, %x
diff --git a/llvm/test/CodeGen/AArch64/fptosi-sat-scalar.ll b/llvm/test/CodeGen/AArch64/fptosi-sat-scalar.ll
index 39e2db3a52d2c..b766da2a3a829 100644
--- a/llvm/test/CodeGen/AArch64/fptosi-sat-scalar.ll
+++ b/llvm/test/CodeGen/AArch64/fptosi-sat-scalar.ll
@@ -23,8 +23,9 @@ define i1 @test_signed_i1_f32(float %f) nounwind {
 ; CHECK-SD-LABEL: test_signed_i1_f32:
 ; CHECK-SD:       // %bb.0:
 ; CHECK-SD-NEXT:    fcvtzs w8, s0
-; CHECK-SD-NEXT:    ands w8, w8, w8, asr #31
-; CHECK-SD-NEXT:    csinv w8, w8, wzr, ge
+; CHECK-SD-NEXT:    and w8, w8, w8, asr #31
+; CHECK-SD-NEXT:    cmn w8, #1
+; CHECK-SD-NEXT:    csinv w8, w8, wzr, gt
 ; CHECK-SD-NEXT:    and w0, w8, #0x1
 ; CHECK-SD-NEXT:    ret
 ;
@@ -268,8 +269,9 @@ define i1 @test_signed_i1_f64(double %f) nounwind {
 ; CHECK-SD-LABEL: test_signed_i1_f64:
 ; CHECK-SD:       // %bb.0:
 ; CHECK-SD-NEXT:    fcvtzs w8, d0
-; CHECK-SD-NEXT:    ands w8, w8, w8, asr #31
-; CHECK-SD-NEXT:    csinv w8, w8, wzr, ge
+; CHECK-SD-NEXT:    and w8, w8, w8, asr #31
+; CHECK-SD-NEXT:    cmn w8, #1
+; CHECK-SD-NEXT:    csinv w8, w8, wzr, gt
 ; CHECK-SD-NEXT:    and w0, w8, #0x1
 ; CHECK-SD-NEXT:    ret
 ;
@@ -518,16 +520,18 @@ define i1 @test_signed_i1_f16(half %f) nounwind {
 ; CHECK-SD-CVT:       // %bb.0:
 ; CHECK-SD-CVT-NEXT:    fcvt s0, h0
 ; CHECK-SD-CVT-NEXT:    fcvtzs w8, s0
-; CHECK-SD-CVT-NEXT:    ands w8, w8, w8, asr #31
-; CHECK-SD-CVT-NEXT:    csinv w8, w8, wzr, ge
+; CHECK-SD-CVT-NEXT:    and w8, w8, w8, asr #31
+; CHECK-SD-CVT-NEXT:    cmn w8, #1
+; CHECK-SD-CVT-NEXT:    csinv w8, w8, wzr, gt
 ; CHECK-SD-CVT-NEXT:    and w0, w8, #0x1
 ; CHECK-SD-CVT-NEXT:    ret
 ;
 ; CHECK-SD-FP16-LABEL: test_signed_i1_f16:
 ; CHECK-SD-FP16:       // %bb.0:
 ; CHECK-SD-FP16-NEXT:    fcvtzs w8, h0
-; CHECK-SD-FP16-NEXT:    ands w8, w8, w8, asr #31
-; CHECK-SD-FP16-NEXT:    csinv w8, w8, wzr, ge
+; CHECK-SD-FP16-NEXT:    and w8, w8, w8, asr #31
+; CHECK-SD-FP16-NEXT:    cmn w8, #1
+; CHECK-SD-FP16-NEXT:    csinv w8, w8, wzr, gt
 ; CHECK-SD-FP16-NEXT:    and w0, w8, #0x1
 ; CHECK-SD-FP16-NEXT:    ret
 ;
diff --git a/llvm/test/CodeGen/AArch64/fptosi-sat-vector.ll b/llvm/test/CodeGen/AArch64/fptosi-sat-vector.ll
index a33b1ef569fc3..3d7bcf6409438 100644
--- a/llvm/test/CodeGen/AArch64/fptosi-sat-vector.ll
+++ b/llvm/test/CodeGen/AArch64/fptosi-sat-vector.ll
@@ -2371,10 +2371,12 @@ define <2 x i1> @test_signed_v2f64_v2i1(<2 x double> %f) {
 ; CHECK-SD-NEXT:    mov d1, v0.d[1]
 ; CHECK-SD-NEXT:    fcvtzs w9, d0
 ; CHECK-SD-NEXT:    fcvtzs w8, d1
-; CHECK-SD-NEXT:    ands w8, w8, w8, asr #31
-; CHECK-SD-NEXT:    csinv w8, w8, wzr, ge
-; CHECK-SD-NEXT:    ands w9, w9, w9, asr #31
-; CHECK-SD-NEXT:    csinv w9, w9, wzr, ge
+; CHECK-SD-NEXT:    and w9, w9, w9, asr #31
+; CHECK-SD-NEXT:    and w8, w8, w8, asr #31
+; CHECK-SD-NEXT:    cmn w8, #1
+; CHECK-SD-NEXT:    csinv w8, w8, wzr, gt
+; CHECK-SD-NEXT:    cmn w9, #1
+; CHECK-SD-NEXT:    csinv w9, w9, wzr, gt
 ; CHECK-SD-NEXT:    fmov s0, w9
 ; CHECK-SD-NEXT:    mov v0.s[1], w8
 ; CHECK-SD-NEXT:    // kill: def $d0 killed $d0 killed $q0
diff --git a/llvm/test/CodeGen/AArch64/select-constant-xor.ll b/llvm/test/CodeGen/AArch64/select-constant-xor.ll
index 6803411f66896..fe9a2c0fad830 100644
--- a/llvm/test/CodeGen/AArch64/select-constant-xor.ll
+++ b/llvm/test/CodeGen/AArch64/select-constant-xor.ll
@@ -168,8 +168,8 @@ define i32 @icmpasreq(i32 %input, i32 %a, i32 %b) {
 define i32 @icmpasrne(i32 %input, i32 %a, i32 %b) {
 ; CHECK-SD-LABEL: icmpasrne:
 ; CHECK-SD:       // %bb.0:
-; CHECK-SD-NEXT:    cmp w0, #0
-; CHECK-SD-NEXT:    csel w0, w1, w2, ge
+; CHECK-SD-NEXT:    cmn w0, #1
+; CHECK-SD-NEXT:    csel w0, w1, w2, gt
 ; CHECK-SD-NEXT:    ret
 ;
 ; CHECK-GI-LABEL: icmpasrne:
diff --git a/llvm/test/CodeGen/AArch64/signbit-shift.ll b/llvm/test/CodeGen/AArch64/signbit-shift.ll
index 253ea1cab91fb..0e6da326a31f4 100644
--- a/llvm/test/CodeGen/AArch64/signbit-shift.ll
+++ b/llvm/test/CodeGen/AArch64/signbit-shift.ll
@@ -43,8 +43,8 @@ define i32 @sel_ifpos_tval_bigger(i32 %x) {
 ; CHECK-LABEL: sel_ifpos_tval_bigger:
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    mov w8, #41 // =0x29
-; CHECK-NEXT:    cmp w0, #0
-; CHECK-NEXT:    cinc w0, w8, ge
+; CHECK-NEXT:    cmn w0, #1
+; CHECK-NEXT:    cinc w0, w8, gt
 ; CHECK-NEXT:    ret
   %c = icmp sgt i32 %x, -1
   %r = select i1 %c, i32 42, i32 41
@@ -91,8 +91,8 @@ define i32 @sel_ifpos_fval_bigger(i32 %x) {
 ; CHECK-LABEL: sel_ifpos_fval_bigger:
 ; CHECK:       // %bb.0:
 ; CHECK-NEXT:    mov w8, #41 // =0x29
-; CHECK-NEXT:    cmp w0, #0
-; CHECK-NEXT:    cinc w0, w8, lt
+; CHECK-NEXT:    cmn w0, #1
+; CHECK-NEXT:    cinc w0, w8, le
 ; CHECK-NEXT:    ret
   %c = icmp sgt i32 %x, -1
   %r = select i1 %c, i32 41, i32 42
diff --git a/llvm/test/CodeGen/AArch64/signbit-test.ll b/llvm/test/CodeGen/AArch64/signbit-test.ll
index f5eaf80cf7f8d..c74a934ee09d8 100644
--- a/llvm/test/CodeGen/AArch64/signbit-test.ll
+++ b/llvm/test/CodeGen/AArch64/signbit-test.ll
@@ -4,9 +4,9 @@
 define i64 @test...
[truncated]

``````````

</details>


https://github.com/llvm/llvm-project/pull/141151


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