[llvm] [AArch64][GlobalISel] Combine trunc_nsw(smin) to truncsat (PR #218605)

[Matt Arsenault via llvm-commits]

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@@ -6290,14 +6290,24 @@ bool CombinerHelper::matchTruncSSatS(MachineInstr &MI,
 
   APInt SignedMax = APInt::getSignedMaxValue(NumDstBits).sext(NumSrcBits);
   APInt SignedMin = APInt::getSignedMinValue(NumDstBits).sext(NumSrcBits);
-  return mi_match(Src, MRI,
-                  m_GSMin(m_GSMax(m_Reg(MatchInfo),
-                                  m_SpecificICstOrSplat(SignedMin)),
-                          m_SpecificICstOrSplat(SignedMax))) ||
-         mi_match(Src, MRI,
-                  m_GSMax(m_GSMin(m_Reg(MatchInfo),
-                                  m_SpecificICstOrSplat(SignedMax)),
-                          m_SpecificICstOrSplat(SignedMin)));
+  if (mi_match(
+          Src, MRI,
+          m_GSMin(m_GSMax(m_Reg(MatchInfo), m_SpecificICstOrSplat(SignedMin)),
+                  m_SpecificICstOrSplat(SignedMax))) ||
+      mi_match(
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arsenm wrote:

might as well make these 2 separate ifs 

https://github.com/llvm/llvm-project/pull/218605