[llvm] s390x: pattern match saturated truncation (PR #155377)

[Ulrich Weigand via llvm-commits]

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@@ -1067,6 +1067,15 @@ def vsplat_imm_eq_1 : PatFrag<(ops), (build_vector), [{
 }]>;
 def z_vzext1 : PatFrag<(ops node:$x), (and node:$x, vsplat_imm_eq_1)>;
 
+def vsplat_imm_eq_s32_min : PatFrag<(ops), (build_vector), [{
+  APInt Imm;
+  return ISD::isConstantSplatVector(N, Imm) && Imm.getSExtValue() == -32768;
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uweigand wrote:

Ah, right.  You can probably generalize this function to determine the type (from `N`) and check for the type's minimum/maximum values programmatically.

https://github.com/llvm/llvm-project/pull/155377