[llvm] [ValueTracking] Improve KnownBits for signed min-max clamping (PR #120576)

[Yingwei Zheng via llvm-commits]

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@@ -0,0 +1,174 @@
+; RUN: opt < %s -passes=aggressive-instcombine -mtriple=x86_64 -S | FileCheck %s
+
+; This LIT test checks if TruncInstCombine pass correctly recognizes the
+; constraints from a signed min-max clamp. The clamp is a sequence of smin and
+; smax instructions limiting a variable into a range, smin <= x <= smax.
+
+declare i16 @llvm.smin.i16(i16, i16)
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dtcxzyw wrote:

Declaration of intrinsics is unnecessary.

https://github.com/llvm/llvm-project/pull/120576