[llvm] [GlobalISel] Add computeNumSignBits for SHL (PR #152067)

[David Green via llvm-commits]

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@@ -0,0 +1,110 @@
+# NOTE: Assertions have been autogenerated by utils/update_givaluetracking_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple aarch64 -passes="print<gisel-value-tracking>" %s -o - 2>&1 | FileCheck %s
+
+---
+name:            Cst
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davemgreen wrote:

Can you also add test cases for the transformed added above, like shl(zext) and shl(sext). I think it should be able to add tests for `shl(<something with sign bits>, C)` too, so maybe `shl(ashr(X, C1), C2)`

https://github.com/llvm/llvm-project/pull/152067