Imported Upstream version 5.18.0.246

Former-commit-id: 0c7ce5b1a7851e13f22acfd379b7f9fb304e4833

external/llvm/test/Analysis/ValueTracking/signbits-extract-elt.ll

@@ -0,0 +1,28 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instsimplify -S | FileCheck %s
+
+; If computeKnownBits can do a simple look-through for extractelement
+; then instsimplify will know that %elt1 is non-negative at icmp.
+define i1 @computeKnownBits_look_through_extractelt(<2 x i8> %vecin) {
+; CHECK-LABEL: @computeKnownBits_look_through_extractelt(
+; CHECK-NEXT:    ret i1 false
+;
+  %vec = zext <2 x i8> %vecin to <2 x i32>
+  %elt1 = extractelement <2 x i32> %vec, i32 1
+  %bool = icmp slt i32 %elt1, 0
+  ret i1 %bool
+}
+
+; If computeNumSignBits can do a simple look-through for extractelement
+; then instsimplify will remove the ashr.
+define i32 @computeNumSignBits_look_through_extractelt(<2 x i1> %vecin) {
+; CHECK-LABEL: @computeNumSignBits_look_through_extractelt(
+; CHECK-NEXT:    [[VEC:%.*]] = sext <2 x i1> [[VEC:%.*]]in to <2 x i32>
+; CHECK-NEXT:    [[ELT0:%.*]] = extractelement <2 x i32> [[VEC]], i32 0
+; CHECK-NEXT:    ret i32 [[ELT0]]
+;
+  %vec = sext <2 x i1> %vecin to <2 x i32>
+  %elt0 = extractelement <2 x i32> %vec, i32 0
+  %ashr = ashr i32 %elt0, 5
+  ret i32 %ashr
+}