[X86] Add reduced test case for #114360

Author: RKSimon

llvm/test/CodeGen/X86/pr114360.ll

@@ -0,0 +1,15 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=x86_64- -debug-counter=dagcombine=0 | FileCheck %s
+
+; BUG: shrinkAndImmediate folds away the AND after the ZEXT has already been folded away to SUBREG_TO_REG losing implicit zext.
+define i64 @test() {
+; CHECK-LABEL: test:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movabsq $-4294967295, %rax # imm = 0xFFFFFFFF00000001
+; CHECK-NEXT:    retq
+  %x = bitcast i64 u0xffffffff00000001 to i64
+  %t = trunc i64 %x to i32
+  %a = and i32 %t, 1
+  %e = zext i32 %a to i64
+  ret i64 %e
+}