[InstCombine] Add additional known bits folding tests; NFC

llvm/test/Transforms/InstCombine/known-bits.ll

@@ -0,0 +1,79 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -instcombine -expensive-combines=0 < %s | FileCheck %s --check-prefixes=CHECK,EXPENSIVE-OFF
+; RUN: opt -S -instcombine -expensive-combines=1 < %s | FileCheck %s --check-prefixes=CHECK,EXPENSIVE-ON
+
+define void @test_shl(i1 %x) {
+; EXPENSIVE-OFF-LABEL: @test_shl(
+; EXPENSIVE-OFF-NEXT:    [[Y:%.*]] = zext i1 [[X:%.*]] to i8
+; EXPENSIVE-OFF-NEXT:    [[Z:%.*]] = shl i8 64, [[Y]]
+; EXPENSIVE-OFF-NEXT:    [[A:%.*]] = and i8 [[Z]], 1
+; EXPENSIVE-OFF-NEXT:    call void @sink(i8 [[A]])
+; EXPENSIVE-OFF-NEXT:    ret void
+;
+; EXPENSIVE-ON-LABEL: @test_shl(
+; EXPENSIVE-ON-NEXT:    call void @sink(i8 0)
+; EXPENSIVE-ON-NEXT:    ret void
+;
+  %y = zext i1 %x to i8
+  %z = shl i8 64, %y
+  %a = and i8 %z, 1
+  call void @sink(i8 %a)
+  ret void
+}
+
+define void @test_lshr(i1 %x) {
+; EXPENSIVE-OFF-LABEL: @test_lshr(
+; EXPENSIVE-OFF-NEXT:    [[Y:%.*]] = zext i1 [[X:%.*]] to i8
+; EXPENSIVE-OFF-NEXT:    [[Z:%.*]] = lshr i8 64, [[Y]]
+; EXPENSIVE-OFF-NEXT:    [[A:%.*]] = and i8 [[Z]], 1
+; EXPENSIVE-OFF-NEXT:    call void @sink(i8 [[A]])
+; EXPENSIVE-OFF-NEXT:    ret void
+;
+; EXPENSIVE-ON-LABEL: @test_lshr(
+; EXPENSIVE-ON-NEXT:    call void @sink(i8 0)
+; EXPENSIVE-ON-NEXT:    ret void
+;
+  %y = zext i1 %x to i8
+  %z = lshr i8 64, %y
+  %a = and i8 %z, 1
+  call void @sink(i8 %a)
+  ret void
+}
+
+define void @test_ashr(i1 %x) {
+; EXPENSIVE-OFF-LABEL: @test_ashr(
+; EXPENSIVE-OFF-NEXT:    [[Y:%.*]] = zext i1 [[X:%.*]] to i8
+; EXPENSIVE-OFF-NEXT:    [[Z:%.*]] = ashr i8 -16, [[Y]]
+; EXPENSIVE-OFF-NEXT:    [[A:%.*]] = and i8 [[Z]], 3
+; EXPENSIVE-OFF-NEXT:    call void @sink(i8 [[A]])
+; EXPENSIVE-OFF-NEXT:    ret void
+;
+; EXPENSIVE-ON-LABEL: @test_ashr(
+; EXPENSIVE-ON-NEXT:    call void @sink(i8 0)
+; EXPENSIVE-ON-NEXT:    ret void
+;
+  %y = zext i1 %x to i8
+  %z = ashr i8 -16, %y
+  %a = and i8 %z, 3
+  call void @sink(i8 %a)
+  ret void
+}
+
+define void @test_udiv(i8 %x) {
+; EXPENSIVE-OFF-LABEL: @test_udiv(
+; EXPENSIVE-OFF-NEXT:    [[Y:%.*]] = udiv i8 10, [[X:%.*]]
+; EXPENSIVE-OFF-NEXT:    [[Z:%.*]] = and i8 [[Y]], 64
+; EXPENSIVE-OFF-NEXT:    call void @sink(i8 [[Z]])
+; EXPENSIVE-OFF-NEXT:    ret void
+;
+; EXPENSIVE-ON-LABEL: @test_udiv(
+; EXPENSIVE-ON-NEXT:    call void @sink(i8 0)
+; EXPENSIVE-ON-NEXT:    ret void
+;
+  %y = udiv i8 10, %x
+  %z = and i8 %y, 64
+  call void @sink(i8 %z)
+  ret void
+}
+
+declare void @sink(i8)