[InstCombine]add testcase for sdiv canonicalizetion - NFC

llvm-svn: 357883

diff --git a/llvm/test/Transforms/InstCombine/sdiv-canonicalize.ll b/llvm/test/Transforms/InstCombine/sdiv-canonicalize.ll
new file mode 100644 (file)
index 0000000..7f5ff06
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/sdiv-canonicalize.ll
@@ -0,0 +1,80 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+define i32 @test_sdiv_canonicalize_op0(i32 %x, i32 %y) {
+; CHECK-LABEL: @test_sdiv_canonicalize_op0(
+; CHECK-NEXT:    [[NEG:%.*]] = sub nsw i32 0, [[X:%.*]]
+; CHECK-NEXT:    [[SDIV:%.*]] = sdiv i32 [[NEG]], [[Y:%.*]]
+; CHECK-NEXT:    ret i32 [[SDIV]]
+;
+  %neg = sub nsw i32 0, %x
+  %sdiv = sdiv i32 %neg, %y
+  ret i32 %sdiv
+}
+
+define i32 @test_sdiv_canonicalize_op1(i32 %x, i32 %z) {
+; CHECK-LABEL: @test_sdiv_canonicalize_op1(
+; CHECK-NEXT:    [[Y:%.*]] = mul i32 [[Z:%.*]], 3
+; CHECK-NEXT:    [[NEG:%.*]] = sub nsw i32 0, [[X:%.*]]
+; CHECK-NEXT:    [[SDIV:%.*]] = sdiv i32 [[Y]], [[NEG]]
+; CHECK-NEXT:    ret i32 [[SDIV]]
+;
+  %y = mul i32 %z, 3
+  %neg = sub nsw i32 0, %x
+  %sdiv = sdiv i32 %y, %neg
+  ret i32 %sdiv
+}
+
+define i32 @test_sdiv_canonicalize_nonsw(i32 %x, i32 %y) {
+; CHECK-LABEL: @test_sdiv_canonicalize_nonsw(
+; CHECK-NEXT:    [[NEG:%.*]] = sub i32 0, [[X:%.*]]
+; CHECK-NEXT:    [[SDIV:%.*]] = sdiv i32 [[NEG]], [[Y:%.*]]
+; CHECK-NEXT:    ret i32 [[SDIV]]
+;
+  %neg = sub i32 0, %x
+  %sdiv = sdiv i32 %neg, %y
+  ret i32 %sdiv
+}
+
+define <2 x i32> @test_sdiv_canonicalize_vec(<2 x i32> %x, <2 x i32> %y) {
+; CHECK-LABEL: @test_sdiv_canonicalize_vec(
+; CHECK-NEXT:    [[NEG:%.*]] = sub nsw <2 x i32> zeroinitializer, [[X:%.*]]
+; CHECK-NEXT:    [[SDIV:%.*]] = sdiv <2 x i32> [[NEG]], [[Y:%.*]]
+; CHECK-NEXT:    ret <2 x i32> [[SDIV]]
+;
+  %neg = sub nsw <2 x i32> <i32 0, i32 0>, %x
+  %sdiv = sdiv <2 x i32> %neg, %y
+  ret <2 x i32> %sdiv
+}
+
+define i32 @test_sdiv_canonicalize_multiple_uses(i32 %x, i32 %y) {
+; CHECK-LABEL: @test_sdiv_canonicalize_multiple_uses(
+; CHECK-NEXT:    [[NEG:%.*]] = sub nsw i32 0, [[X:%.*]]
+; CHECK-NEXT:    [[SDIV:%.*]] = sdiv i32 [[NEG]], [[Y:%.*]]
+; CHECK-NEXT:    [[SDIV2:%.*]] = sdiv i32 [[SDIV]], [[NEG]]
+; CHECK-NEXT:    ret i32 [[SDIV2]]
+;
+  %neg = sub nsw i32 0, %x
+  %sdiv = sdiv i32 %neg, %y
+  %sdiv2 = sdiv i32 %sdiv, %neg
+  ret i32 %sdiv2
+}
+
+; There is combination: (X/-CE) -> -(X/CE)
+; There is another combination: -(X/CE) -> (X/-CE)
+; Make sure don't combine them endless.
+
+@X = global i32 5
+
+define i64 @test_sdiv_canonicalize_constexpr(i64 %L1) {
+; currently opt folds (sub nsw i64 0, constexpr) -> (sub i64, 0, constexpr).
+; sdiv canonicalize requires a nsw sub.
+; CHECK-LABEL: @test_sdiv_canonicalize_constexpr(
+; CHECK-NEXT:    [[B4:%.*]] = sdiv i64 [[L1:%.*]], sub (i64 0, i64 ptrtoint (i32* @X to i64))
+; CHECK-NEXT:    ret i64 [[B4]]
+;
+  %v1 = ptrtoint i32* @X to i64
+  %B8 = sub nsw i64 0, %v1
+  %B4 = sdiv i64 %L1, %B8
+  ret i64 %B4
+}