[InstCombine] matchThreeWayIntCompare(): commutativity awareness

Summary:
`matchThreeWayIntCompare()` looks for
```
   select i1 (a == b),
          i32 Equal,
          i32 (select i1 (a < b), i32 Less, i32 Greater)
```
but both of these selects/compares can be in it's commuted form,
so out of 8 variants, only the two most basic ones is handled.
This fixes regression being introduced in D66232.

Reviewers: spatel, nikic, efriedma, xbolva00

Reviewed By: spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66607

llvm-svn: 369841

1 files changed, 24 insertions, 52 deletions

diff --git a/llvm/test/Transforms/InstCombine/unrecognized_three-way-comparison.ll b/llvm/test/Transforms/InstCombine/unrecognized_three-way-comparison.ll
index 1ca16778299..14e0b557394 100644
--- a/llvm/test/Transforms/InstCombine/unrecognized_three-way-comparison.ll
+++ b/llvm/test/Transforms/InstCombine/unrecognized_three-way-comparison.ll
@@ -36,14 +36,10 @@ exit:
 define i32 @compare_against_zero(i32 %x) {
 ; CHECK-LABEL: @compare_against_zero(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[X:%.*]], 0
-; CHECK-NEXT:    [[CMP2_INV:%.*]] = icmp sgt i32 [[X]], -1
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2_INV]], i32 1, i32 -1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 0, i32 [[SELECT1]]
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 0
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 42
@@ -96,14 +92,10 @@ exit:
 define i32 @compare_against_two(i32 %x) {
 ; CHECK-LABEL: @compare_against_two(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[X:%.*]], 2
-; CHECK-NEXT:    [[CMP2_INV:%.*]] = icmp sgt i32 [[X]], 1
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2_INV]], i32 1, i32 -1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 0, i32 [[SELECT1]]
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 2
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 42
@@ -497,13 +489,10 @@ define i32 @compare_against_fortytwo_commutatibility_1(i32 %x) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[CMP1:%.*]] = icmp ne i32 [[X:%.*]], 42
 ; CHECK-NEXT:    call void @use1(i1 [[CMP1]])
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[X]], 42
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2]], i32 -1, i32 1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 [[SELECT1]], i32 0
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X]], 42
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 84
@@ -527,14 +516,10 @@ exit:
 define i32 @compare_against_fortytwo_commutatibility_2(i32 %x) {
 ; CHECK-LABEL: @compare_against_fortytwo_commutatibility_2(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[X:%.*]], 42
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[X]], 41
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2]], i32 1, i32 -1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 0, i32 [[SELECT1]]
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], 42
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 84
@@ -559,13 +544,10 @@ define i32 @compare_against_fortytwo_commutatibility_3(i32 %x) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[CMP1:%.*]] = icmp ne i32 [[X:%.*]], 42
 ; CHECK-NEXT:    call void @use1(i1 [[CMP1]])
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[X]], 41
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2]], i32 1, i32 -1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 [[SELECT1]], i32 0
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X]], 42
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 84
@@ -616,14 +598,10 @@ exit:
 define i32 @compare_against_arbitrary_value_commutativity1(i32 %x, i32 %c) {
 ; CHECK-LABEL: @compare_against_arbitrary_value_commutativity1(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[X:%.*]], [[C:%.*]]
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[C]], [[X]]
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2]], i32 -1, i32 1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 0, i32 [[SELECT1]]
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X:%.*]], [[C:%.*]]
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 42
@@ -648,13 +626,10 @@ define i32 @compare_against_arbitrary_value_commutativity2(i32 %x, i32 %c) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[CMP1:%.*]] = icmp ne i32 [[X:%.*]], [[C:%.*]]
 ; CHECK-NEXT:    call void @use1(i1 [[CMP1]])
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[X]], [[C]]
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2]], i32 -1, i32 1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 [[SELECT1]], i32 0
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X]], [[C]]
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 42
@@ -680,13 +655,10 @@ define i32 @compare_against_arbitrary_value_commutativity3(i32 %x, i32 %c) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[CMP1:%.*]] = icmp ne i32 [[X:%.*]], [[C:%.*]]
 ; CHECK-NEXT:    call void @use1(i1 [[CMP1]])
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[C]], [[X]]
-; CHECK-NEXT:    [[SELECT1:%.*]] = select i1 [[CMP2]], i32 -1, i32 1
-; CHECK-NEXT:    [[SELECT2:%.*]] = select i1 [[CMP1]], i32 [[SELECT1]], i32 0
-; CHECK-NEXT:    [[COND:%.*]] = icmp sgt i32 [[SELECT2]], 0
-; CHECK-NEXT:    br i1 [[COND]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = icmp sgt i32 [[X]], [[C]]
+; CHECK-NEXT:    br i1 [[TMP0]], label [[CALLFOO:%.*]], label [[EXIT:%.*]]
 ; CHECK:       callfoo:
-; CHECK-NEXT:    call void @foo(i32 [[SELECT2]])
+; CHECK-NEXT:    call void @foo(i32 1)
 ; CHECK-NEXT:    br label [[EXIT]]
 ; CHECK:       exit:
 ; CHECK-NEXT:    ret i32 42