[llvm] [InstCombine] Fold `(icmp eq/ne (or (select cond, 0/NZ, 0/NZ), X), 0)` (PR #88183)
Yingwei Zheng via llvm-commits
llvm-commits at lists.llvm.org
Sat Aug 3 10:50:44 PDT 2024
================
@@ -0,0 +1,295 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+declare void @use.i8(i8)
+declare void @use.i1(i1)
+define i1 @src_tv_eq(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_tv_eq(
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
+; CHECK-NEXT: [[R:%.*]] = and i1 [[TMP1]], [[C0:%.*]]
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 0, i8 %y
+ %selx = or i8 %sel, %x
+ %r = icmp eq i8 %selx, 0
+ ret i1 %r
+}
+
+define i1 @src_tv_eq_multiuse_or_fail(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_tv_eq_multiuse_or_fail(
+; CHECK-NEXT: [[Y:%.*]] = add nuw i8 [[YY:%.*]], 1
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C0:%.*]], i8 0, i8 [[Y]]
+; CHECK-NEXT: [[SELX:%.*]] = or i8 [[SEL]], [[X:%.*]]
+; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[SELX]], 0
+; CHECK-NEXT: call void @use.i8(i8 [[SELX]])
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 0, i8 %y
+ %selx = or i8 %sel, %x
+ %r = icmp eq i8 %selx, 0
+ call void @use.i8(i8 %selx)
+ ret i1 %r
+}
+
+define i1 @src_tv_eq_fail_tv_nonzero(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_tv_eq_fail_tv_nonzero(
+; CHECK-NEXT: [[Y:%.*]] = add nsw i8 [[YY:%.*]], 1
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C0:%.*]], i8 1, i8 [[Y]]
+; CHECK-NEXT: [[SELX:%.*]] = or i8 [[SEL]], [[X:%.*]]
+; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[SELX]], 0
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nsw i8 %yy, 1
+ %sel = select i1 %c0, i8 1, i8 %y
+ %selx = or i8 %sel, %x
+ %r = icmp eq i8 %selx, 0
+ ret i1 %r
+}
+
+define i1 @src_fv_ne(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_fv_ne(
+; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i8 [[X:%.*]], 0
+; CHECK-NEXT: [[R:%.*]] = or i1 [[TMP1]], [[C0:%.*]]
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 %y, i8 0
+ %selx = or i8 %sel, %x
+ %r = icmp ne i8 %selx, 0
+ ret i1 %r
+}
+
+define i1 @src_fv_ne_fail_maybe_zero(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_fv_ne_fail_maybe_zero(
+; CHECK-NEXT: [[Y:%.*]] = add nsw i8 [[YY:%.*]], 1
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C0:%.*]], i8 [[Y]], i8 0
+; CHECK-NEXT: [[SELX:%.*]] = or i8 [[SEL]], [[X:%.*]]
+; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[SELX]], 0
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nsw i8 %yy, 1
+ %sel = select i1 %c0, i8 %y, i8 0
+ %selx = or i8 %sel, %x
+ %r = icmp ne i8 %selx, 0
+ ret i1 %r
+}
+
+define i1 @src_tv_ne(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_tv_ne(
+; CHECK-NEXT: [[TMP1:%.*]] = xor i1 [[C0:%.*]], true
+; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i8 [[X:%.*]], 0
+; CHECK-NEXT: [[R:%.*]] = or i1 [[TMP2]], [[TMP1]]
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 0, i8 %y
+ %selx = or i8 %sel, %x
+ %r = icmp ne i8 %selx, 0
+ ret i1 %r
+}
+
+define i1 @src_tv_ne_fail_cmp_nonzero(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_tv_ne_fail_cmp_nonzero(
+; CHECK-NEXT: [[Y:%.*]] = add nuw i8 [[YY:%.*]], 1
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C0:%.*]], i8 0, i8 [[Y]]
+; CHECK-NEXT: [[SELX:%.*]] = or i8 [[SEL]], [[X:%.*]]
+; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[SELX]], 1
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 0, i8 %y
+ %selx = or i8 %sel, %x
+ %r = icmp ne i8 %selx, 1
+ ret i1 %r
+}
+
+define i1 @src_fv_eq(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_fv_eq(
+; CHECK-NEXT: [[TMP1:%.*]] = xor i1 [[C0:%.*]], true
+; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i8 [[X:%.*]], 0
+; CHECK-NEXT: [[R:%.*]] = and i1 [[TMP2]], [[TMP1]]
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 %y, i8 0
+ %selx = or i8 %sel, %x
+ %r = icmp eq i8 %selx, 0
+ ret i1 %r
+}
+
+define i1 @src_fv_eq_fail_cant_invert(i1 %c0, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_fv_eq_fail_cant_invert(
+; CHECK-NEXT: [[Y:%.*]] = add nuw i8 [[YY:%.*]], 1
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C0:%.*]], i8 [[Y]], i8 0
+; CHECK-NEXT: [[SELX:%.*]] = or i8 [[SEL]], [[X:%.*]]
+; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[SELX]], 0
+; CHECK-NEXT: call void @use.i8(i8 [[SEL]])
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 %y, i8 0
+ %selx = or i8 %sel, %x
+ %r = icmp eq i8 %selx, 0
+ call void @use.i8(i8 %sel)
+ ret i1 %r
+}
+
+define i1 @src_fv_eq_fail_cant_invert2(i1 %c1, i8 %a, i8 %b, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_fv_eq_fail_cant_invert2(
+; CHECK-NEXT: [[C0:%.*]] = icmp ugt i8 [[A:%.*]], [[B:%.*]]
+; CHECK-NEXT: [[Y:%.*]] = add nuw i8 [[YY:%.*]], 1
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C0]], i8 [[Y]], i8 0
+; CHECK-NEXT: [[CC:%.*]] = or i1 [[C0]], [[C1:%.*]]
+; CHECK-NEXT: [[SEL_OTHER:%.*]] = select i1 [[CC]], i8 [[Y]], i8 [[B]]
+; CHECK-NEXT: [[SELX:%.*]] = or i8 [[SEL]], [[X:%.*]]
+; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[SELX]], 0
+; CHECK-NEXT: call void @use.i8(i8 [[SEL]])
+; CHECK-NEXT: call void @use.i8(i8 [[SEL_OTHER]])
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %c0 = icmp ugt i8 %a, %b
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 %y, i8 0
+ %cc = or i1 %c0, %c1
+ %sel_other = select i1 %cc, i8 %y, i8 %b
+
+ %selx = or i8 %sel, %x
+ %r = icmp eq i8 %selx, 0
+ call void @use.i8(i8 %sel)
+ call void @use.i8(i8 %sel_other)
+ ret i1 %r
+}
+
+define i1 @src_fv_eq_invert2(i1 %c1, i8 %a, i8 %b, i8 %x, i8 %yy) {
+; CHECK-LABEL: @src_fv_eq_invert2(
+; CHECK-NEXT: [[C0:%.*]] = icmp ugt i8 [[A:%.*]], [[B:%.*]]
+; CHECK-NEXT: [[Y:%.*]] = add nuw i8 [[YY:%.*]], 1
+; CHECK-NEXT: [[CC:%.*]] = or i1 [[C0]], [[C1:%.*]]
+; CHECK-NEXT: [[SEL_OTHER:%.*]] = select i1 [[CC]], i8 [[Y]], i8 [[B]]
+; CHECK-NEXT: [[TMP1:%.*]] = xor i1 [[C0]], true
+; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i8 [[X:%.*]], 0
+; CHECK-NEXT: [[R:%.*]] = and i1 [[TMP2]], [[TMP1]]
+; CHECK-NEXT: call void @use.i8(i8 [[SEL_OTHER]])
+; CHECK-NEXT: ret i1 [[R]]
+;
+ %c0 = icmp ugt i8 %a, %b
+ %y = add nuw i8 %yy, 1
+ %sel = select i1 %c0, i8 %y, i8 0
+ %cc = or i1 %c0, %c1
+ %sel_other = select i1 %cc, i8 %y, i8 %b
+
+ %selx = or i8 %sel, %x
+ %r = icmp eq i8 %selx, 0
+ call void @use.i8(i8 %sel_other)
+ ret i1 %r
+}
+
+
+
+
----------------
dtcxzyw wrote:
```suggestion
```
https://github.com/llvm/llvm-project/pull/88183
More information about the llvm-commits
mailing list