[llvm] 4bfd763 - [InstCombine] Add tests for (select (icmp x, Cp2_0), (binop y, Cp2_1), y); NFC

[Noah Goldstein via llvm-commits]

Author: Noah Goldstein
Date: 2023-08-16T22:43:05-05:00
New Revision: 4bfd7633765e8061a3738adac76e8c7075889d88

URL: https://github.com/llvm/llvm-project/commit/4bfd7633765e8061a3738adac76e8c7075889d88
DIFF: https://github.com/llvm/llvm-project/commit/4bfd7633765e8061a3738adac76e8c7075889d88.diff

LOG: [InstCombine] Add tests for (select (icmp x, Cp2_0), (binop y, Cp2_1), y); NFC

Differential Revision: https://reviews.llvm.org/D148411

Added: 
    

Modified: 
    llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll

Removed: 
    


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diff  --git a/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll b/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll
index 04588fd7114c40..f1f89085cb32a6 100644
--- a/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll
+++ b/llvm/test/Transforms/InstCombine/select-with-bitwise-ops.ll
@@ -771,6 +771,21 @@ define i8 @test70(i8 %x, i8 %y) {
   ret i8 %select
 }
 
+define i8 @test70_multiuse(i8 %x, i8 %y) {
+; CHECK-LABEL: @test70_multiuse(
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0
+; CHECK-NEXT:    [[OR:%.*]] = or i8 [[Y:%.*]], 2
+; CHECK-NEXT:    call void @use(i8 [[OR]])
+; CHECK-NEXT:    [[SELECT:%.*]] = select i1 [[CMP]], i8 [[OR]], i8 [[Y]]
+; CHECK-NEXT:    ret i8 [[SELECT]]
+;
+  %cmp = icmp slt i8 %x, 0
+  %or = or i8 %y, 2
+  call void @use(i8 %or)
+  %select = select i1 %cmp, i8 %or, i8 %y
+  ret i8 %select
+}
+
 define i32 @shift_no_xor_multiuse_or(i32 %x, i32 %y) {
 ; CHECK-LABEL: @shift_no_xor_multiuse_or(
 ; CHECK-NEXT:    [[OR:%.*]] = or i32 [[Y:%.*]], 2
@@ -1572,3 +1587,34 @@ define i8 @clear_bits_extra_use2(i8 %x, i1 %b)  {
   %cond = select i1 %b, i8 %and, i8 %or
   ret i8 %cond
 }
+
+; Tests factoring in cost of saving the `and`
+define i64 @xor_i8_to_i64_shl_save_and_eq(i8 %x, i64 %y) {
+; CHECK-LABEL: @xor_i8_to_i64_shl_save_and_eq(
+; CHECK-NEXT:    [[XX:%.*]] = and i8 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[XX]], 0
+; CHECK-NEXT:    [[Z:%.*]] = xor i64 [[Y:%.*]], -9223372036854775808
+; CHECK-NEXT:    [[R:%.*]] = select i1 [[CMP]], i64 [[Z]], i64 [[Y]]
+; CHECK-NEXT:    ret i64 [[R]]
+;
+  %xx = and i8 %x, 1
+  %cmp = icmp eq i8 %xx, 0
+  %z = xor i64 %y, -9223372036854775808
+  %r = select i1 %cmp, i64 %z, i64 %y
+  ret i64 %r
+}
+
+define i64 @xor_i8_to_i64_shl_save_and_ne(i8 %x, i64 %y) {
+; CHECK-LABEL: @xor_i8_to_i64_shl_save_and_ne(
+; CHECK-NEXT:    [[XX:%.*]] = and i8 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP_NOT:%.*]] = icmp eq i8 [[XX]], 0
+; CHECK-NEXT:    [[Z:%.*]] = xor i64 [[Y:%.*]], -9223372036854775808
+; CHECK-NEXT:    [[R:%.*]] = select i1 [[CMP_NOT]], i64 [[Y]], i64 [[Z]]
+; CHECK-NEXT:    ret i64 [[R]]
+;
+  %xx = and i8 %x, 1
+  %cmp = icmp ne i8 %xx, 0
+  %z = xor i64 %y, -9223372036854775808
+  %r = select i1 %cmp, i64 %z, i64 %y
+  ret i64 %r
+}