[llvm] 9c00afe - [DSE] Add test case with multiple inbounds stores, followed by OOB.

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2021-11-12T09:40:03Z
New Revision: 9c00afe926e9f22f4e0cd92d88068c8a6ed769d0

URL: https://github.com/llvm/llvm-project/commit/9c00afe926e9f22f4e0cd92d88068c8a6ed769d0
DIFF: https://github.com/llvm/llvm-project/commit/9c00afe926e9f22f4e0cd92d88068c8a6ed769d0.diff

LOG: [DSE] Add test case with multiple inbounds stores, followed by OOB.

This patch extends the existing out-of-bounds store tests with a case
with a bigger object and multiple inbounds stores, followed by an OOB
store. The OOB store is not used to remove the inbounds stores in this
case at the moment.

Added: 
    

Modified: 
    llvm/test/Transforms/DeadStoreElimination/out-of-bounds-stores.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/DeadStoreElimination/out-of-bounds-stores.ll b/llvm/test/Transforms/DeadStoreElimination/out-of-bounds-stores.ll
index 925ab4e99597d..949ab781b4961 100644
--- a/llvm/test/Transforms/DeadStoreElimination/out-of-bounds-stores.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/out-of-bounds-stores.ll
@@ -1,7 +1,7 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt -dse -S %s | FileCheck %s
 
-declare void @use(i32)
+declare void @use_pointer(i32*)
 
 ; Out-of-bounds stores can be considered killing any other stores to the same
 ; object in the same BB, because they are UB and guaranteed to execute. Note
@@ -10,9 +10,10 @@ declare void @use(i32)
 define i32 @test_out_of_bounds_store_local(i1 %c) {
 ; CHECK-LABEL: @test_out_of_bounds_store_local(
 ; CHECK-NEXT:    [[D:%.*]] = alloca [1 x i32], align 4
-; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds [1 x i32], [1 x i32]* [[D]], i64 0, i64 0
-; CHECK-NEXT:    [[LV1:%.*]] = load i32, i32* [[ARRAYIDX1]], align 4
-; CHECK-NEXT:    call void @use(i32 [[LV1]])
+; CHECK-NEXT:    [[ARRAYIDX_1:%.*]] = getelementptr inbounds [1 x i32], [1 x i32]* [[D]], i64 0, i64 1
+; CHECK-NEXT:    store i32 20, i32* [[ARRAYIDX_1]], align 4
+; CHECK-NEXT:    [[BC:%.*]] = bitcast [1 x i32]* [[D]] to i32*
+; CHECK-NEXT:    call void @use_pointer(i32* [[BC]])
 ; CHECK-NEXT:    ret i32 0
 ;
   %d = alloca [1 x i32], align 4
@@ -20,9 +21,37 @@ define i32 @test_out_of_bounds_store_local(i1 %c) {
   store i32 10, i32* %arrayidx, align 4
   %arrayidx.1 = getelementptr inbounds [1 x i32], [1 x i32]* %d, i64 0, i64 1
   store i32 20, i32* %arrayidx.1, align 4
-  %arrayidx1 = getelementptr inbounds [1 x i32], [1 x i32]* %d, i64 0, i64 0
-  %lv1 = load i32, i32* %arrayidx1, align 4
-  call void @use(i32 %lv1)
+  %bc = bitcast [1 x i32]* %d to i32*
+  call void @use_pointer(i32* %bc)
+  ret i32 0
+}
+
+; Similar to @test_out_of_bounds_store_local, but with multiple in-bounds
+; stores to a larger object, followed by an out-of-bounds store.
+; FIXME: the 2 inbounds stores could be removed by applying the same
+; reasoning as for @test_out_of_bounds_store_local.
+define i32 @test_out_of_bounds_store_local_larger_object(i1 %c) {
+; CHECK-LABEL: @test_out_of_bounds_store_local_larger_object(
+; CHECK-NEXT:    [[D:%.*]] = alloca [2 x i32], align 4
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds [2 x i32], [2 x i32]* [[D]], i64 0, i64 0
+; CHECK-NEXT:    store i32 10, i32* [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[ARRAYIDX_1:%.*]] = getelementptr inbounds [2 x i32], [2 x i32]* [[D]], i64 0, i64 1
+; CHECK-NEXT:    store i32 20, i32* [[ARRAYIDX_1]], align 4
+; CHECK-NEXT:    [[ARRAYIDX_2:%.*]] = getelementptr inbounds [2 x i32], [2 x i32]* [[D]], i64 0, i64 2
+; CHECK-NEXT:    store i32 30, i32* [[ARRAYIDX_2]], align 4
+; CHECK-NEXT:    [[BC:%.*]] = bitcast [2 x i32]* [[D]] to i32*
+; CHECK-NEXT:    call void @use_pointer(i32* [[BC]])
+; CHECK-NEXT:    ret i32 0
+;
+  %d = alloca [2 x i32], align 4
+  %arrayidx = getelementptr inbounds [2 x i32], [2 x i32]* %d, i64 0, i64 0
+  store i32 10, i32* %arrayidx, align 4
+  %arrayidx.1 = getelementptr inbounds [2 x i32], [2 x i32]* %d, i64 0, i64 1
+  store i32 20, i32* %arrayidx.1, align 4
+  %arrayidx.2 = getelementptr inbounds [2 x i32], [2 x i32]* %d, i64 0, i64 2
+  store i32 30, i32* %arrayidx.2, align 4
+  %bc = bitcast [2 x i32]* %d to i32*
+  call void @use_pointer(i32* %bc)
   ret i32 0
 }
 
@@ -44,9 +73,8 @@ define i32 @test_out_of_bounds_store_nonlocal(i1 %c) {
 ; CHECK:       for.body.1:
 ; CHECK-NEXT:    ret i32 1
 ; CHECK:       for.end:
-; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds [1 x i32], [1 x i32]* [[D]], i64 0, i64 0
-; CHECK-NEXT:    [[LV1:%.*]] = load i32, i32* [[ARRAYIDX1]], align 4
-; CHECK-NEXT:    call void @use(i32 [[LV1]])
+; CHECK-NEXT:    [[BC:%.*]] = bitcast [1 x i32]* [[D]] to i32*
+; CHECK-NEXT:    call void @use_pointer(i32* [[BC]])
 ; CHECK-NEXT:    ret i32 0
 ;
   %d = alloca [1 x i32], align 4
@@ -66,8 +94,7 @@ for.body.1:                                       ; preds = %for.inc
   ret i32 1
 
 for.end:                                          ; preds = %for.inc
-  %arrayidx1 = getelementptr inbounds [1 x i32], [1 x i32]* %d, i64 0, i64 0
-  %lv1 = load i32, i32* %arrayidx1, align 4
-  call void @use(i32 %lv1)
+  %bc = bitcast [1 x i32]* %d to i32*
+  call void @use_pointer(i32* %bc)
   ret i32 0
 }