@e = common global %structTy zeroinitializer, align 4
-; CHECK-LABEL: f
-define void @f() {
-entry:
+;; Ensure that MergeConsecutiveStores doesn't incorrectly reorder
+;; store operations. The first test stores in increasing address
+;; order, the second in decreasing -- but in both cases should have
+;; the same result in memory in the end.
-; CHECK: movabsq $528280977409, %rax
+; CHECK-LABEL: redundant_stores_merging:
+; CHECK: movl $123, e+8(%rip)
+; CHECK: movabsq $1958505086977, %rax
; CHECK: movq %rax, e+4(%rip)
-; CHECK: movl $456, e+8(%rip)
-
+define void @redundant_stores_merging() {
+entry:
store i32 1, i32* getelementptr inbounds (%structTy, %structTy* @e, i64 0, i32 1), align 4
store i32 123, i32* getelementptr inbounds (%structTy, %structTy* @e, i64 0, i32 2), align 4
store i32 456, i32* getelementptr inbounds (%structTy, %structTy* @e, i64 0, i32 2), align 4
ret void
}
+;; This variant tests PR25154.
+; CHECK-LABEL: redundant_stores_merging_reverse:
+; CHECK: movl $123, e+8(%rip)
+; CHECK: movabsq $1958505086977, %rax
+; CHECK: movq %rax, e+4(%rip)
+define void @redundant_stores_merging_reverse() {
+entry:
+ store i32 123, i32* getelementptr inbounds (%structTy, %structTy* @e, i64 0, i32 2), align 4
+ store i32 456, i32* getelementptr inbounds (%structTy, %structTy* @e, i64 0, i32 2), align 4
+ store i32 1, i32* getelementptr inbounds (%structTy, %structTy* @e, i64 0, i32 1), align 4
+ ret void
+}
+
+@b = common global [8 x i8] zeroinitializer, align 2
+
+;; The 2-byte store to offset 3 overlaps the 2-byte store to offset 2;
+;; these must not be reordered in MergeConsecutiveStores such that the
+;; store to 3 comes first (e.g. by merging the stores to 0 and 2 into
+;; a movl, after the store to 3).
+
+;; CHECK-LABEL: overlapping_stores_merging:
+;; CHECK: movw $0, b+2(%rip)
+;; CHECK: movw $2, b+3(%rip)
+;; CHECK: movw $1, b(%rip)
+define void @overlapping_stores_merging() {
+entry:
+ store i16 0, i16* bitcast (i8* getelementptr inbounds ([8 x i8], [8 x i8]* @b, i64 0, i64 2) to i16*), align 2
+ store i16 2, i16* bitcast (i8* getelementptr inbounds ([8 x i8], [8 x i8]* @b, i64 0, i64 3) to i16*), align 1
+ store i16 1, i16* bitcast (i8* getelementptr inbounds ([8 x i8], [8 x i8]* @b, i64 0, i64 0) to i16*), align 2
+ ret void
+}