50 lines
1.7 KiB
LLVM
50 lines
1.7 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
|
|
; RUN: opt < %s -instcombine -S | FileCheck %s
|
|
|
|
target datalayout = "p:32:32"
|
|
|
|
%S = type { [2 x i32] }
|
|
|
|
define i1 @test([0 x %S]* %p, i32 %n) {
|
|
; CHECK-LABEL: @test(
|
|
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[N:%.*]], 1
|
|
; CHECK-NEXT: ret i1 [[CMP]]
|
|
;
|
|
%start.cast = bitcast [0 x %S]* %p to %S*
|
|
%end = getelementptr inbounds [0 x %S], [0 x %S]* %p, i32 0, i32 %n, i32 0, i32 0
|
|
%end.cast = bitcast i32* %end to %S*
|
|
%last = getelementptr inbounds %S, %S* %end.cast, i32 -1
|
|
%cmp = icmp eq %S* %last, %start.cast
|
|
ret i1 %cmp
|
|
}
|
|
|
|
; Same test using 64-bit indices.
|
|
define i1 @test64([0 x %S]* %p, i64 %n) {
|
|
; CHECK-LABEL: @test64(
|
|
; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[N:%.*]] to i32
|
|
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[TMP1]], 1
|
|
; CHECK-NEXT: ret i1 [[CMP]]
|
|
;
|
|
%start.cast = bitcast [0 x %S]* %p to %S*
|
|
%end = getelementptr inbounds [0 x %S], [0 x %S]* %p, i64 0, i64 %n, i32 0, i64 0
|
|
%end.cast = bitcast i32* %end to %S*
|
|
%last = getelementptr inbounds %S, %S* %end.cast, i64 -1
|
|
%cmp = icmp eq %S* %last, %start.cast
|
|
ret i1 %cmp
|
|
}
|
|
|
|
; Here the offset overflows and is treated modulo 2^32. This is UB.
|
|
define i1 @test64_overflow([0 x %S]* %p, i64 %n) {
|
|
; CHECK-LABEL: @test64_overflow(
|
|
; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[N:%.*]] to i32
|
|
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[TMP1]], 1
|
|
; CHECK-NEXT: ret i1 [[CMP]]
|
|
;
|
|
%start.cast = bitcast [0 x %S]* %p to %S*
|
|
%end = getelementptr inbounds [0 x %S], [0 x %S]* %p, i64 0, i64 %n, i32 0, i64 8589934592
|
|
%end.cast = bitcast i32* %end to %S*
|
|
%last = getelementptr inbounds %S, %S* %end.cast, i64 -1
|
|
%cmp = icmp eq %S* %last, %start.cast
|
|
ret i1 %cmp
|
|
}
|