1; RUN: opt < %s -S -basicaa -memcpyopt | FileCheck %s 2target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64" 3 4declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i1) nounwind 5declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i1) nounwind 6 7; The resulting memset is only 4-byte aligned, despite containing 8; a 16-byte aligned store in the middle. 9 10define void @foo(i32* %p) { 11; CHECK-LABEL: @foo( 12; CHECK: call void @llvm.memset.p0i8.i64(i8* align 4 {{.*}}, i8 0, i64 16, i1 false) 13 %a0 = getelementptr i32, i32* %p, i64 0 14 store i32 0, i32* %a0, align 4 15 %a1 = getelementptr i32, i32* %p, i64 1 16 store i32 0, i32* %a1, align 16 17 %a2 = getelementptr i32, i32* %p, i64 2 18 store i32 0, i32* %a2, align 4 19 %a3 = getelementptr i32, i32* %p, i64 3 20 store i32 0, i32* %a3, align 4 21 ret void 22} 23 24; Replacing %a8 with %a4 in the memset requires boosting the alignment of %a4. 25 26define void @bar() { 27; CHECK-LABEL: @bar( 28; CHECK: %a4 = alloca i32, align 8 29; CHECK-NOT: memcpy 30 %a4 = alloca i32, align 4 31 %a8 = alloca i32, align 8 32 %a8.cast = bitcast i32* %a8 to i8* 33 %a4.cast = bitcast i32* %a4 to i8* 34 call void @llvm.memset.p0i8.i64(i8* align 8 %a8.cast, i8 0, i64 4, i1 false) 35 call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 4 %a4.cast, i8* align 4 %a8.cast, i64 4, i1 false) 36 ret void 37} 38