1 ; RUN: opt -S -basicaa -gvn < %s | FileCheck %s 2 ; RUN: opt -S -basicaa -gvn -disable-simplify-libcalls < %s | FileCheck %s -check-prefix=CHECK_NO_LIBCALLS 3 ; Check that loads from calloc are recognized as being zero. 4 5 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" 6 7 ; Function Attrs: nounwind uwtable 8 define i32 @test1() { 9 %1 = tail call noalias i8* @calloc(i64 1, i64 4) 10 %2 = bitcast i8* %1 to i32* 11 ; This load is trivially constant zero 12 %3 = load i32, i32* %2, align 4 13 ret i32 %3 14 15 ; CHECK-LABEL: @test1( 16 ; CHECK-NOT: %3 = load i32, i32* %2, align 4 17 ; CHECK: ret i32 0 18 19 ; CHECK_NO_LIBCALLS-LABEL: @test1( 20 ; CHECK_NO_LIBCALLS: load 21 ; CHECK_NO_LIBCALLS: ret i32 % 22 23 } 24 25 declare noalias i8* @calloc(i64, i64) 26
