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1; RUN: opt -S -passes=gvn < %s | FileCheck %s2; Check that loads from calloc are recognized as being zero.3 4target 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"5 6; Function Attrs: nounwind uwtable7define i32 @test1() {8 %1 = tail call noalias ptr @calloc(i64 1, i64 4)9 ; This load is trivially constant zero10 %2 = load i32, ptr %1, align 411 ret i32 %212 13; CHECK-LABEL: @test1(14; CHECK-NOT: %2 = load i32, ptr %1, align 415; CHECK: ret i32 016 17; CHECK_NO_LIBCALLS-LABEL: @test1(18; CHECK_NO_LIBCALLS: load19; CHECK_NO_LIBCALLS: ret i32 %20 21}22 23define i32 @as_invoke(i1 %c) personality ptr undef {24bb3:25 %mem = invoke noalias ptr @calloc(i64 1, i64 4)26 to label %bb4 unwind label %bb127 28bb1:29 %lp = landingpad { ptr, i32 } cleanup30 ret i32 031 32bb4:33 ; This load is trivially constant zero34 %res = load i32, ptr %mem, align 435 ret i32 %res36 37; CHECK-LABEL: @as_invoke(38; CHECK-NOT: %3 = load i32, ptr %2, align 439; CHECK: ret i32 040 41; CHECK_NO_LIBCALLS-LABEL: @as_invoke(42; CHECK_NO_LIBCALLS: load43; CHECK_NO_LIBCALLS: ret i32 %44}45 46declare noalias ptr @calloc(i64, i64) allockind("alloc,zeroed") allocsize(0,1)47