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| ; RUN: opt < %s -inferattrs -S | FileCheck %s
; RUN: opt < %s -attributor --attributor-disable=false -S | FileCheck %s --check-prefix=ATTRIBUTOR
; Determine dereference-ability before unused loads get deleted:
; https://bugs.llvm.org/show_bug.cgi?id=21780
define <4 x double> @PR21780(double* %ptr) {
; CHECK-LABEL: @PR21780(double* %ptr)
; FIXME: this should be @PR21780(double* nonnull dereferenceable(32) %ptr)
; trakcing use of GEP in Attributor would fix this problem.
; ATTRIBUTOR-LABEL: @PR21780(double* nocapture nonnull readonly dereferenceable(8) %ptr)
; GEP of index 0 is simplified away.
%arrayidx1 = getelementptr inbounds double, double* %ptr, i64 1
%arrayidx2 = getelementptr inbounds double, double* %ptr, i64 2
%arrayidx3 = getelementptr inbounds double, double* %ptr, i64 3
%t0 = load double, double* %ptr, align 8
%t1 = load double, double* %arrayidx1, align 8
%t2 = load double, double* %arrayidx2, align 8
%t3 = load double, double* %arrayidx3, align 8
%vecinit0 = insertelement <4 x double> undef, double %t0, i32 0
%vecinit1 = insertelement <4 x double> %vecinit0, double %t1, i32 1
%vecinit2 = insertelement <4 x double> %vecinit1, double %t2, i32 2
%vecinit3 = insertelement <4 x double> %vecinit2, double %t3, i32 3
%shuffle = shufflevector <4 x double> %vecinit3, <4 x double> %vecinit3, <4 x i32> <i32 0, i32 0, i32 2, i32 2>
ret <4 x double> %shuffle
}
define double @PR21780_only_access3_with_inbounds(double* %ptr) {
; CHECK-LABEL: @PR21780_only_access3_with_inbounds(double* %ptr)
; FIXME: this should be @PR21780_only_access3_with_inbounds(double* nonnull dereferenceable(32) %ptr)
; trakcing use of GEP in Attributor would fix this problem.
; ATTRIBUTOR-LABEL: @PR21780_only_access3_with_inbounds(double* nocapture readonly %ptr)
%arrayidx3 = getelementptr inbounds double, double* %ptr, i64 3
%t3 = load double, double* %arrayidx3, align 8
ret double %t3
}
define double @PR21780_only_access3_without_inbounds(double* %ptr) {
; CHECK-LABEL: @PR21780_only_access3_without_inbounds(double* %ptr)
; ATTRIBUTOR-LABEL: @PR21780_only_access3_without_inbounds(double* nocapture readonly %ptr)
%arrayidx3 = getelementptr double, double* %ptr, i64 3
%t3 = load double, double* %arrayidx3, align 8
ret double %t3
}
define double @PR21780_without_inbounds(double* %ptr) {
; CHECK-LABEL: @PR21780_without_inbounds(double* %ptr)
; FIXME: this should be @PR21780_without_inbounds(double* nonnull dereferenceable(32) %ptr)
; ATTRIBUTOR-LABEL: @PR21780_without_inbounds(double* nocapture nonnull readonly dereferenceable(8) %ptr)
%arrayidx1 = getelementptr double, double* %ptr, i64 1
%arrayidx2 = getelementptr double, double* %ptr, i64 2
%arrayidx3 = getelementptr double, double* %ptr, i64 3
%t0 = load double, double* %ptr, align 8
%t1 = load double, double* %arrayidx1, align 8
%t2 = load double, double* %arrayidx2, align 8
%t3 = load double, double* %arrayidx3, align 8
ret double %t3
}
; Unsimplified, but still valid. Also, throw in some bogus arguments.
define void @gep0(i8* %unused, i8* %other, i8* %ptr) {
; CHECK-LABEL: @gep0(i8* %unused, i8* %other, i8* %ptr)
%arrayidx0 = getelementptr i8, i8* %ptr, i64 0
%arrayidx1 = getelementptr i8, i8* %ptr, i64 1
%arrayidx2 = getelementptr i8, i8* %ptr, i64 2
%t0 = load i8, i8* %arrayidx0
%t1 = load i8, i8* %arrayidx1
%t2 = load i8, i8* %arrayidx2
store i8 %t2, i8* %other
ret void
}
; Order of accesses does not change computation.
; Multiple arguments may be dereferenceable.
define void @ordering(i8* %ptr1, i32* %ptr2) {
; CHECK-LABEL: @ordering(i8* %ptr1, i32* %ptr2)
%a20 = getelementptr i32, i32* %ptr2, i64 0
%a12 = getelementptr i8, i8* %ptr1, i64 2
%t12 = load i8, i8* %a12
%a11 = getelementptr i8, i8* %ptr1, i64 1
%t20 = load i32, i32* %a20
%a10 = getelementptr i8, i8* %ptr1, i64 0
%t10 = load i8, i8* %a10
%t11 = load i8, i8* %a11
%a21 = getelementptr i32, i32* %ptr2, i64 1
%t21 = load i32, i32* %a21
ret void
}
; Not in entry block.
define void @not_entry_but_guaranteed_to_execute(i8* %ptr) {
; CHECK-LABEL: @not_entry_but_guaranteed_to_execute(i8* %ptr)
entry:
br label %exit
exit:
%arrayidx0 = getelementptr i8, i8* %ptr, i64 0
%arrayidx1 = getelementptr i8, i8* %ptr, i64 1
%arrayidx2 = getelementptr i8, i8* %ptr, i64 2
%t0 = load i8, i8* %arrayidx0
%t1 = load i8, i8* %arrayidx1
%t2 = load i8, i8* %arrayidx2
ret void
}
; Not in entry block and not guaranteed to execute.
define void @not_entry_not_guaranteed_to_execute(i8* %ptr, i1 %cond) {
; CHECK-LABEL: @not_entry_not_guaranteed_to_execute(i8* %ptr, i1 %cond)
entry:
br i1 %cond, label %loads, label %exit
loads:
%arrayidx0 = getelementptr i8, i8* %ptr, i64 0
%arrayidx1 = getelementptr i8, i8* %ptr, i64 1
%arrayidx2 = getelementptr i8, i8* %ptr, i64 2
%t0 = load i8, i8* %arrayidx0
%t1 = load i8, i8* %arrayidx1
%t2 = load i8, i8* %arrayidx2
ret void
exit:
ret void
}
; The last load may not execute, so derefenceable bytes only covers the 1st two loads.
define void @partial_in_entry(i16* %ptr, i1 %cond) {
; CHECK-LABEL: @partial_in_entry(i16* %ptr, i1 %cond)
entry:
%arrayidx0 = getelementptr i16, i16* %ptr, i64 0
%arrayidx1 = getelementptr i16, i16* %ptr, i64 1
%arrayidx2 = getelementptr i16, i16* %ptr, i64 2
%t0 = load i16, i16* %arrayidx0
%t1 = load i16, i16* %arrayidx1
br i1 %cond, label %loads, label %exit
loads:
%t2 = load i16, i16* %arrayidx2
ret void
exit:
ret void
}
; The volatile load can't be used to prove a non-volatile access is allowed.
; The 2nd and 3rd loads may never execute.
define void @volatile_is_not_dereferenceable(i16* %ptr) {
; CHECK-LABEL: @volatile_is_not_dereferenceable(i16* %ptr)
%arrayidx0 = getelementptr i16, i16* %ptr, i64 0
%arrayidx1 = getelementptr i16, i16* %ptr, i64 1
%arrayidx2 = getelementptr i16, i16* %ptr, i64 2
%t0 = load volatile i16, i16* %arrayidx0
%t1 = load i16, i16* %arrayidx1
%t2 = load i16, i16* %arrayidx2
ret void
}
declare void @may_not_return()
define void @not_guaranteed_to_transfer_execution(i16* %ptr) {
; CHECK-LABEL: @not_guaranteed_to_transfer_execution(i16* %ptr)
%arrayidx0 = getelementptr i16, i16* %ptr, i64 0
%arrayidx1 = getelementptr i16, i16* %ptr, i64 1
%arrayidx2 = getelementptr i16, i16* %ptr, i64 2
%t0 = load i16, i16* %arrayidx0
call void @may_not_return()
%t1 = load i16, i16* %arrayidx1
%t2 = load i16, i16* %arrayidx2
ret void
}
; We must have consecutive accesses.
define void @variable_gep_index(i8* %unused, i8* %ptr, i64 %variable_index) {
; CHECK-LABEL: @variable_gep_index(i8* %unused, i8* %ptr, i64 %variable_index)
%arrayidx1 = getelementptr i8, i8* %ptr, i64 %variable_index
%arrayidx2 = getelementptr i8, i8* %ptr, i64 2
%t0 = load i8, i8* %ptr
%t1 = load i8, i8* %arrayidx1
%t2 = load i8, i8* %arrayidx2
ret void
}
; Deal with >1 GEP index.
define void @multi_index_gep(<4 x i8>* %ptr) {
; CHECK-LABEL: @multi_index_gep(<4 x i8>* %ptr)
%arrayidx00 = getelementptr <4 x i8>, <4 x i8>* %ptr, i64 0, i64 0
%t0 = load i8, i8* %arrayidx00
ret void
}
; Could round weird bitwidths down?
define void @not_byte_multiple(i9* %ptr) {
; CHECK-LABEL: @not_byte_multiple(i9* %ptr)
%arrayidx0 = getelementptr i9, i9* %ptr, i64 0
%t0 = load i9, i9* %arrayidx0
ret void
}
; Missing direct access from the pointer.
define void @no_pointer_deref(i16* %ptr) {
; CHECK-LABEL: @no_pointer_deref(i16* %ptr)
%arrayidx1 = getelementptr i16, i16* %ptr, i64 1
%arrayidx2 = getelementptr i16, i16* %ptr, i64 2
%t1 = load i16, i16* %arrayidx1
%t2 = load i16, i16* %arrayidx2
ret void
}
; Out-of-order is ok, but missing access concludes dereferenceable range.
define void @non_consecutive(i32* %ptr) {
; CHECK-LABEL: @non_consecutive(i32* %ptr)
%arrayidx1 = getelementptr i32, i32* %ptr, i64 1
%arrayidx0 = getelementptr i32, i32* %ptr, i64 0
%arrayidx3 = getelementptr i32, i32* %ptr, i64 3
%t1 = load i32, i32* %arrayidx1
%t0 = load i32, i32* %arrayidx0
%t3 = load i32, i32* %arrayidx3
ret void
}
; Improve on existing dereferenceable attribute.
define void @more_bytes(i32* dereferenceable(8) %ptr) {
; CHECK-LABEL: @more_bytes(i32* dereferenceable(8) %ptr)
%arrayidx3 = getelementptr i32, i32* %ptr, i64 3
%arrayidx1 = getelementptr i32, i32* %ptr, i64 1
%arrayidx0 = getelementptr i32, i32* %ptr, i64 0
%arrayidx2 = getelementptr i32, i32* %ptr, i64 2
%t3 = load i32, i32* %arrayidx3
%t1 = load i32, i32* %arrayidx1
%t2 = load i32, i32* %arrayidx2
%t0 = load i32, i32* %arrayidx0
ret void
}
; But don't pessimize existing dereferenceable attribute.
define void @better_bytes(i32* dereferenceable(100) %ptr) {
; CHECK-LABEL: @better_bytes(i32* dereferenceable(100) %ptr)
%arrayidx3 = getelementptr i32, i32* %ptr, i64 3
%arrayidx1 = getelementptr i32, i32* %ptr, i64 1
%arrayidx0 = getelementptr i32, i32* %ptr, i64 0
%arrayidx2 = getelementptr i32, i32* %ptr, i64 2
%t3 = load i32, i32* %arrayidx3
%t1 = load i32, i32* %arrayidx1
%t2 = load i32, i32* %arrayidx2
%t0 = load i32, i32* %arrayidx0
ret void
}
define void @bitcast(i32* %arg) {
; CHECK-LABEL: @bitcast(i32* %arg)
%ptr = bitcast i32* %arg to float*
%arrayidx0 = getelementptr float, float* %ptr, i64 0
%arrayidx1 = getelementptr float, float* %ptr, i64 1
%t0 = load float, float* %arrayidx0
%t1 = load float, float* %arrayidx1
ret void
}
define void @bitcast_different_sizes(double* %arg1, i8* %arg2) {
; CHECK-LABEL: @bitcast_different_sizes(double* %arg1, i8* %arg2)
%ptr1 = bitcast double* %arg1 to float*
%a10 = getelementptr float, float* %ptr1, i64 0
%a11 = getelementptr float, float* %ptr1, i64 1
%a12 = getelementptr float, float* %ptr1, i64 2
%ld10 = load float, float* %a10
%ld11 = load float, float* %a11
%ld12 = load float, float* %a12
%ptr2 = bitcast i8* %arg2 to i64*
%a20 = getelementptr i64, i64* %ptr2, i64 0
%a21 = getelementptr i64, i64* %ptr2, i64 1
%ld20 = load i64, i64* %a20
%ld21 = load i64, i64* %a21
ret void
}
define void @negative_offset(i32* %arg) {
; CHECK-LABEL: @negative_offset(i32* %arg)
%ptr = bitcast i32* %arg to float*
%arrayidx0 = getelementptr float, float* %ptr, i64 0
%arrayidx1 = getelementptr float, float* %ptr, i64 -1
%t0 = load float, float* %arrayidx0
%t1 = load float, float* %arrayidx1
ret void
}
define void @stores(i32* %arg) {
; CHECK-LABEL: @stores(i32* %arg)
%ptr = bitcast i32* %arg to float*
%arrayidx0 = getelementptr float, float* %ptr, i64 0
%arrayidx1 = getelementptr float, float* %ptr, i64 1
store float 1.0, float* %arrayidx0
store float 2.0, float* %arrayidx1
ret void
}
define void @load_store(i32* %arg) {
; CHECK-LABEL: @load_store(i32* %arg)
%ptr = bitcast i32* %arg to float*
%arrayidx0 = getelementptr float, float* %ptr, i64 0
%arrayidx1 = getelementptr float, float* %ptr, i64 1
%t1 = load float, float* %arrayidx0
store float 2.0, float* %arrayidx1
ret void
}
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