; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=mem2reg -S | FileCheck %s
; This tests that mem2reg preserves the !nonnull metadata on loads
; from allocas that get optimized out.
; Check the case where the alloca in question has a single store.
define ptr @single_store_noundef(ptr %arg) {
; CHECK-LABEL: @single_store_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8
; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr [[ARG_LOAD]], null
; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]])
; CHECK-NEXT: ret ptr [[ARG_LOAD]]
;
entry:
%buf = alloca ptr
%arg.load = load ptr, ptr %arg, align 8
store ptr %arg.load, ptr %buf, align 8
%buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0
ret ptr %buf.load
}
define ptr @single_store_missing_noundef(ptr %arg) {
; CHECK-LABEL: @single_store_missing_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8
; CHECK-NEXT: ret ptr [[ARG_LOAD]]
;
entry:
%buf = alloca ptr
%arg.load = load ptr, ptr %arg, align 8
store ptr %arg.load, ptr %buf, align 8
%buf.load = load ptr, ptr %buf, !nonnull !0
ret ptr %buf.load
}
; Check the case where the alloca in question has more than one
; store but still within one basic block.
define ptr @single_block_noundef(ptr %arg) {
; CHECK-LABEL: @single_block_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8
; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr [[ARG_LOAD]], null
; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]])
; CHECK-NEXT: ret ptr [[ARG_LOAD]]
;
entry:
%buf = alloca ptr
%arg.load = load ptr, ptr %arg, align 8
store ptr null, ptr %buf, align 8
store ptr %arg.load, ptr %buf, align 8
%buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0
ret ptr %buf.load
}
define ptr @single_block_missing_noundef(ptr %arg) {
; CHECK-LABEL: @single_block_missing_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8
; CHECK-NEXT: ret ptr [[ARG_LOAD]]
;
entry:
%buf = alloca ptr
%arg.load = load ptr, ptr %arg, align 8
store ptr null, ptr %buf, align 8
store ptr %arg.load, ptr %buf, align 8
%buf.load = load ptr, ptr %buf, !nonnull !0
ret ptr %buf.load
}
; Check the case where the alloca in question has more than one
; store and also reads ands writes in multiple blocks.
define ptr @multi_block_noundef(ptr %arg) {
; CHECK-LABEL: @multi_block_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8
; CHECK-NEXT: br label [[NEXT:%.*]]
; CHECK: next:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr [[ARG_LOAD]], null
; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]])
; CHECK-NEXT: ret ptr [[ARG_LOAD]]
;
entry:
%buf = alloca ptr
%arg.load = load ptr, ptr %arg, align 8
store ptr null, ptr %buf, align 8
br label %next
next:
store ptr %arg.load, ptr %buf, align 8
%buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0
ret ptr %buf.load
}
define ptr @multi_block_missing_noundef(ptr %arg) {
; CHECK-LABEL: @multi_block_missing_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8
; CHECK-NEXT: br label [[NEXT:%.*]]
; CHECK: next:
; CHECK-NEXT: ret ptr [[ARG_LOAD]]
;
entry:
%buf = alloca ptr
%arg.load = load ptr, ptr %arg, align 8
store ptr null, ptr %buf, align 8
br label %next
next:
store ptr %arg.load, ptr %buf, align 8
%buf.load = load ptr, ptr %buf, !nonnull !0
ret ptr %buf.load
}
; Check that we don't add an assume if it's not
; necessary i.e. the value is already implied to be nonnull
define ptr @no_assume(ptr %arg) {
; CHECK-LABEL: @no_assume(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8
; CHECK-NEXT: [[CN:%.*]] = icmp ne ptr [[ARG_LOAD]], null
; CHECK-NEXT: br i1 [[CN]], label [[NEXT:%.*]], label [[FIN:%.*]]
; CHECK: next:
; CHECK-NEXT: ret ptr [[ARG_LOAD]]
; CHECK: fin:
; CHECK-NEXT: ret ptr null
;
entry:
%buf = alloca ptr
%arg.load = load ptr, ptr %arg, align 8
%cn = icmp ne ptr %arg.load, null
br i1 %cn, label %next, label %fin
next:
; At this point the above nonnull check ensures that
; the value %arg.load is nonnull in this block and thus
; we need not add the assume.
store ptr %arg.load, ptr %buf, align 8
%buf.load = load ptr, ptr %buf, !nonnull !0
ret ptr %buf.load
fin:
ret ptr null
}
define ptr @no_store_single_load_noundef() {
; CHECK-LABEL: @no_store_single_load_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: store i1 true, ptr poison, align 1
; CHECK-NEXT: ret ptr undef
;
entry:
%buf = alloca ptr
%buf.load = load ptr, ptr %buf, !noundef !0
ret ptr %buf.load
}
define ptr @no_store_multiple_loads_noundef(i1 %c) {
; CHECK-LABEL: @no_store_multiple_loads_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: store i1 true, ptr poison, align 1
; CHECK-NEXT: ret ptr undef
; CHECK: else:
; CHECK-NEXT: store i1 true, ptr poison, align 1
; CHECK-NEXT: ret ptr undef
;
entry:
%buf = alloca ptr
br i1 %c, label %if, label %else
if:
%buf.load = load ptr, ptr %buf, !noundef !0
ret ptr %buf.load
else:
%buf.load2 = load ptr, ptr %buf, !noundef !0
ret ptr %buf.load2
}
define ptr @no_store_single_load_nonnull_noundef() {
; CHECK-LABEL: @no_store_single_load_nonnull_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: store i1 true, ptr poison, align 1
; CHECK-NEXT: ret ptr undef
;
entry:
%buf = alloca ptr
%buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0
ret ptr %buf.load
}
define ptr @no_store_multiple_loads_nonnull_noundef(i1 %c) {
; CHECK-LABEL: @no_store_multiple_loads_nonnull_noundef(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: store i1 true, ptr poison, align 1
; CHECK-NEXT: ret ptr undef
; CHECK: else:
; CHECK-NEXT: store i1 true, ptr poison, align 1
; CHECK-NEXT: ret ptr undef
;
entry:
%buf = alloca ptr
br i1 %c, label %if, label %else
if:
%buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0
ret ptr %buf.load
else:
%buf.load2 = load ptr, ptr %buf, !nonnull !0, !noundef !0
ret ptr %buf.load2
}
!0 = !{}
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