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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
; PR1201
define i32 @main(i32 %argc, i8** %argv) {
; CHECK-LABEL: @main(
; CHECK-NEXT: ret i32 0
;
%c_19 = alloca i8*
%malloc_206 = tail call i8* @malloc(i32 mul (i32 ptrtoint (i8* getelementptr (i8, i8* null, i32 1) to i32), i32 10))
store i8* %malloc_206, i8** %c_19
%tmp_207 = load i8*, i8** %c_19
tail call void @free(i8* %tmp_207)
ret i32 0
}
define i32 @dead_aligned_alloc(i32 %size, i32 %alignment, i8 %value) {
; CHECK-LABEL: @dead_aligned_alloc(
; CHECK-NEXT: ret i32 0
;
%aligned_allocation = tail call i8* @aligned_alloc(i32 %alignment, i32 %size)
store i8 %value, i8* %aligned_allocation
tail call void @free(i8* %aligned_allocation)
ret i32 0
}
declare noalias i8* @calloc(i32, i32) nounwind
declare noalias i8* @malloc(i32)
declare noalias i8* @aligned_alloc(i32, i32)
declare void @free(i8*)
define i1 @foo() {
; CHECK-LABEL: @foo(
; CHECK-NEXT: ret i1 false
;
%m = call i8* @malloc(i32 1)
%z = icmp eq i8* %m, null
call void @free(i8* %m)
ret i1 %z
}
declare void @llvm.lifetime.start.p0i8(i64, i8*)
declare void @llvm.lifetime.end.p0i8(i64, i8*)
declare i64 @llvm.objectsize.i64(i8*, i1)
declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i1) nounwind
declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i1) nounwind
declare void @llvm.memset.p0i8.i32(i8*, i8, i32, i1) nounwind
define void @test3(i8* %src) {
; CHECK-LABEL: @test3(
; CHECK-NEXT: ret void
;
%a = call noalias i8* @malloc(i32 10)
call void @llvm.lifetime.start.p0i8(i64 10, i8* %a)
call void @llvm.lifetime.end.p0i8(i64 10, i8* %a)
%size = call i64 @llvm.objectsize.i64(i8* %a, i1 true)
store i8 42, i8* %a
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %a, i8* %src, i32 32, i1 false)
call void @llvm.memmove.p0i8.p0i8.i32(i8* %a, i8* %src, i32 32, i1 false)
call void @llvm.memset.p0i8.i32(i8* %a, i8 5, i32 32, i1 false)
%alloc2 = call noalias i8* @calloc(i32 5, i32 7) nounwind
%z = icmp ne i8* %alloc2, null
ret void
}
;; This used to crash.
define void @test4() {
; CHECK-LABEL: @test4(
; CHECK-NEXT: ret void
;
%A = call i8* @malloc(i32 16000)
%B = bitcast i8* %A to double*
%C = bitcast double* %B to i8*
call void @free(i8* %C)
ret void
}
define void @test5(i8* %ptr, i8** %esc) {
; CHECK-LABEL: @test5(
; CHECK-NEXT: [[A:%.*]] = call dereferenceable_or_null(700) i8* @malloc(i32 700)
; CHECK-NEXT: [[B:%.*]] = call dereferenceable_or_null(700) i8* @malloc(i32 700)
; CHECK-NEXT: [[C:%.*]] = call dereferenceable_or_null(700) i8* @malloc(i32 700)
; CHECK-NEXT: [[D:%.*]] = call dereferenceable_or_null(700) i8* @malloc(i32 700)
; CHECK-NEXT: [[E:%.*]] = call dereferenceable_or_null(700) i8* @malloc(i32 700)
; CHECK-NEXT: [[F:%.*]] = call dereferenceable_or_null(700) i8* @malloc(i32 700)
; CHECK-NEXT: [[G:%.*]] = call dereferenceable_or_null(700) i8* @malloc(i32 700)
; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32(i8* noundef nonnull align 1 dereferenceable(32) [[PTR:%.*]], i8* noundef nonnull align 1 dereferenceable(32) [[A]], i32 32, i1 false)
; CHECK-NEXT: call void @llvm.memmove.p0i8.p0i8.i32(i8* noundef nonnull align 1 dereferenceable(32) [[PTR]], i8* noundef nonnull align 1 dereferenceable(32) [[B]], i32 32, i1 false)
; CHECK-NEXT: store i8* [[C]], i8** [[ESC:%.*]], align 8
; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32(i8* [[D]], i8* [[PTR]], i32 32, i1 true)
; CHECK-NEXT: call void @llvm.memmove.p0i8.p0i8.i32(i8* [[E]], i8* [[PTR]], i32 32, i1 true)
; CHECK-NEXT: call void @llvm.memset.p0i8.i32(i8* [[F]], i8 5, i32 32, i1 true)
; CHECK-NEXT: store volatile i8 4, i8* [[G]], align 1
; CHECK-NEXT: ret void
;
%a = call i8* @malloc(i32 700)
%b = call i8* @malloc(i32 700)
%c = call i8* @malloc(i32 700)
%d = call i8* @malloc(i32 700)
%e = call i8* @malloc(i32 700)
%f = call i8* @malloc(i32 700)
%g = call i8* @malloc(i32 700)
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %ptr, i8* %a, i32 32, i1 false)
call void @llvm.memmove.p0i8.p0i8.i32(i8* %ptr, i8* %b, i32 32, i1 false)
store i8* %c, i8** %esc
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %d, i8* %ptr, i32 32, i1 true)
call void @llvm.memmove.p0i8.p0i8.i32(i8* %e, i8* %ptr, i32 32, i1 true)
call void @llvm.memset.p0i8.i32(i8* %f, i8 5, i32 32, i1 true)
store volatile i8 4, i8* %g
ret void
}
;; When a basic block contains only a call to free and this block is accessed
;; through a test of the argument of free against null, move the call in the
;; predecessor block.
;; Using simplifycfg will remove the empty basic block and the branch operation
;; Then, performing a dead elimination will remove the comparison.
;; This is what happens with -O1 and upper.
define void @test6(i8* %foo) minsize {
; CHECK-LABEL: @test6(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TOBOOL:%.*]] = icmp eq i8* [[FOO:%.*]], null
; CHECK-NEXT: tail call void @free(i8* [[FOO]])
; CHECK-NEXT: br i1 [[TOBOOL]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
; CHECK: if.then:
; CHECK-NEXT: br label [[IF_END]]
; CHECK: if.end:
; CHECK-NEXT: ret void
;
;; Call to free moved
;; Block is now empty and may be simplified by simplifycfg
entry:
%tobool = icmp eq i8* %foo, null
br i1 %tobool, label %if.end, label %if.then
if.then: ; preds = %entry
tail call void @free(i8* %foo)
br label %if.end
if.end: ; preds = %entry, %if.then
ret void
}
;; Check that the optimization that moves a call to free in its predecessor
;; block (see test6) also happens when noop casts are involved.
define void @test12(i32* %foo) minsize {
; CHECK-LABEL: @test12(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TOBOOL:%.*]] = icmp eq i32* [[FOO:%.*]], null
; CHECK-NEXT: [[BITCAST:%.*]] = bitcast i32* [[FOO]] to i8*
; CHECK-NEXT: tail call void @free(i8* [[BITCAST]])
; CHECK-NEXT: br i1 [[TOBOOL]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
; CHECK: if.then:
; CHECK-NEXT: br label [[IF_END]]
; CHECK: if.end:
; CHECK-NEXT: ret void
;
;; Everything before the call to free should have been moved as well.
;; Call to free moved
;; Block is now empty and may be simplified by simplifycfg
entry:
%tobool = icmp eq i32* %foo, null
br i1 %tobool, label %if.end, label %if.then
if.then: ; preds = %entry
%bitcast = bitcast i32* %foo to i8*
tail call void @free(i8* %bitcast)
br label %if.end
if.end: ; preds = %entry, %if.then
ret void
}
;; Test that nonnull-implying attributes on the parameter are adjusted when the
;; call is moved, since they may no longer be valid and result in miscompiles if
;; kept unchanged.
define void @test_nonnull_free_move(i8* %foo) minsize {
; CHECK-LABEL: @test_nonnull_free_move(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TOBOOL:%.*]] = icmp eq i8* [[FOO:%.*]], null
; CHECK-NEXT: tail call void @free(i8* [[FOO]])
; CHECK-NEXT: br i1 [[TOBOOL]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
; CHECK: if.then:
; CHECK-NEXT: br label [[IF_END]]
; CHECK: if.end:
; CHECK-NEXT: ret void
;
entry:
%tobool = icmp eq i8* %foo, null
br i1 %tobool, label %if.end, label %if.then
if.then: ; preds = %entry
tail call void @free(i8* nonnull %foo)
br label %if.end
if.end: ; preds = %entry, %if.then
ret void
}
define void @test_dereferenceable_free_move(i8* %foo) minsize {
; CHECK-LABEL: @test_dereferenceable_free_move(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TOBOOL:%.*]] = icmp eq i8* [[FOO:%.*]], null
; CHECK-NEXT: tail call void @free(i8* dereferenceable_or_null(4) [[FOO]])
; CHECK-NEXT: br i1 [[TOBOOL]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
; CHECK: if.then:
; CHECK-NEXT: br label [[IF_END]]
; CHECK: if.end:
; CHECK-NEXT: ret void
;
entry:
%tobool = icmp eq i8* %foo, null
br i1 %tobool, label %if.end, label %if.then
if.then: ; preds = %entry
tail call void @free(i8* dereferenceable(4) %foo)
br label %if.end
if.end: ; preds = %entry, %if.then
ret void
}
define void @test_nonnull_dereferenceable_free_move(i8* %foo) minsize {
; CHECK-LABEL: @test_nonnull_dereferenceable_free_move(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TOBOOL:%.*]] = icmp eq i8* [[FOO:%.*]], null
; CHECK-NEXT: tail call void @free(i8* dereferenceable_or_null(16) [[FOO]])
; CHECK-NEXT: br i1 [[TOBOOL]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
; CHECK: if.then:
; CHECK-NEXT: br label [[IF_END]]
; CHECK: if.end:
; CHECK-NEXT: ret void
;
entry:
%tobool = icmp eq i8* %foo, null
br i1 %tobool, label %if.end, label %if.then
if.then: ; preds = %entry
tail call void @free(i8* nonnull dereferenceable(16) %foo)
br label %if.end
if.end: ; preds = %entry, %if.then
ret void
}
; The next four tests cover the semantics of the nofree attributes. These
; are thought to be legal transforms, but an implementation thereof has
; been reverted once due to difficult to isolate fallout.
; TODO: Freeing a no-free pointer -> %foo must be null
define void @test13(i8* nofree %foo) {
; CHECK-LABEL: @test13(
; CHECK-NEXT: call void @free(i8* [[FOO:%.*]])
; CHECK-NEXT: ret void
;
call void @free(i8* %foo)
ret void
}
; TODO: Freeing a no-free pointer -> %foo must be null
define void @test14(i8* %foo) nofree {
; CHECK-LABEL: @test14(
; CHECK-NEXT: call void @free(i8* [[FOO:%.*]])
; CHECK-NEXT: ret void
;
call void @free(i8* %foo)
ret void
}
; TODO: free call marked no-free -> %foo must be null
define void @test15(i8* %foo) {
; CHECK-LABEL: @test15(
; CHECK-NEXT: call void @free(i8* [[FOO:%.*]]) #[[ATTR5:[0-9]+]]
; CHECK-NEXT: ret void
;
call void @free(i8* %foo) nofree
ret void
}
; TODO: freeing a nonnull nofree pointer -> full UB
define void @test16(i8* nonnull nofree %foo) {
; CHECK-LABEL: @test16(
; CHECK-NEXT: call void @free(i8* [[FOO:%.*]])
; CHECK-NEXT: ret void
;
call void @free(i8* %foo)
ret void
}
|
