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|
; RUN: opt < %s -instcombine -S | FileCheck %s
; PR1201
define i32 @main(i32 %argc, i8** %argv) {
; CHECK-LABEL: @main(
%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
; CHECK-NEXT: ret i32 0
}
declare noalias i8* @calloc(i32, i32) nounwind
declare noalias i8* @malloc(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
}
; CHECK-LABEL: @test5(
define void @test5(i8* %ptr, i8** %esc) {
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call i8* @malloc
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: call void @llvm.memmove
; CHECK-NEXT: store
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: call void @llvm.memmove
; CHECK-NEXT: call void @llvm.memset
; CHECK-NEXT: store volatile
; CHECK-NEXT: ret
%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.
; CHECK-LABEL: @test6(
define void @test6(i8* %foo) minsize {
; CHECK: %tobool = icmp eq i8* %foo, null
;; Call to free moved
; CHECK-NEXT: tail call void @free(i8* %foo)
; CHECK-NEXT: br i1 %tobool, label %if.end, label %if.then
; CHECK: if.then:
;; Block is now empty and may be simplified by simplifycfg
; 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* %foo)
br label %if.end
if.end: ; preds = %entry, %if.then
ret void
}
declare i8* @_ZnwmRKSt9nothrow_t(i64, i8*) nobuiltin
declare void @_ZdlPvRKSt9nothrow_t(i8*, i8*) nobuiltin
declare i32 @__gxx_personality_v0(...)
declare void @_ZN1AC2Ev(i8* %this)
; CHECK-LABEL: @test7(
define void @test7() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
entry:
%nt = alloca i8
; CHECK-NOT: call {{.*}}@_ZnwmRKSt9nothrow_t(
%call.i = tail call i8* @_ZnwmRKSt9nothrow_t(i64 1, i8* %nt) builtin nounwind
invoke void @_ZN1AC2Ev(i8* undef)
to label %.noexc.i unwind label %lpad.i
.noexc.i: ; preds = %entry
unreachable
lpad.i: ; preds = %entry
%0 = landingpad { i8*, i32 } cleanup
; CHECK-NOT: call {{.*}}@_ZdlPvRKSt9nothrow_t(
call void @_ZdlPvRKSt9nothrow_t(i8* %call.i, i8* %nt) builtin nounwind
resume { i8*, i32 } %0
}
declare i8* @_Znwm(i64) nobuiltin
define i8* @_Znwj(i32 %n) nobuiltin {
%z = zext i32 %n to i64
%m = call i8* @_Znwm(i64 %z)
ret i8* %m
}
declare i8* @_Znam(i64) nobuiltin
declare i8* @_Znaj(i32) nobuiltin
declare void @_ZdlPv(i8*) nobuiltin
declare void @_ZdaPv(i8*) nobuiltin
define linkonce void @_ZdlPvm(i8* %p, i64) nobuiltin {
call void @_ZdlPv(i8* %p)
ret void
}
define linkonce void @_ZdlPvj(i8* %p, i32) nobuiltin {
call void @_ZdlPv(i8* %p)
ret void
}
define linkonce void @_ZdaPvm(i8* %p, i64) nobuiltin {
call void @_ZdaPv(i8* %p)
ret void
}
define linkonce void @_ZdaPvj(i8* %p, i32) nobuiltin {
call void @_ZdaPv(i8* %p)
ret void
}
; new(size_t, align_val_t)
declare i8* @_ZnwmSt11align_val_t(i64, i64) nobuiltin
declare i8* @_ZnwjSt11align_val_t(i32, i32) nobuiltin
; new[](size_t, align_val_t)
declare i8* @_ZnamSt11align_val_t(i64, i64) nobuiltin
declare i8* @_ZnajSt11align_val_t(i32, i32) nobuiltin
; new(size_t, align_val_t, nothrow)
declare i8* @_ZnwmSt11align_val_tRKSt9nothrow_t(i64, i64, i8*) nobuiltin
declare i8* @_ZnwjSt11align_val_tRKSt9nothrow_t(i32, i32, i8*) nobuiltin
; new[](size_t, align_val_t, nothrow)
declare i8* @_ZnamSt11align_val_tRKSt9nothrow_t(i64, i64, i8*) nobuiltin
declare i8* @_ZnajSt11align_val_tRKSt9nothrow_t(i32, i32, i8*) nobuiltin
; delete(void*, align_val_t)
declare void @_ZdlPvSt11align_val_t(i8*, i64) nobuiltin
; delete[](void*, align_val_t)
declare void @_ZdaPvSt11align_val_t(i8*, i64) nobuiltin
; delete(void*, align_val_t, nothrow)
declare void @_ZdlPvSt11align_val_tRKSt9nothrow_t(i8*, i64, i8*) nobuiltin
; delete[](void*, align_val_t, nothrow)
declare void @_ZdaPvSt11align_val_tRKSt9nothrow_t(i8*, i64, i8*) nobuiltin
; CHECK-LABEL: @test8(
define void @test8() {
; CHECK-NOT: call
%nt = alloca i8
%nw = call i8* @_Znwm(i64 32) builtin
call void @_ZdlPv(i8* %nw) builtin
%na = call i8* @_Znam(i64 32) builtin
call void @_ZdaPv(i8* %na) builtin
%nwm = call i8* @_Znwm(i64 32) builtin
call void @_ZdlPvm(i8* %nwm, i64 32) builtin
%nwj = call i8* @_Znwj(i32 32) builtin
call void @_ZdlPvj(i8* %nwj, i32 32) builtin
%nam = call i8* @_Znam(i64 32) builtin
call void @_ZdaPvm(i8* %nam, i64 32) builtin
%naj = call i8* @_Znaj(i32 32) builtin
call void @_ZdaPvj(i8* %naj, i32 32) builtin
%nwa = call i8* @_ZnwmSt11align_val_t(i64 32, i64 8) builtin
call void @_ZdlPvSt11align_val_t(i8* %nwa, i64 8) builtin
%naa = call i8* @_ZnamSt11align_val_t(i64 32, i64 8) builtin
call void @_ZdaPvSt11align_val_t(i8* %naa, i64 8) builtin
%nwja = call i8* @_ZnwjSt11align_val_t(i32 32, i32 8) builtin
call void @_ZdlPvSt11align_val_t(i8* %nwja, i64 8) builtin
%naja = call i8* @_ZnajSt11align_val_t(i32 32, i32 8) builtin
call void @_ZdaPvSt11align_val_t(i8* %naja, i64 8) builtin
%nwat = call i8* @_ZnwmSt11align_val_tRKSt9nothrow_t(i64 32, i64 8, i8* %nt) builtin
call void @_ZdlPvSt11align_val_tRKSt9nothrow_t(i8* %nwat, i64 8, i8* %nt) builtin
%naat = call i8* @_ZnamSt11align_val_tRKSt9nothrow_t(i64 32, i64 8, i8* %nt) builtin
call void @_ZdaPvSt11align_val_tRKSt9nothrow_t(i8* %naat, i64 8, i8* %nt) builtin
%nwjat = call i8* @_ZnwjSt11align_val_tRKSt9nothrow_t(i32 32, i32 8, i8* %nt) builtin
call void @_ZdlPvSt11align_val_tRKSt9nothrow_t(i8* %nwjat, i64 8, i8* %nt) builtin
%najat = call i8* @_ZnajSt11align_val_tRKSt9nothrow_t(i32 32, i32 8, i8* %nt) builtin
call void @_ZdaPvSt11align_val_tRKSt9nothrow_t(i8* %najat, i64 8, i8* %nt) builtin
ret void
}
declare noalias i8* @"\01??2@YAPEAX_K@Z"(i64) nobuiltin
declare void @"\01??3@YAXPEAX@Z"(i8*) nobuiltin
; CHECK-LABEL: @test9(
define void @test9() {
; CHECK-NOT: call
%new_long_long = call noalias i8* @"\01??2@YAPEAX_K@Z"(i64 32) builtin
call void @"\01??3@YAXPEAX@Z"(i8* %new_long_long) builtin
ret void
}
define void @test10() {
; CHECK-LABEL: @test10
; CHECK: call void @_ZdlPv
call void @_ZdlPv(i8* null)
ret void
}
define void @test11() {
; CHECK-LABEL: @test11
; CHECK: call i8* @_Znwm
; CHECK: call void @_ZdlPv
%call = call i8* @_Znwm(i64 8) builtin
call void @_ZdlPv(i8* %call)
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.
; CHECK-LABEL: @test12(
define void @test12(i32* %foo) minsize {
; CHECK: %tobool = icmp eq i32* %foo, null
;; Everything before the call to free should have been moved as well.
; CHECK-NEXT: %bitcast = bitcast i32* %foo to i8*
;; Call to free moved
; CHECK-NEXT: tail call void @free(i8* %bitcast)
; CHECK-NEXT: br i1 %tobool, label %if.end, label %if.then
; CHECK: if.then:
;; Block is now empty and may be simplified by simplifycfg
; CHECK-NEXT: br label %if.end
; CHECK: if.end:
; CHECK-NEXT: ret void
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
}
|
