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|
; RUN: opt < %s -basicaa -dse -S | FileCheck %s
target datalayout = "E-p:64:64:64-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128"
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
declare i8* @llvm.init.trampoline(i8*, i8*, i8*)
define void @test1(i32* %Q, i32* %P) {
%DEAD = load i32* %Q
store i32 %DEAD, i32* %P
store i32 0, i32* %P
ret void
; CHECK: @test1
; CHECK-NEXT: store i32 0, i32* %P
; CHECK-NEXT: ret void
}
; PR8576 - Should delete store of 10 even though p/q are may aliases.
define void @test2(i32 *%p, i32 *%q) {
store i32 10, i32* %p, align 4
store i32 20, i32* %q, align 4
store i32 30, i32* %p, align 4
ret void
; CHECK: @test2
; CHECK-NEXT: store i32 20
}
; PR8677
@g = global i32 1
define i32 @test3(i32* %g_addr) nounwind {
; CHECK: @test3
; CHECK: load i32* %g_addr
%g_value = load i32* %g_addr, align 4
store i32 -1, i32* @g, align 4
store i32 %g_value, i32* %g_addr, align 4
%tmp3 = load i32* @g, align 4
ret i32 %tmp3
}
define void @test4(i32* %Q) {
%a = load i32* %Q
store volatile i32 %a, i32* %Q
ret void
; CHECK: @test4
; CHECK-NEXT: load i32
; CHECK-NEXT: store volatile
; CHECK-NEXT: ret void
}
define void @test5(i32* %Q) {
%a = load volatile i32* %Q
store i32 %a, i32* %Q
ret void
; CHECK: @test5
; CHECK-NEXT: load volatile
; CHECK-NEXT: ret void
}
; Should delete store of 10 even though memset is a may-store to P (P and Q may
; alias).
define void @test6(i32 *%p, i8 *%q) {
store i32 10, i32* %p, align 4 ;; dead.
call void @llvm.memset.p0i8.i64(i8* %q, i8 42, i64 900, i32 1, i1 false)
store i32 30, i32* %p, align 4
ret void
; CHECK: @test6
; CHECK-NEXT: call void @llvm.memset
}
; Should delete store of 10 even though memcpy is a may-store to P (P and Q may
; alias).
define void @test7(i32 *%p, i8 *%q, i8* noalias %r) {
store i32 10, i32* %p, align 4 ;; dead.
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %q, i8* %r, i64 900, i32 1, i1 false)
store i32 30, i32* %p, align 4
ret void
; CHECK: @test7
; CHECK-NEXT: call void @llvm.memcpy
}
; Do not delete stores that are only partially killed.
define i32 @test8() {
%V = alloca i32
store i32 1234567, i32* %V
%V2 = bitcast i32* %V to i8*
store i8 0, i8* %V2
%X = load i32* %V
ret i32 %X
; CHECK: @test8
; CHECK: store i32 1234567
}
; Test for byval handling.
%struct.x = type { i32, i32, i32, i32 }
define void @test9(%struct.x* byval %a) nounwind {
%tmp2 = getelementptr %struct.x* %a, i32 0, i32 0
store i32 1, i32* %tmp2, align 4
ret void
; CHECK: @test9
; CHECK-NEXT: ret void
}
; va_arg has fuzzy dependence, the store shouldn't be zapped.
define double @test10(i8* %X) {
%X_addr = alloca i8*
store i8* %X, i8** %X_addr
%tmp.0 = va_arg i8** %X_addr, double
ret double %tmp.0
; CHECK: @test10
; CHECK: store
}
; DSE should delete the dead trampoline.
declare void @test11f()
define void @test11() {
; CHECK: @test11
%storage = alloca [10 x i8], align 16 ; <[10 x i8]*> [#uses=1]
; CHECK-NOT: alloca
%cast = getelementptr [10 x i8]* %storage, i32 0, i32 0 ; <i8*> [#uses=1]
%tramp = call i8* @llvm.init.trampoline( i8* %cast, i8* bitcast (void ()* @test11f to i8*), i8* null ) ; <i8*> [#uses=1]
; CHECK-NOT: trampoline
ret void
; CHECK: ret void
}
; PR2599 - load -> store to same address.
define void @test12({ i32, i32 }* %x) nounwind {
%tmp4 = getelementptr { i32, i32 }* %x, i32 0, i32 0
%tmp5 = load i32* %tmp4, align 4
%tmp7 = getelementptr { i32, i32 }* %x, i32 0, i32 1
%tmp8 = load i32* %tmp7, align 4
%tmp17 = sub i32 0, %tmp8
store i32 %tmp5, i32* %tmp4, align 4
store i32 %tmp17, i32* %tmp7, align 4
ret void
; CHECK: @test12
; CHECK-NOT: tmp5
; CHECK: ret void
}
; %P doesn't escape, the DEAD instructions should be removed.
declare void @test13f()
define i32* @test13() {
%p = tail call i8* @malloc(i32 4)
%P = bitcast i8* %p to i32*
%DEAD = load i32* %P
%DEAD2 = add i32 %DEAD, 1
store i32 %DEAD2, i32* %P
call void @test13f( )
store i32 0, i32* %P
ret i32* %P
; CHECK: @test13()
; CHECK-NEXT: malloc
; CHECK-NEXT: bitcast
; CHECK-NEXT: call void
}
declare noalias i8* @malloc(i32)
define void @test14(i32* %Q) {
%P = alloca i32
%DEAD = load i32* %Q
store i32 %DEAD, i32* %P
ret void
; CHECK: @test14
; CHECK-NEXT: ret void
}
; PR8701
;; Fully dead overwrite of memcpy.
define void @test15(i8* %P, i8* %Q) nounwind ssp {
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false)
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false)
ret void
; CHECK: @test15
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: ret
}
;; Full overwrite of smaller memcpy.
define void @test16(i8* %P, i8* %Q) nounwind ssp {
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 8, i32 1, i1 false)
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false)
ret void
; CHECK: @test16
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: ret
}
;; Overwrite of memset by memcpy.
define void @test17(i8* %P, i8* noalias %Q) nounwind ssp {
tail call void @llvm.memset.p0i8.i64(i8* %P, i8 42, i64 8, i32 1, i1 false)
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false)
ret void
; CHECK: @test17
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: ret
}
; Should not delete the volatile memset.
define void @test17v(i8* %P, i8* %Q) nounwind ssp {
tail call void @llvm.memset.p0i8.i64(i8* %P, i8 42, i64 8, i32 1, i1 true)
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false)
ret void
; CHECK: @test17v
; CHECK-NEXT: call void @llvm.memset
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: ret
}
; PR8728
; Do not delete instruction where possible situation is:
; A = B
; A = A
define void @test18(i8* %P, i8* %Q, i8* %R) nounwind ssp {
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i32 1, i1 false)
tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %R, i64 12, i32 1, i1 false)
ret void
; CHECK: @test18
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: call void @llvm.memcpy
; CHECK-NEXT: ret
}
; The store here is not dead because the byval call reads it.
declare void @test19f({i32}* byval align 4 %P)
define void @test19({i32} * nocapture byval align 4 %arg5) nounwind ssp {
bb:
%tmp7 = getelementptr inbounds {i32}* %arg5, i32 0, i32 0
store i32 912, i32* %tmp7
call void @test19f({i32}* byval align 4 %arg5)
ret void
; CHECK: @test19(
; CHECK: store i32 912
; CHECK: call void @test19f
}
|
