Florian Hahn 9d172c8e9c Recommit "[DSE] Switch to MemorySSA-backed DSE by default."
This switches to using DSE + MemorySSA by default again, after
fixing the issues reported after the first commit.

Notable fixes fc8200633122, a0017c2bc258.

This reverts commit 3a59628f3cc26eb085acfc9cbdc97243ef71a6c5.
2020-09-18 11:05:00 +01:00

41 lines
876 B
LLVM

; RUN: opt -basic-aa -dse -S < %s | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
%t = type { i32 }
@g = global i32 42
define void @test1(%t* noalias %pp) {
%p = getelementptr inbounds %t, %t* %pp, i32 0, i32 0
store i32 1, i32* %p; <-- This is dead
%x = load i32, i32* inttoptr (i32 12345 to i32*)
store i32 %x, i32* %p
ret void
; CHECK-LABEL: define void @test1(
; CHECK: store
; CHECK-NOT: store
; CHECK: ret void
}
define void @test3() {
store i32 1, i32* @g; <-- This is dead.
store i32 42, i32* @g
ret void
; CHECK-LABEL: define void @test3(
; CHECK: store
; CHECK-NOT: store
; CHECK: ret void
}
define void @test4(i32* %p) {
store i32 1, i32* %p
%x = load i32, i32* @g; <-- %p and @g could alias
store i32 %x, i32* %p
ret void
; CHECK-LABEL: define void @test4(
; CHECK: store
; CHECK: store
; CHECK: ret void
}