mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-09-06 09:54:49 +00:00
GEPs, bit casts, and stores reaching it but no other instructions. These often show up during the iterative processing of the inliner, SROA, and DCE. Once we hit this point, we can completely remove the alloca. These were actually showing up in the final, fully optimized code in a bunch of inliner tests I've been working on, and notably they show up after LLVM finishes optimizing away all function calls involved in hash_combine(a, b). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154285 91177308-0d34-0410-b5e6-96231b3b80d8
91 lines
2.3 KiB
LLVM
91 lines
2.3 KiB
LLVM
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"
|
|
|
|
; RUN: opt < %s -instcombine -S | FileCheck %s
|
|
; END.
|
|
|
|
declare void @use(...)
|
|
|
|
; Zero byte allocas should be deleted.
|
|
; CHECK: @test
|
|
; CHECK-NOT: alloca
|
|
define void @test() {
|
|
%X = alloca [0 x i32] ; <[0 x i32]*> [#uses=1]
|
|
call void (...)* @use( [0 x i32]* %X )
|
|
%Y = alloca i32, i32 0 ; <i32*> [#uses=1]
|
|
call void (...)* @use( i32* %Y )
|
|
%Z = alloca { } ; <{ }*> [#uses=1]
|
|
call void (...)* @use( { }* %Z )
|
|
ret void
|
|
}
|
|
|
|
; Zero byte allocas should be deleted.
|
|
; CHECK: @test2
|
|
; CHECK-NOT: alloca
|
|
define void @test2() {
|
|
%A = alloca i32 ; <i32*> [#uses=1]
|
|
store i32 123, i32* %A
|
|
ret void
|
|
}
|
|
|
|
; Zero byte allocas should be deleted.
|
|
; CHECK: @test3
|
|
; CHECK-NOT: alloca
|
|
define void @test3() {
|
|
%A = alloca { i32 } ; <{ i32 }*> [#uses=1]
|
|
%B = getelementptr { i32 }* %A, i32 0, i32 0 ; <i32*> [#uses=1]
|
|
store i32 123, i32* %B
|
|
ret void
|
|
}
|
|
|
|
; CHECK: @test4
|
|
; CHECK: = zext i32 %n to i64
|
|
; CHECK: %A = alloca i32, i64 %
|
|
define i32* @test4(i32 %n) {
|
|
%A = alloca i32, i32 %n
|
|
ret i32* %A
|
|
}
|
|
|
|
; Allocas which are only used by GEPs, bitcasts, and stores (transitively)
|
|
; should be deleted.
|
|
define void @test5() {
|
|
; CHECK: @test5
|
|
; CHECK-NOT: alloca
|
|
; CHECK-NOT: store
|
|
; CHECK: ret
|
|
|
|
entry:
|
|
%a = alloca { i32 }
|
|
%b = alloca i32*
|
|
%a.1 = getelementptr { i32 }* %a, i32 0, i32 0
|
|
store i32 123, i32* %a.1
|
|
store i32* %a.1, i32** %b
|
|
%b.1 = bitcast i32** %b to i32*
|
|
store i32 123, i32* %b.1
|
|
%a.2 = getelementptr { i32 }* %a, i32 0, i32 0
|
|
store atomic i32 2, i32* %a.2 unordered, align 4
|
|
%a.3 = getelementptr { i32 }* %a, i32 0, i32 0
|
|
store atomic i32 3, i32* %a.3 release, align 4
|
|
%a.4 = getelementptr { i32 }* %a, i32 0, i32 0
|
|
store atomic i32 4, i32* %a.4 seq_cst, align 4
|
|
ret void
|
|
}
|
|
|
|
declare void @f(i32* %p)
|
|
|
|
; Check that we don't delete allocas in some erroneous cases.
|
|
define void @test6() {
|
|
; CHECK: @test6
|
|
; CHECK-NOT: ret
|
|
; CHECK: alloca
|
|
; CHECK-NEXT: alloca
|
|
; CHECK: ret
|
|
|
|
entry:
|
|
%a = alloca { i32 }
|
|
%b = alloca i32
|
|
%a.1 = getelementptr { i32 }* %a, i32 0, i32 0
|
|
store volatile i32 123, i32* %a.1
|
|
tail call void @f(i32* %b)
|
|
ret void
|
|
}
|