llvm/test/Transforms/InstCombine/allocsize.ll
George Burgess IV 274105b8b5 Add the allocsize attribute to LLVM.
`allocsize` is a function attribute that allows users to request that
LLVM treat arbitrary functions as allocation functions.

This patch makes LLVM accept the `allocsize` attribute, and makes
`@llvm.objectsize` recognize said attribute.

The review for this was split into two patches for ease of reviewing:
D18974 and D14933. As promised on the revisions, I'm landing both
patches as a single commit.

Differential Revision: http://reviews.llvm.org/D14933


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266032 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-12 01:05:35 +00:00

142 lines
4.6 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
;
; Test that instcombine folds allocsize function calls properly.
; Dummy arguments are inserted to verify that allocsize is picking the right
; args, and to prove that arbitrary unfoldable values don't interfere with
; allocsize if they're not used by allocsize.
declare i8* @my_malloc(i8*, i32) allocsize(1)
declare i8* @my_calloc(i8*, i8*, i32, i32) allocsize(2, 3)
; CHECK-LABEL: define void @test_malloc
define void @test_malloc(i8** %p, i64* %r) {
%1 = call i8* @my_malloc(i8* null, i32 100)
store i8* %1, i8** %p, align 8 ; To ensure objectsize isn't killed
%2 = call i64 @llvm.objectsize.i64.p0i8(i8* %1, i1 false)
; CHECK: store i64 100
store i64 %2, i64* %r, align 8
ret void
}
; CHECK-LABEL: define void @test_calloc
define void @test_calloc(i8** %p, i64* %r) {
%1 = call i8* @my_calloc(i8* null, i8* null, i32 100, i32 5)
store i8* %1, i8** %p, align 8 ; To ensure objectsize isn't killed
%2 = call i64 @llvm.objectsize.i64.p0i8(i8* %1, i1 false)
; CHECK: store i64 500
store i64 %2, i64* %r, align 8
ret void
}
; Failure cases with non-constant values...
; CHECK-LABEL: define void @test_malloc_fails
define void @test_malloc_fails(i8** %p, i64* %r, i32 %n) {
%1 = call i8* @my_malloc(i8* null, i32 %n)
store i8* %1, i8** %p, align 8 ; To ensure objectsize isn't killed
; CHECK: @llvm.objectsize.i64.p0i8
%2 = call i64 @llvm.objectsize.i64.p0i8(i8* %1, i1 false)
store i64 %2, i64* %r, align 8
ret void
}
; CHECK-LABEL: define void @test_calloc_fails
define void @test_calloc_fails(i8** %p, i64* %r, i32 %n) {
%1 = call i8* @my_calloc(i8* null, i8* null, i32 %n, i32 5)
store i8* %1, i8** %p, align 8 ; To ensure objectsize isn't killed
; CHECK: @llvm.objectsize.i64.p0i8
%2 = call i64 @llvm.objectsize.i64.p0i8(i8* %1, i1 false)
store i64 %2, i64* %r, align 8
%3 = call i8* @my_calloc(i8* null, i8* null, i32 100, i32 %n)
store i8* %3, i8** %p, align 8 ; To ensure objectsize isn't killed
; CHECK: @llvm.objectsize.i64.p0i8
%4 = call i64 @llvm.objectsize.i64.p0i8(i8* %3, i1 false)
store i64 %4, i64* %r, align 8
ret void
}
declare i8* @my_malloc_outofline(i8*, i32) #0
declare i8* @my_calloc_outofline(i8*, i8*, i32, i32) #1
; Verifying that out of line allocsize is parsed correctly
; CHECK-LABEL: define void @test_outofline
define void @test_outofline(i8** %p, i64* %r) {
%1 = call i8* @my_malloc_outofline(i8* null, i32 100)
store i8* %1, i8** %p, align 8 ; To ensure objectsize isn't killed
%2 = call i64 @llvm.objectsize.i64.p0i8(i8* %1, i1 false)
; CHECK: store i64 100
store i64 %2, i64* %r, align 8
%3 = call i8* @my_calloc_outofline(i8* null, i8* null, i32 100, i32 5)
store i8* %3, i8** %p, align 8 ; To ensure objectsize isn't killed
%4 = call i64 @llvm.objectsize.i64.p0i8(i8* %3, i1 false)
; CHECK: store i64 500
store i64 %4, i64* %r, align 8
ret void
}
declare i8* @my_malloc_i64(i8*, i64) #0
declare i8* @my_tiny_calloc(i8*, i8*, i8, i8) #1
declare i8* @my_varied_calloc(i8*, i8*, i32, i8) #1
; CHECK-LABEL: define void @test_overflow
define void @test_overflow(i8** %p, i32* %r) {
%r64 = bitcast i32* %r to i64*
; (2**31 + 1) * 2 > 2**31. So overflow. Yay.
%big_malloc = call i8* @my_calloc(i8* null, i8* null, i32 2147483649, i32 2)
store i8* %big_malloc, i8** %p, align 8
; CHECK: @llvm.objectsize
%1 = call i32 @llvm.objectsize.i32.p0i8(i8* %big_malloc, i1 false)
store i32 %1, i32* %r, align 4
%big_little_malloc = call i8* @my_tiny_calloc(i8* null, i8* null, i8 127, i8 4)
store i8* %big_little_malloc, i8** %p, align 8
; CHECK: store i32 508
%2 = call i32 @llvm.objectsize.i32.p0i8(i8* %big_little_malloc, i1 false)
store i32 %2, i32* %r, align 4
; malloc(2**33)
%big_malloc_i64 = call i8* @my_malloc_i64(i8* null, i64 8589934592)
store i8* %big_malloc_i64, i8** %p, align 8
; CHECK: @llvm.objectsize
%3 = call i32 @llvm.objectsize.i32.p0i8(i8* %big_malloc_i64, i1 false)
store i32 %3, i32* %r, align 4
%4 = call i64 @llvm.objectsize.i64.p0i8(i8* %big_malloc_i64, i1 false)
; CHECK: store i64 8589934592
store i64 %4, i64* %r64, align 8
; Just intended to ensure that we properly handle args of different types...
%varied_calloc = call i8* @my_varied_calloc(i8* null, i8* null, i32 1000, i8 5)
store i8* %varied_calloc, i8** %p, align 8
; CHECK: store i32 5000
%5 = call i32 @llvm.objectsize.i32.p0i8(i8* %varied_calloc, i1 false)
store i32 %5, i32* %r, align 4
ret void
}
attributes #0 = { allocsize(1) }
attributes #1 = { allocsize(2, 3) }
declare i32 @llvm.objectsize.i32.p0i8(i8*, i1)
declare i64 @llvm.objectsize.i64.p0i8(i8*, i1)