564d85e090
In LLVM IR, `AlignmentBitfieldElementT` is 5-bit wide But that means that the maximal alignment exponent is `(1<<5)-2`, which is `30`, not `29`. And indeed, alignment of `1073741824` roundtrips IR serialization-deserialization. While this doesn't seem all that important, this doubles the maximal supported alignment from 512MiB to 1GiB, and there's actually one noticeable use-case for that; On X86, the huge pages can have sizes of 2MiB and 1GiB (!). So while this doesn't add support for truly huge alignments, which i think we can easily-ish do if wanted, i think this adds zero-cost support for a not-trivially-dismissable case. I don't believe we need any upgrade infrastructure, and since we don't explicitly record the IR version, we don't need to bump one either. As @craig.topper speculates in D108661#2963519, this might be an artificial limit imposed by the original implementation of the `getAlignment()` functions. Differential Revision: https://reviews.llvm.org/D108661
60 lines
1.2 KiB
LLVM
60 lines
1.2 KiB
LLVM
; RUN: not llvm-as < %s -o /dev/null 2>&1 | FileCheck %s
|
|
|
|
declare i8* @foo()
|
|
|
|
define void @f1() {
|
|
entry:
|
|
call i8* @foo(), !align !{i64 2}
|
|
ret void
|
|
}
|
|
; CHECK: align applies only to load instructions
|
|
; CHECK-NEXT: call i8* @foo()
|
|
|
|
define i8 @f2(i8* %x) {
|
|
entry:
|
|
%y = load i8, i8* %x, !align !{i64 2}
|
|
ret i8 %y
|
|
}
|
|
; CHECK: align applies only to pointer types
|
|
; CHECK-NEXT: load i8, i8* %x
|
|
|
|
define i8* @f3(i8** %x) {
|
|
entry:
|
|
%y = load i8*, i8** %x, !align !{}
|
|
ret i8* %y
|
|
}
|
|
; CHECK: align takes one operand
|
|
; CHECK-NEXT: load i8*, i8** %x
|
|
|
|
define i8* @f4(i8** %x) {
|
|
entry:
|
|
%y = load i8*, i8** %x, !align !{!"str"}
|
|
ret i8* %y
|
|
}
|
|
; CHECK: align metadata value must be an i64!
|
|
; CHECK-NEXT: load i8*, i8** %x
|
|
|
|
define i8* @f5(i8** %x) {
|
|
entry:
|
|
%y = load i8*, i8** %x, !align !{i32 2}
|
|
ret i8* %y
|
|
}
|
|
; CHECK: align metadata value must be an i64!
|
|
; CHECK-NEXT: load i8*, i8** %x
|
|
|
|
define i8* @f6(i8** %x) {
|
|
entry:
|
|
%y = load i8*, i8** %x, !align !{i64 3}
|
|
ret i8* %y
|
|
}
|
|
; CHECK: align metadata value must be a power of 2!
|
|
; CHECK-NEXT: load i8*, i8** %x
|
|
|
|
define i8* @f7(i8** %x) {
|
|
entry:
|
|
%y = load i8*, i8** %x, !align !{i64 2147483648}
|
|
ret i8* %y
|
|
}
|
|
; CHECK: alignment is larger that implementation defined limit
|
|
; CHECK-NEXT: load i8*, i8** %x
|