maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/llvm/test/Assembler/alloca-size-one.ll

12 lines
305 B
LLVM
Raw Normal View History

AsmWriter: Write alloca array size explicitly (and -instcombine fixup) Write the `alloca` array size explicitly when it's non-canonical. Previously, if the array size was `iX 1` (where X is not 32), the type would mutate to `i32` when round-tripping through assembly. The testcase I added fails in `verify-uselistorder` (as well as `FileCheck`), since the use-lists for `i32 1` and `i64 1` change. (Manman Ren came across this when running `verify-uselistorder` on some non-trivial, optimized code as part of PR5680.) The type mutation started with r104911, which allowed array sizes to be something other than an `i32`. Starting with r204945, we "canonicalized" to `i64` on 64-bit platforms -- and then on every round-trip through assembly, mutated back to `i32`. I bundled a fixup for `-instcombine` to avoid r204945 on scalar allocations. (There wasn't a clean way to sequence this into two commits, since the assembly change on its own caused testcase churn, and the `-instcombine` change can't be tested without the assembly changes.) An obvious alternative fix -- change `AllocaInst::AllocaInst()`, `AsmWriter` and `LLParser` to treat `intptr_t` as the canonical type for scalar allocations -- was rejected out of hand, since this required teaching them each about the data layout. A follow-up commit will add an `-instcombine` to canonicalize the scalar allocation array size to `i32 1` rather than leaving `iX 1` alone. rdar://problem/20075773 llvm-svn: 232200
2015-03-14 03:30:44 +08:00
; RUN: llvm-as < %s | llvm-dis | llvm-as | llvm-dis | FileCheck %s
; RUN: verify-uselistorder %s
define void @foo() {
entry:
; CHECK: %alloc32 = alloca i1, align 8
; CHECK: %alloc64 = alloca i1, i64 1, align 8
%alloc32 = alloca i1, i32 1, align 8
%alloc64 = alloca i1, i64 1, align 8
unreachable
}