xref: /llvm-project/llvm/test/Transforms/Reassociate/vaarg_movable.ll (revision ab7dba233a058cc8310ef829929238b5d8440b30)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -S -passes=reassociate,dce < %s | FileCheck %s
3
4; The two va_arg instructions depend on the memory/context, are therfore not
5; identical and the sub should not be optimized to 0 by reassociate.
6;
7; ...
8; ...
9define i32 @func(i32 %dummy, ...) {
10;
11; CHECK-LABEL: @func(
12; CHECK-NEXT:    [[VARARGS:%.*]] = alloca ptr, align 8
13; CHECK-NEXT:    call void @llvm.va_start.p0(ptr [[VARARGS]])
14; CHECK-NEXT:    [[V0:%.*]] = va_arg ptr [[VARARGS]], i32
15; CHECK-NEXT:    [[V1:%.*]] = va_arg ptr [[VARARGS]], i32
16; CHECK-NEXT:    [[V0_NEG:%.*]] = sub i32 0, [[V0]]
17; CHECK-NEXT:    [[SUB:%.*]] = add i32 [[V0_NEG]], 1
18; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[SUB]], [[V1]]
19; CHECK-NEXT:    call void @llvm.va_end.p0(ptr [[VARARGS]])
20; CHECK-NEXT:    ret i32 [[ADD]]
21;
22  %varargs = alloca ptr, align 8
23  call void @llvm.va_start(ptr %varargs)
24  %v0 = va_arg ptr %varargs, i32
25  %v1 = va_arg ptr %varargs, i32
26  %sub = sub nsw i32 %v1, %v0
27  %add = add nsw i32 %sub, 1
28  call void @llvm.va_end(ptr %varargs)
29  ret i32 %add
30}
31
32declare void @llvm.va_start(ptr)
33declare void @llvm.va_end(ptr)
34