llvm-project/llvm/test/Analysis/LoadVN/call_pure_function.ll
Duncan Sands 8a3e9d2bee Ding dong, the DoesntAccessMemoryFns and
OnlyReadsMemoryFns tables are dead!  We
get more, and more accurate, information
from gcc via the readnone and readonly
function attributes.

llvm-svn: 44288
2007-11-23 19:30:27 +00:00

15 lines
393 B
LLVM

; RUN: llvm-as < %s | opt -basicaa -load-vn -gcse -instcombine | llvm-dis | not grep sub
declare i32 @strlen(i8*) readonly
declare void @use(i32)
define i8 @test(i8* %P, i8* %Q) {
%A = load i8* %Q ; <i8> [#uses=1]
%X = call i32 @strlen( i8* %P ) readonly ; <i32> [#uses=1]
%B = load i8* %Q ; <i8> [#uses=1]
call void @use( i32 %X )
%C = sub i8 %A, %B ; <i8> [#uses=1]
ret i8 %C
}