llvm-6502/test/Transforms/FunctionAttrs/2008-10-04-LocalMemory.ll

; RUN: llvm-as < %s | opt -functionattrs | llvm-dis | grep readnone | count 2

declare i32 @g(i32*) readnone

define i32 @f() {
	%x = alloca i32		; <i32*> [#uses=2]
	store i32 0, i32* %x
	%y = call i32 @g(i32* %x)		; <i32> [#uses=1]
	ret i32 %y
}
Rename AddReadAttrs to FunctionAttrs, and teach it how to work out (in a very simplistic way) which function arguments (pointer arguments only) are only dereferenced and so do not escape. Mark such arguments 'nocapture'. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61525 91177308-0d34-0410-b5e6-96231b3b80d8 2008-12-31 16:14:43 +00:00			`; RUN: llvm-as < %s \| opt -functionattrs \| llvm-dis \| grep readnone \| count 2`
Ignore loads from and stores to local memory (i.e. allocas) when deciding whether to mark a function readnone/readonly. Since the pass is currently run before SROA, this may be quite helpful. Requested by Chris on IRC. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57050 91177308-0d34-0410-b5e6-96231b3b80d8 2008-10-04 13:24:24 +00:00
			`declare i32 @g(i32*) readnone`

			`define i32 @f() {`
			`%x = alloca i32 ; <i32*> [#uses=2]`
			`store i32 0, i32* %x`
			`%y = call i32 @g(i32* %x) ; <i32> [#uses=1]`
			`ret i32 %y`
			`}`