llvm-mirror/test/Transforms/FunctionAttrs/2008-12-29-Constant.ll

; RUN: opt < %s -basicaa -functionattrs -S | grep readnone

@s = external constant i8		; <i8*> [#uses=1]

define i8 @f() {
	%tmp = load i8* @s		; <i8> [#uses=1]
	ret i8 %tmp
}
Extend the AliasAnalysis::pointsToConstantMemory interface to allow it to optionally look for constant or local (alloca) memory. Teach BasicAliasAnalysis::pointsToConstantMemory to look through Select and Phi nodes, and to support looking for local memory. Remove FunctionAttrs' PointsToLocalOrConstantMemory function, now that AliasAnalysis knows all the tricks that it knew. llvm-svn: 118412 2010-11-08 17:45:26 +01:00			`; RUN: opt < %s -basicaa -functionattrs -S \| grep readnone`
Allow readnone functions to read (and write!) global constants, since doing so is irrelevant for aliasing purposes. While this doesn't increase the total number of functions marked readonly or readnone in MultiSource/ Applications (3089), it does result in 12 functions being marked readnone rather than readonly. Before: readnone: 820 readonly: 2269 After: readnone: 832 readonly: 2257 llvm-svn: 61469 2008-12-29 12:34:09 +01:00
			`@s = external constant i8 ; <i8*> [#uses=1]`

			`define i8 @f() {`
			`%tmp = load i8* @s ; <i8> [#uses=1]`
			`ret i8 %tmp`
			`}`