llvm/test/Transforms/ScalarRepl/phinodepromote.ll
Dan Gohman f2f6ce65b7 Change tests from "opt %s" to "opt < %s" so that opt doesn't see the
input filename so that opt doesn't print the input filename in the
output so that grep lines in the tests don't unintentionally match
strings in the input filename.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81537 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-11 18:01:28 +00:00

35 lines
1.3 KiB
LLVM

; RUN: opt < %s -simplifycfg -instcombine -mem2reg -S | not grep alloca
;
; This tests to see if mem2reg can promote alloca instructions whose addresses
; are used by PHI nodes that are immediately loaded. The LLVM C++ front-end
; often generates code that looks like this (when it codegen's ?: exprs as
; lvalues), so handling this simple extension is quite useful.
;
; This testcase is what the following program looks like when it reaches
; instcombine:
;
; template<typename T>
; const T& max(const T& a1, const T& a2) { return a1 < a2 ? a1 : a2; }
; int main() { return max(0, 1); }
;
; This test checks to make sure the combination of instcombine and mem2reg
; perform the transformation.
define i32 @main() {
entry:
%mem_tmp.0 = alloca i32 ; <i32*> [#uses=3]
%mem_tmp.1 = alloca i32 ; <i32*> [#uses=3]
store i32 0, i32* %mem_tmp.0
store i32 1, i32* %mem_tmp.1
%tmp.1.i = load i32* %mem_tmp.1 ; <i32> [#uses=1]
%tmp.3.i = load i32* %mem_tmp.0 ; <i32> [#uses=1]
%tmp.4.i = icmp sle i32 %tmp.1.i, %tmp.3.i ; <i1> [#uses=1]
br i1 %tmp.4.i, label %cond_true.i, label %cond_continue.i
cond_true.i: ; preds = %entry
br label %cond_continue.i
cond_continue.i: ; preds = %cond_true.i, %entry
%mem_tmp.i.0 = phi i32* [ %mem_tmp.1, %cond_true.i ], [ %mem_tmp.0, %entry ] ; <i32*> [#uses=1]
%tmp.3 = load i32* %mem_tmp.i.0 ; <i32> [#uses=1]
ret i32 %tmp.3
}