llvm-6502/test/Transforms/LoopUnswitch/basictest.ll
James Molloy 67ae135759 Add a new attribute, 'noduplicate'. If a function contains a noduplicate call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call.
Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170704 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 16:04:27 +00:00

69 lines
1.9 KiB
LLVM

; RUN: opt < %s -loop-unswitch -verify-loop-info -S < %s 2>&1 | FileCheck %s
define i32 @test(i32* %A, i1 %C) {
entry:
br label %no_exit
no_exit: ; preds = %no_exit.backedge, %entry
%i.0.0 = phi i32 [ 0, %entry ], [ %i.0.0.be, %no_exit.backedge ] ; <i32> [#uses=3]
%gep.upgrd.1 = zext i32 %i.0.0 to i64 ; <i64> [#uses=1]
%tmp.7 = getelementptr i32* %A, i64 %gep.upgrd.1 ; <i32*> [#uses=4]
%tmp.13 = load i32* %tmp.7 ; <i32> [#uses=2]
%tmp.14 = add i32 %tmp.13, 1 ; <i32> [#uses=1]
store i32 %tmp.14, i32* %tmp.7
br i1 %C, label %then, label %endif
then: ; preds = %no_exit
%tmp.29 = load i32* %tmp.7 ; <i32> [#uses=1]
%tmp.30 = add i32 %tmp.29, 2 ; <i32> [#uses=1]
store i32 %tmp.30, i32* %tmp.7
%inc9 = add i32 %i.0.0, 1 ; <i32> [#uses=2]
%tmp.112 = icmp ult i32 %inc9, 100000 ; <i1> [#uses=1]
br i1 %tmp.112, label %no_exit.backedge, label %return
no_exit.backedge: ; preds = %endif, %then
%i.0.0.be = phi i32 [ %inc9, %then ], [ %inc, %endif ] ; <i32> [#uses=1]
br label %no_exit
endif: ; preds = %no_exit
%inc = add i32 %i.0.0, 1 ; <i32> [#uses=2]
%tmp.1 = icmp ult i32 %inc, 100000 ; <i1> [#uses=1]
br i1 %tmp.1, label %no_exit.backedge, label %return
return: ; preds = %endif, %then
ret i32 %tmp.13
}
; This simple test would normally unswitch, but should be inhibited by the presence of
; the noduplicate call.
; CHECK: @test2
define i32 @test2(i32* %var) {
%mem = alloca i32
store i32 2, i32* %mem
%c = load i32* %mem
br label %loop_begin
loop_begin:
%var_val = load i32* %var
switch i32 %c, label %default [
i32 1, label %inc
i32 2, label %dec
]
inc:
call void @incf() noreturn nounwind
br label %loop_begin
dec:
; CHECK: call void @decf()
; CHECK-NOT: call void @decf()
call void @decf() noreturn nounwind noduplicate
br label %loop_begin
default:
br label %loop_exit
loop_exit:
ret i32 0
; CHECK: }
}
declare void @incf() noreturn
declare void @decf() noreturn