1 ; RUN: opt < %s -simplifycfg -S | FileCheck %s 2 ; 3 ; rdar:13349374 4 ; 5 ; SimplifyCFG should not eliminate blocks with volatile stores. 6 ; Essentially, volatile needs to be backdoor that tells the optimizer 7 ; it can no longer use language standard as an excuse. The compiler 8 ; needs to expose the volatile access to the platform. 9 ; 10 ; CHECK-LABEL: @test( 11 ; CHECK: entry: 12 ; CHECK: @Trace 13 ; CHECK: while.body: 14 ; CHECK: store volatile 15 ; CHECK: end: 16 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" 17 18 define void @test(i8** nocapture %PeiServices) #0 { 19 entry: 20 %call = tail call i32 (...)* @Trace() #2 21 %tobool = icmp eq i32 %call, 0 22 br i1 %tobool, label %while.body, label %if.then 23 24 if.then: ; preds = %entry 25 %call1 = tail call i32 (...)* @Trace() #2 26 br label %while.body 27 28 while.body: ; preds = %entry, %if.then, %while.body 29 %Addr.017 = phi i8* [ %incdec.ptr, %while.body ], [ null, %if.then ], [ null, %entry ] 30 %x.016 = phi i8 [ %inc, %while.body ], [ 0, %if.then ], [ 0, %entry ] 31 %inc = add i8 %x.016, 1 32 %incdec.ptr = getelementptr inbounds i8* %Addr.017, i64 1 33 store volatile i8 %x.016, i8* %Addr.017, align 1 34 %0 = ptrtoint i8* %incdec.ptr to i64 35 %1 = trunc i64 %0 to i32 36 %cmp = icmp ult i32 %1, 4096 37 br i1 %cmp, label %while.body, label %end 38 39 end: 40 ret void 41 } 42 declare i32 @Trace(...) #1 43 44 attributes #0 = { nounwind ssp uwtable "fp-contract-model"="standard" "no-frame-pointer-elim" "no-frame-pointer-elim-non-leaf" "relocation-model"="pic" "ssp-buffers-size"="8" } 45 attributes #1 = { "fp-contract-model"="standard" "no-frame-pointer-elim" "no-frame-pointer-elim-non-leaf" "relocation-model"="pic" "ssp-buffers-size"="8" } 46 attributes #2 = { nounwind } 47 48 !0 = metadata !{i32 1039} 49
