49 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			49 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: opt < %s -simplifycfg -S | FileCheck %s
 | |
| ;
 | |
| ; rdar:13349374
 | |
| ;
 | |
| ; SimplifyCFG should not eliminate blocks with volatile stores.
 | |
| ; Essentially, volatile needs to be backdoor that tells the optimizer
 | |
| ; it can no longer use language standard as an excuse. The compiler
 | |
| ; needs to expose the volatile access to the platform.
 | |
| ;
 | |
| ; CHECK: @test
 | |
| ; CHECK: entry:
 | |
| ; CHECK: @Trace
 | |
| ; CHECK: while.body:
 | |
| ; CHECK: store volatile
 | |
| ; CHECK: end:
 | |
| 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"
 | |
| 
 | |
| define void @test(i8** nocapture %PeiServices) #0 {
 | |
| entry:
 | |
|   %call = tail call i32 (...)* @Trace() #2
 | |
|   %tobool = icmp eq i32 %call, 0
 | |
|   br i1 %tobool, label %while.body, label %if.then
 | |
| 
 | |
| if.then:                                          ; preds = %entry
 | |
|   %call1 = tail call i32 (...)* @Trace() #2
 | |
|   br label %while.body
 | |
| 
 | |
| while.body:                                       ; preds = %entry, %if.then, %while.body
 | |
|   %Addr.017 = phi i8* [ %incdec.ptr, %while.body ], [ null, %if.then ], [ null, %entry ]
 | |
|   %x.016 = phi i8 [ %inc, %while.body ], [ 0, %if.then ], [ 0, %entry ]
 | |
|   %inc = add i8 %x.016, 1
 | |
|   %incdec.ptr = getelementptr inbounds i8* %Addr.017, i64 1
 | |
|   store volatile i8 %x.016, i8* %Addr.017, align 1
 | |
|   %0 = ptrtoint i8* %incdec.ptr to i64
 | |
|   %1 = trunc i64 %0 to i32
 | |
|   %cmp = icmp ult i32 %1, 4096
 | |
|   br i1 %cmp, label %while.body, label %end
 | |
| 
 | |
| end:
 | |
|   ret void
 | |
| }
 | |
| declare i32 @Trace(...) #1
 | |
| 
 | |
| attributes #0 = { nounwind ssp uwtable "fp-contract-model"="standard" "no-frame-pointer-elim" "no-frame-pointer-elim-non-leaf" "realign-stack" "relocation-model"="pic" "ssp-buffers-size"="8" }
 | |
| attributes #1 = { "fp-contract-model"="standard" "no-frame-pointer-elim" "no-frame-pointer-elim-non-leaf" "realign-stack" "relocation-model"="pic" "ssp-buffers-size"="8" }
 | |
| attributes #2 = { nounwind }
 | |
| 
 | |
| !0 = metadata !{i32 1039}
 |