mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-10-30 16:17:05 +00:00
8573384010
When if converting something like: true: ... = R0<kill> false: ... = R0<kill> then the instructions of the true block must not have a <kill> flag anymore, as the instruction of the false block follow and do still read the R0 value. Specifically this patch determines the set of register live-in in the false block (possibly after simulating the liveness changes of the duplicated instructions). Each of these live-in registers mustn't be killed. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192482 91177308-0d34-0410-b5e6-96231b3b80d8
31 lines
877 B
LLVM
31 lines
877 B
LLVM
; RUN: llc < %s -march arm -mcpu swift -verify-machineinstrs
|
|
|
|
declare i32 @f(i32 %p0, i32 %p1)
|
|
|
|
define i32 @foo(i32* %ptr) {
|
|
entry:
|
|
%cmp = icmp ne i32* %ptr, null
|
|
br i1 %cmp, label %if.then, label %if.else
|
|
|
|
; present something which can be easily if-converted
|
|
if.then:
|
|
; %R0 should be killed here
|
|
%valt = load i32* %ptr, align 4
|
|
br label %return
|
|
|
|
if.else:
|
|
; %R0 should be killed here, however after if-conversion the %R0 kill
|
|
; has to be removed because if.then will follow after this and still
|
|
; read it.
|
|
%addr = getelementptr inbounds i32* %ptr, i32 4
|
|
%vale = load i32* %addr, align 4
|
|
br label %return
|
|
|
|
return:
|
|
%phival = phi i32 [ %valt, %if.then ], [ %vale, %if.else ]
|
|
; suggest to bring %phival/%valt/%vale into %R1 (because otherwise there
|
|
; will be no kills in if.then/if.else)
|
|
%retval = call i32 @f (i32 0, i32 %phival)
|
|
ret i32 %retval
|
|
}
|