[XCore][Test] inline asm memory constraint not supported.

[nigelp-xmos]

Summary

XCore inline assembly only supports indirect memory constraints, for globals addressed relative to DP (data pointer) or CP (constant pointer) registers. It does not handle non-indirect memory constraints, or non-global memory operands.

[nigelp-xmos]

Tidy up.

[nigelp-xmos]

Invite inline assembly code owner to review.

[echristo]

You should error rather than xfail if you can.

Thanks!

-eric

[nigelp-xmos]

@echristo Thanks for the comment, Eric. I'm happy to do what is expected. Do you mean that it's a bug not to accept these cases, and we should fix it rather than XFAIL? So the build should not be green from XFAIL but only from a fix in this case?

[nigelp-xmos]

I'm looking at extending XCore inline asm, or at least understanding why it's a problem to handle these cases, to provide more context for any XFAIL.

[nigelp-xmos]

Currently the only memory operands that XCore inline asm supports are indirect (*m) and they have to be globals. It doesn’t handle locals as operands, or plain “m”. (It doesn’t handle FrameIndex.) So in that sense these tests are expected to fail. As an alternative to XFAIL, I’ve started looking at handling these other cases, or at least finding out what is difficult about them. I suspect there is some difficulty, otherwise the original developer would have done it, but I can’t say what it is yet.

llvm/test/CodeGen/Generic/2007-04-08-MultipleFrameIndices.ll

 ; RUN: llc -no-integrated-as < %s
-; XFAIL: sparc-sun-solaris2
+; XFAIL: sparc-sun-solaris2,xcore
 ; PR1308
 ; PR1557
 
 ; Bug: PR31336
 
 define i32 @stuff(i32, ...) {
         %foo = alloca i8*
         %bar = alloca i32*
         %A = call i32 asm sideeffect "inline asm $0 $2 $3 $4", "=r,0,i,m,m"( i32 0, i32 1, i8** %foo, i32** %bar )
         ret i32 %A
 }

llvm/test/CodeGen/Generic/2007-04-27-LargeMemObject.ll

 ; RUN: llc -no-integrated-as < %s
+; XFAIL: xcore
 
         %struct..0anon = type { [100 x i32] }
 
 define void @test() {
 entry:
         %currfpu = alloca %struct..0anon, align 16              ; <%struct..0anon*> [#uses=2]
         %mxcsr = alloca %struct..0anon, align 16                ; <%struct..0anon*> [#uses=1]
         call void asm sideeffect "fnstenv $0", "=*m,~{dirflag},~{fpsr},~{flags}"( %struct..0anon* %currfpu )
         call void asm sideeffect "$0  $1", "=*m,*m,~{dirflag},~{fpsr},~{flags}"( %struct..0anon* %mxcsr, %struct..0anon* %currfpu )
         ret void
 }
 

llvm/test/CodeGen/Generic/2007-12-17-InvokeAsm.ll

 ; RUN: llc -no-integrated-as < %s
+; XFAIL: xcore
 
 define fastcc void @bc__support__high_resolution_time__initialize_clock_rate() personality i32 (...)* @__gxx_personality_v0 {
 entry:
   invoke void asm "rdtsc\0A\09movl %eax, $0\0A\09movl %edx, $1", "=*imr,=*imr,~{dirflag},~{fpsr},~{flags},~{dx},~{ax}"( i32* null, i32* null )
       to label %.noexc unwind label %cleanup144
 
 .noexc:   ; preds = %entry
   ret void
 
 cleanup144:   ; preds = %entry
   %exn = landingpad {i8*, i32}
             cleanup
   resume { i8*, i32 } %exn
 }
 
 declare i32 @__gxx_personality_v0(...) addrspace(0)

llvm/test/CodeGen/Generic/2008-02-20-MatchingMem.ll

 ; RUN: llc -no-integrated-as < %s
 ; PR1133
+; XFAIL: xcore
 define void @test(i32* %X) nounwind  {
 entry:
   %tmp1 = getelementptr i32, i32* %X, i32 10    ; <i32*> [#uses=2]
   tail call void asm sideeffect " $0 $1 ", "=*im,*im,~{memory}"( i32* %tmp1, i32* %tmp1 ) nounwind 
   ret void
 }