[XCore] assertion rematerialising LDWSP instruction

[llvmbot]

Bugzilla Link	3324
Resolution	FIXED
Resolved on	Jan 14, 2009 12:34
Version	1.0
OS	Linux
Reporter	LLVM Bugzilla Contributor

Extended Description

In the target description LDWSP implicitly uses the SP register. This causes LiveIntervals to assert when rematerialising stack slot loads with the following code:

define double @​f1(double %a, double %b, double %c, double %d, double %e, double %f, double %g) nounwind {
entry:
br i1 false, label %bb113, label %bb129

bb113: ; preds = %entry
ret double 0.000000e+00

bb129: ; preds = %entry
%tmp134 = sub double %b, %a ; [#uses=1]
%tmp136 = sub double %tmp134, %c ; [#uses=1]
%tmp138 = add double %tmp136, %d ; [#uses=1]
%tmp140 = sub double %tmp138, %e ; [#uses=1]
%tmp142 = add double %tmp140, %f ; [#uses=1]
%tmp.0 = mul double %tmp142, 0.000000e+00 ; [#uses=1]
ret double %tmp.0
}

[llvmbot]

It looks like the solution is to have stack slot stores not marked with an implicit use of SP until frame indicies are eliminated. See:

http://lists.cs.uiuc.edu/pipermail/llvmdev/2009-January/019375.html

[llvmbot]

Fixed in r62238

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20090112/072150.html