Incomplete breakdown of soft-float vectors

[stoklund]

Bugzilla Link	3898
Resolution	FIXED
Resolved on	Apr 18, 2009 15:49
Version	trunk
OS	All
Attachments	Test case for XCore backend, Fix for TargetLowering::getVectorTypeBreakdown
CC	@asl

Extended Description

On a target with soft-float and only i32 registers, a <2 x double> vector is legalized as follows:

v2f64 -> 2 x i64 -> 4 x i32

TargetLowering::getVectorTypeBreakdown() misses the last step, and a FORMAL_ARGUMENTS node with two illegal i64 parameters is created. This triggers an assert in XCoreTargetLowering::LowerCCCArguments()

I believe this bug only affects the XCore backend, but it is not a bug /in/ the XCore backend. I found it while writing a new Blackfin backend.

[stoklund]

This bug is also trigged by:

llc -march=x86 -soft-float
llc -march=arm -soft-float
llc -march=thumb -soft-float

[lattner]

Patch applied here, thanks!
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20090413/076455.html
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20090413/076456.html