The old system was fairly convoluted:
* A temporary label was created.
* A single PROLOG_LABEL was created with it.
* A few MCCFIInstructions were created with the same label.
The semantics were that the cfi instructions were mapped to the PROLOG_LABEL
via the temporary label. The output position was that of the PROLOG_LABEL.
The temporary label itself was used only for doing the mapping.
The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to
one by holding an index into the CFI instructions of this function.
I did consider removing MMI.getFrameInstructions completelly and having
CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non
trivial constructors and destructors and are somewhat big, so the this setup
is probably better.
The net result is that we don't create temporary labels that are never used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203204 91177308-0d34-0410-b5e6-96231b3b80d8
If a function returns a large struct by value return the first 4 words
in registers and the rest on the stack in a location reserved by the
caller. This is needed to support the xC language which supports
functions returning an arbitrary number of return values. This is
r202397 reapplied with a fix to avoid an uninitialized read of a member.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202414 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
If a function returns a large struct by value return the first 4 words
in registers and the rest on the stack in a location reserved by the
caller. This is needed to support the xC language which supports
functions returning an arbitrary number of return values.
Reviewers: robertlytton
Reviewed By: robertlytton
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2889
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202397 91177308-0d34-0410-b5e6-96231b3b80d8
We also narrow the liveness of FP & LR during the prologue to
reflect the actual usage of the registers.
I have been unable to construct a test to prove the previous live
range was too large.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198611 91177308-0d34-0410-b5e6-96231b3b80d8
eliminateFrameIndex() has been reworked to handle both small & large frames
with either a FP or SP.
An additional Slot is required for Scavenging spills when not using FP for large frames.
Reworked the handling of Register Scavenging.
Whether we are using an FP or not, whether it is a large frame or not,
and whether we are using a large code model or not are now independent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196091 91177308-0d34-0410-b5e6-96231b3b80d8
missed in the first pass because the script didn't yet handle include
guards.
Note that the script is now able to handle all of these headers without
manual edits. =]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169224 91177308-0d34-0410-b5e6-96231b3b80d8
