== Progress ==

- Travelling from TCWG sprint (2/10)

- Zero/sign extension elimination (TCWG-291) 2/10
  * Posted the modified patch and some discussions. Further testing.

-SHA1 regression (TCWG-468) 4/10
  * Looked at IRA's uses of back end cost model. It might be a
limitation (See the notes below). Looking at the test-case from sha1
which also has inline asm whose constraints are causing  further issues.

- Misc (2/10)
  * Looked at bugs assigned (https://bugs.linaro.org/show_bug.cgi?id=85)
  * Set-up LLVM

== Plan ==
 - Sha1 regressions
 - Fixing assigned Bugs



---------------------------------------------------------------------
In AArch64, some of the integer  operations support “w” constraint
(FP_REGS). For example *addsi3_aarch64 pattern supports it. However, not
all of the integer operations supports it. In the cases where it is
supported,  all the operands have to be  in FP_REGS and it will not work
if we have one operand in FP_REGS and other in GENERAL_REGS.

If there is an allocno  whose pseudo register is used only in
*addsi3_aarch64 insns, it will have low cost for register class FP_REGS
(as in the case of a28 below exacted from an example).  If  the other
pseudo register used in *addsi3_aarch64 (a27 in the example below) is
also used in instructions (rorsi3_insn in the exaple below) that does
not support “w” constraint, there is going to be a cost involved in
moving it from  FP_REGS to  GENERAL_REGS (or other way)

Currently IRA dosent seems to be considering  this dependency in
considering this inter dependency in cost calculation.


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