Legalize div/idiv operands to avoid immediates.

Legalize div/idiv operands to avoid immediates.

The div/idiv instruction operand must be a register or memory.

BUG=none
R=stichnot@chromium.org

Committed: https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-subzero.git;a=commit;h=70d6883

[Jim Stichnoth, 2014-06-17 05:35:06]

LGTM, with small nit.

Also, in the CL description, "intermediates" --> "immediates"?

https://codereview.chromium.org/339643003/diff/20001/src/IceTargetLoweringX86...
File src/IceTargetLoweringX8632.cpp (right):

https://codereview.chromium.org/339643003/diff/20001/src/IceTargetLoweringX86...
src/IceTargetLoweringX8632.cpp:1139: Src1 = legalize(Src1, Legal_Reg |
Legal_Mem, true);
It's hard to wrap my head around the AllowOverlap logic in legalize(), but I'm
pretty sure its value will be ignored if Legal_Mem is set and RegNum is not
specified.  Assuming this is true, it would be better to leave AllowOverlap to
be the default false value.  Here and below.  (Of course, the example this was
copied from is probably "wrong" as well...)

[jvoung (off chromium), 2014-06-17 16:11:08]

https://codereview.chromium.org/339643003/diff/20001/src/IceTargetLoweringX86...
File src/IceTargetLoweringX8632.cpp (right):

https://codereview.chromium.org/339643003/diff/20001/src/IceTargetLoweringX86...
src/IceTargetLoweringX8632.cpp:1139: Src1 = legalize(Src1, Legal_Reg |
Legal_Mem, true);
On 2014/06/17 05:35:06, stichnot wrote:
> It's hard to wrap my head around the AllowOverlap logic in legalize(), but I'm
> pretty sure its value will be ignored if Legal_Mem is set and RegNum is not
> specified.  Assuming this is true, it would be better to leave AllowOverlap to
> be the default false value.  Here and below.  (Of course, the example this was
> copied from is probably "wrong" as well...)

Done. Yeah it looks like it will be ignored in this case, where Legal_Mem is set
and RegNum is not specified. Changed to default arguments.

[jvoung (off chromium), 2014-06-17 17:02:50]

Committed patchset #3 manually as r70d6883 (presubmit successful).