Subzero: Initial implementation of BB Local CSE

tests_lit/llvm2ice_tests/local-cse.ll

+;Tests local-cse on x8632 and x8664
+; RUN: %p2i -i %s --filetype=asm --target x8632 --args -threads=0 \

[Jim Stichnoth, 2016/05/23 16:52:57]

1. Instead of "--filetype=asm", use "--filetype=obj --disassemble".  Otherwise
the test will fail in a MINIMAL build (or more generally, a NODUMP build)
because only filetype=obj is supported there.

2. No need to specify -threads=0 here.  In fact, using the default (threads=2)
is encouraged in order to draw out non-determinism that might have snuck in.

3. Once you add "--disassemble", you will need to modify the CHECK lines to
follow Intel asm syntax, rather than AT&T syntax.  (i.e., s/addl/add/ )

[manasijm, 2016/05/23 23:13:30]

Done.

+; RUN: -O2 -enable-experimental | FileCheck --check-prefix X8632EXP %s
+
+; RUN: %p2i -i %s --filetype=asm --target x8632 --args -threads=0 \
+; RUN: -O2 | FileCheck --check-prefix X8632 %s
+
+; RUN: %p2i -i %s --filetype=asm --target x8664 --args -threads=0 \
+; RUN: -O2 -enable-experimental | FileCheck --check-prefix X8664EXP %s
+
+; RUN: %p2i -i %s --filetype=asm --target x8664 --args -threads=0 \
+; RUN: -O2 | FileCheck --check-prefix X8664 %s
+
+
+define internal i32 @local_cse_test(i32 %a, i32 %b) {
+entry:
+  %add1 = add i32 %b, %a
+  %add2 = add i32 %b, %a
+  %add3 = add i32 %add1, %add2
+  ret i32 %add3
+}
+; X8632: addl

[Jim Stichnoth, 2016/05/23 16:52:57]

There is a lot of repetition of fixed patterns in the test output.  This can be
mitigated by using multiple --check-prefix arguments in the RUN command.  Below,
I've made this modification to the test.  "X8632" represents the output that is
always there for target=x8632, regardless of -enable-experimental.  "X8632EXP"
output should be there when using -enable-experimental, and "X8632NOEXP" when
not using it.

Also, you might consider further simplifying the test patterns since x8632 and
x8664 output are identical with respect to what's being tested.  I.e., just use
"X86" instead of "X8632" and "X8664".

; Tests local-cse on x8632 and x8664

; RUN: %p2i -i %s --filetype=obj --disassemble --target x8632 --args \
; RUN: -O2 -enable-experimental | FileCheck --check-prefix=X8632 --check-prefix
X8632EXP %s

; RUN: %p2i -i %s --filetype=obj --disassemble --target x8632 --args \
; RUN: -O2 | FileCheck --check-prefix=X8632 --check-prefix X8632NOEXP %s

; RUN: %p2i -i %s --filetype=obj --disassemble --target x8664 --args \
; RUN: -O2 -enable-experimental | FileCheck --check-prefix=X8664 --check-prefix
X8664EXP %s

; RUN: %p2i -i %s --filetype=obj --disassemble --target x8664 --args \
; RUN: -O2 | FileCheck --check-prefix=X8664 --check-prefix X8664NOEXP %s


define internal i32 @local_cse_test(i32 %a, i32 %b) {
entry:
  %add1 = add i32 %b, %a
  %add2 = add i32 %b, %a
  %add3 = add i32 %add1, %add2
  ret i32 %add3
}
; X8632: add
; X8632: add
; X8632NOEXP: add
; X8632EXP-NOT: add
; X8632: ret

; X8664: add
; X8664: add
; X8664NOEXP: add
; X8664EXP-NOT: add
; X8664: ret

[manasijm, 2016/05/23 23:13:30]

Done.

+; X8632: addl
+; X8632: addl
+; X8632: ret
+
+; X8632EXP: addl
+; X8632EXP: addl
+; X8632EXP-NOT: addl
+; X8632EXP: ret
+
+; X8664: addl
+; X8664: addl
+; X8664: addl
+; X8664: ret
+
+; X8664EXP: addl
+; X8664EXP: addl
+; X8664EXP-NOT: addl
+; X8664EXP: ret
+

[Jim Stichnoth, 2016/05/23 16:52:57]

Remove trailing whitespace (i.e. blank line at the end of file) to keep git
happy.

[manasijm, 2016/05/23 23:13:30]

Done.