[builtins] Move X86 common files to a subdirectory

[kongyi]

Summary

With 8ea148dc0cbf, we can clean up the root directory of crt builtins by moving x86 common source files to a subdirectory.

[delcypher]

@kongyi Hmm we have both x86_common/floatdixf.c and x86_64/floatdixf.c. I think both x86_64h_SOURCES and x86_64_SOURCES will end up with both x86_common/floatdixf.c and x86_64/floatdixf.c due to...

set(x86_64h_SOURCES ${x86_64h_SOURCES} ${x86_ARCH_SOURCES})
set(x86_64_SOURCES ${x86_64_SOURCES} ${x86_ARCH_SOURCES})

I don't think the filtering algorithm (removing generic builtin implementations in favour of architecture specific implementations) handles this case. Due to both sources being in sub directories they are considered to both be architecture specific implementations.
If I'm right it should mean that with this patch running ninja check-builtins should result in an error due to me relanding 23a33d450b9a426eae7094b16472f8a51fb5488a, i.e. when lit runs we should detect that there is more than one implementation of floatdixf.

Could you check this?

[kongyi]

In D69688#1730803, @delcypher wrote:

@kongyi Hmm we have both x86_common/floatdixf.c and x86_64/floatdixf.c. I think both x86_64h_SOURCES and x86_64_SOURCES will end up with both x86_common/floatdixf.c and x86_64/floatdixf.c due to...

set(x86_64h_SOURCES ${x86_64h_SOURCES} ${x86_ARCH_SOURCES})
set(x86_64_SOURCES ${x86_64_SOURCES} ${x86_ARCH_SOURCES})

I don't think the filtering algorithm (removing generic builtin implementations in favour of architecture specific implementations) handles this case. Due to both sources being in sub directories they are considered to both be architecture specific implementations.
If I'm right it should mean that with this patch running ninja check-builtins should result in an error due to me relanding 23a33d450b9a426eae7094b16472f8a51fb5488a, i.e. when lit runs we should detect that there is more than one implementation of floatdixf.

Could you check this?

Ah, I didn't notice this... Let me rework the patch to fix this.

compiler-rt/lib/builtins/CMakeLists.txt

if (NOT FUCHSIA)
   set(GENERIC_SOURCES
     ${GENERIC_SOURCES}
     clear_cache.c
   )
 endif()
 
 # These sources work on all x86 variants, but only x86 variants.
 set(x86_ARCH_SOURCES
-  cpu_model.c
-  divxc3.c
-  fixxfdi.c
-  fixxfti.c
-  fixunsxfdi.c
-  fixunsxfsi.c
-  fixunsxfti.c
-  floatdixf.c
-  floattixf.c
-  floatundixf.c
-  floatuntixf.c
-  mulxc3.c
-  powixf2.c
+  x86_common/cpu_model.c
+  x86_common/divxc3.c
+  x86_common/fixxfdi.c
+  x86_common/fixxfti.c
+  x86_common/fixunsxfdi.c
+  x86_common/fixunsxfsi.c
+  x86_common/fixunsxfti.c
+  x86_common/floatdixf.c
+  x86_common/floattixf.c
+  x86_common/floatundixf.c
+  x86_common/floatuntixf.c
+  x86_common/mulxc3.c
+  x86_common/powixf2.c
 )
 
 if (NOT MSVC)
   set(x86_64_SOURCES
     ${GENERIC_TF_SOURCES}
     x86_64/floatdidf.c
     x86_64/floatdisf.c
     x86_64/floatdixf.c