From: Oscar Fuentes <ofv@wanadoo.es>
Date: Fri, 21 Nov 2008 00:18:45 +0000 (+0000)
Subject: CMake: Do not rebuild the world when tblgen changes but the .inc files
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=beb7a05086e1a4eba9a4a76fd830ce84f15cef43;p=oota-llvm.git

CMake: Do not rebuild the world when tblgen changes but the .inc files
it produces are not affected by the change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59763 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/cmake/modules/TableGen.cmake b/cmake/modules/TableGen.cmake
index 7836c4e4928..bea369f4c61 100644
--- a/cmake/modules/TableGen.cmake
+++ b/cmake/modules/TableGen.cmake
@@ -4,9 +4,16 @@
 
 macro(tablegen ofn)
   file(GLOB all_tds "*.td")
+  add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.tmp
+    COMMAND ${LLVM_TABLEGEN} ${ARGN} -I ${CMAKE_CURRENT_SOURCE_DIR}
+    -I ${LLVM_MAIN_SRC_DIR}/lib/Target -I ${LLVM_MAIN_INCLUDE_DIR}
+    ${CMAKE_CURRENT_SOURCE_DIR}/${LLVM_TARGET_DEFINITIONS} -o ${ofn}.tmp
+    DEPENDS ${LLVM_TABLEGEN} ${all_tds}
+    COMMENT "Building ${ofn}.tmp..."
+    )
   add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${ofn}
-    COMMAND ${LLVM_TABLEGEN} ${ARGN} -I ${CMAKE_CURRENT_SOURCE_DIR} -I ${LLVM_MAIN_SRC_DIR}/lib/Target -I ${LLVM_MAIN_INCLUDE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/${LLVM_TARGET_DEFINITIONS} -o ${ofn}
-    DEPENDS tblgen ${all_tds}
+    COMMAND ${CMAKE_COMMAND} -E copy_if_different ${ofn}.tmp ${ofn}
+    DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.tmp
     COMMENT "Building ${ofn}..."
     )
   set(TABLEGEN_OUTPUT ${TABLEGEN_OUTPUT} ${CMAKE_CURRENT_BINARY_DIR}/${ofn})