Kevin Enderby a89594947e Improve the time it takes to generating dwarf for assembly source files ... that have been run through the 'C' pre-processor. The implementation of SrcMgr.FindLineNumber() is slow but OK if it uses its cache when called multiple times with an SMLoc that is forward of the previous call. In the case of generating dwarf for assembly source files that have been run through the 'C' pre-processor we need to calculate the logical line number based on the last parsed cpp hash file line comment. And the current code calls SrcMgr.FindLineNumber() twice to do this causing its cache not to work and results in very slow compile times: % time /Volumes/SandBox/build-llvm/Debug+Asserts/bin/llvm-mc -triple thumbv7-apple-ios -filetype=obj -o /tmp/x.o mscorlib.dll.E -g 672.542u 0.299s 11:13.15 99.9% 0+0k 0+2io 2106pf+0w So we save the info from the last parsed cpp hash file line comment to avoid making the second call to SrcMgr.FindLineNumber() most times and end up with compile times like: % time /Volumes/SandBox/build-llvm/Debug+Asserts/bin/llvm-mc -triple thumbv7-apple-ios -filetype=obj -o /tmp/x.o mscorlib.dll.E -g 3.404u 0.104s 0:03.80 92.1% 0+0k 0+3io 2105pf+0w rdar://14156934 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184592 91177308-0d34-0410-b5e6-96231b3b80d8		2013-06-21 20:51:39 +00:00
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AsmLexer.cpp
AsmParser.cpp	Improve the time it takes to generating dwarf for assembly source files	2013-06-21 20:51:39 +00:00
CMakeLists.txt
COFFAsmParser.cpp
DarwinAsmParser.cpp
ELFAsmParser.cpp
LLVMBuild.txt
Makefile
MCAsmLexer.cpp
MCAsmParser.cpp
MCAsmParserExtension.cpp
MCTargetAsmParser.cpp