Duncan Sands bbd03677ee Add a new codegen pass that normalizes dwarf exception handling ... code in preparation for code generation. The main thing it does is handle the case when eh.exception calls (and, in a future patch, eh.selector calls) are far away from landing pads. Right now in practice you only find eh.exception calls close to landing pads: either in a landing pad (the common case) or in a landing pad successor, due to loop passes shifting them about. However future exception handling improvements will result in calls far from landing pads: (1) Inlining of rewinds. Consider the following case: In function @f: ... invoke @g to label %normal unwind label %unwinds ... unwinds: %ex = call i8* @llvm.eh.exception() ... In function @g: ... invoke @something to label %continue unwind label %handler ... handler: %ex = call i8* @llvm.eh.exception() ... perform cleanups ... "rethrow exception" Now inline @g into @f. Currently this is turned into: In function @f: ... invoke @something to label %continue unwind label %handler ... handler: %ex = call i8* @llvm.eh.exception() ... perform cleanups ... invoke "rethrow exception" to label %normal unwind label %unwinds unwinds: %ex = call i8* @llvm.eh.exception() ... However we would like to simplify invoke of "rethrow exception" into a branch to the %unwinds label. Then %unwinds is no longer a landing pad, and the eh.exception call there is then far away from any landing pads. (2) Using the unwind instruction for cleanups. It would be nice to have codegen handle the following case: invoke @something to label %continue unwind label %run_cleanups ... handler: ... perform cleanups ... unwind This requires turning "unwind" into a library call, which necessarily takes a pointer to the exception as an argument (this patch also does this unwind lowering). But that means you are using eh.exception again far from a landing pad. (3) Bugpoint simplifications. When bugpoint is simplifying exception handling code it often generates eh.exception calls far from a landing pad, which then causes codegen to assert. Bugpoint then latches on to this assertion and loses sight of the original problem. Note that it is currently rare for this pass to actually do anything. And in fact it normally shouldn't do anything at all given the code coming out of llvm-gcc! But it does fire a few times in the testsuite. As far as I can see this is almost always due to the LoopStrengthReduce codegen pass introducing pointless loop preheader blocks which are landing pads and only contain a branch to another block. This other block contains an eh.exception call. So probably by tweaking LoopStrengthReduce a bit this can be avoided. llvm-svn: 72276		2009-05-22 20:36:31 +00:00
..
ADT	Add llvm::triple constructor from arch, vendor, os strings, and recognize	2009-05-22 02:24:11 +00:00
Analysis	Fix broken logic in DominatorTreeBase::Split. Part of PR4238.	2009-05-21 21:47:54 +00:00
Assembly	add a #include to improve portability to windows, as requested by	2009-03-09 05:10:08 +00:00
Bitcode	give bitstreamreader an API to ignore names for blocks/records,	2009-04-27 20:04:08 +00:00
CodeGen	Add a new codegen pass that normalizes dwarf exception handling	2009-05-22 20:36:31 +00:00
CompilerDriver	-write-graph now can be used with -o.	2009-03-27 12:57:14 +00:00
Config	Forgot this file in my last commit.	2009-05-19 22:25:55 +00:00
Debugger
ExecutionEngine	Allow the JIT ExecutionEngine to report details about the generated machine code.	2009-05-18 21:06:40 +00:00
Support	Add an accessor method to return the insertion point.	2009-05-20 21:45:41 +00:00
System	Use DataTypes.h instead of stdint.h.	2009-05-21 00:48:13 +00:00
Target	Run code placement optimization for targets that want it (arm and x86 for now).	2009-05-13 21:42:09 +00:00
Transforms	Re-apply 70645, converting ScalarEvolution to use	2009-05-04 22:30:44 +00:00
AbstractTypeUser.h	Another attempt at fixing PR2975.	2009-04-07 17:23:02 +00:00
Argument.h
Attributes.h
AutoUpgrade.h
BasicBlock.h	Revert r67844. This fixes the llvm-gcc-4.2 build on Darwin.	2009-03-27 18:37:13 +00:00
CallGraphSCCPass.h
CallingConv.h
CMakeLists.txt	CMake: Have generated Xcode projects also contain the LLVM header files.	2009-04-01 15:40:21 +00:00
Constant.h	Clearify local/global relocations wording	2009-03-30 17:38:00 +00:00
Constants.h	Add a getAlignOf helper for getting the ABI alignment of a	2009-05-21 15:52:21 +00:00
DerivedTypes.h	80-column violation.	2009-02-14 08:41:25 +00:00
Function.h	Revert r67844. This fixes the llvm-gcc-4.2 build on Darwin.	2009-03-27 18:37:13 +00:00
GlobalAlias.h
GlobalValue.h	Add a new "available_externally" linkage type. This is intended	2009-04-13 05:44:34 +00:00
GlobalVariable.h	Factorize out a concept - no functionality change.	2009-03-21 21:27:31 +00:00
InlineAsm.h	Model inline asm constraint which ties an input to an output register as machine operand TIED_TO constraint. This eliminated the need to pre-allocate registers for these. This also allows register allocator can eliminate the unneeded copies.	2009-03-23 08:01:15 +00:00
InstrTypes.h	80-column violations.	2009-02-09 17:11:05 +00:00
Instruction.def
Instruction.h	Allow readonly functions to unwind exceptions. Teach	2009-05-06 06:49:50 +00:00
Instructions.h	Remove getType() overrides for ExtractValueInst and InsertValueInst.	2009-05-18 18:46:57 +00:00
IntrinsicInst.h	change the MemIntrinsic get/setAlignment method to take an unsigned	2009-03-08 03:59:00 +00:00
Intrinsics.h	Added support to have TableGen provide information if an intrinsic (core	2009-02-24 23:17:49 +00:00
Intrinsics.td	Update the names of the exception handling sjlj instrinsics to	2009-05-14 00:46:35 +00:00
IntrinsicsAlpha.td
IntrinsicsARM.td
IntrinsicsCellSPU.td
IntrinsicsPowerPC.td
IntrinsicsX86.td	ADDS{D|S}rr_Int and MULS{D|S}rr_Int are not commutable. The users of these intrinsics expect the high bits will not be modified.	2009-02-26 03:12:02 +00:00
IntrinsicsXCore.td
LinkAllPasses.h	Add a liveness analysis pass for LLVM IR values. This computes	2009-03-19 17:29:04 +00:00
LinkAllVMCore.h
Linker.h
MDNode.h	Needed #includes. Thanks Fritz van Bommel!	2009-05-10 23:27:41 +00:00
Module.h	"ghostify" the ilist<Function> sentinel	2009-03-27 22:28:33 +00:00
ModuleProvider.h
OperandTraits.h	Give Op<N>() AppleScript-like semantics, i.e. for negative N it indexes relative to op_end.	2009-03-10 23:02:13 +00:00
Pass.h	Remove dead code.	2009-04-01 21:27:08 +00:00
PassAnalysisSupport.h	Clean up pass manager cache after each run.	2009-04-01 22:34:41 +00:00
PassManager.h
PassManagers.h	Clean up pass manager cache after each run.	2009-04-01 22:34:41 +00:00
PassSupport.h	remove a deprecated interface that was pretty useless	2009-03-02 12:42:07 +00:00
SymbolTableListTraits.h	simplify the way how traits get hold of the symbol table	2009-03-07 12:33:24 +00:00
Type.h	Add a new Type::getPointerTo method, which is shorthand for	2009-04-10 06:42:02 +00:00
TypeSymbolTable.h	Fixed spelling.	2009-04-01 16:13:29 +00:00
Use.h	Add a comment to refer to the section of the programmer's manual that explains what the pointer tagging in Use is for.	2009-04-30 23:28:50 +00:00
User.h	Fix the Win32 VS2008 build:	2009-03-19 23:26:52 +00:00
Value.h	Add support for embedded metadata to LLVM. This introduces two new types of	2009-04-04 07:22:01 +00:00
ValueSymbolTable.h