Ahmed Bougacha 4d962b05ca [X86] Improve mul w/ overflow codegen, to MUL8+SETO. ... Currently, @llvm.smul.with.overflow.i8 expands to 9 instructions, where 3 are really needed. This adds X86ISD::UMUL8/SMUL8 SD nodes, and custom lowers them to MUL8/IMUL8 + SETO. i8 is a special case because there is no two/three operand variants of (I)MUL8, so the first operand and return value need to go in AL/AX. Also, we can't write patterns for these instructions: TableGen refuses patterns where output operands don't match SDNode results. In this case, instructions where the output operand is an implicitly defined register. A related special case (and FIXME) exists for MUL8 (X86InstrArith.td): // FIXME: Used for 8-bit mul, ignore result upper 8 bits. // This probably ought to be moved to a def : Pat<> if the // syntax can be accepted. [(set AL, (mul AL, GR8:$src)), (implicit EFLAGS)] Ideally, these go away with UMUL8, but we still need to improve TableGen support of implicit operands in patterns. Before this change: movsbl %sil, %eax movsbl %dil, %ecx imull %eax, %ecx movb %cl, %al sarb $7, %al movzbl %al, %eax movzbl %ch, %esi cmpl %eax, %esi setne %al After: movb %dil, %al imulb %sil seto %al Also, remove a made-redundant testcase for PR19858, and enable more FastISel ALU-overflow tests for SelectionDAG too. Differential Revision: http://reviews.llvm.org/D5809 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220516 91177308-0d34-0410-b5e6-96231b3b80d8		2014-10-23 21:55:31 +00:00
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Analysis	[InstSimplify] Support constant folding to vector of pointers	2014-10-22 12:18:48 +00:00
AsmParser
Bitcode	clang-format two code snippets to make the next patch easy to read.	2014-10-23 15:20:05 +00:00
CodeGen	DebugInfo: Remove DwarfDebug::addCurrentFnArgument declaration now that it's moved to DwarfFile.	2014-10-23 21:53:17 +00:00
DebugInfo	[dwarfdump] Dump DW_AT_ranges values inline in the debug_info dump.	2014-10-23 04:08:34 +00:00
ExecutionEngine	[MCJIT] Make repeat calls to MCJIT::getPointerToFunction for declarations safe.	2014-10-22 23:18:42 +00:00
IR	Revert "Don't count inreg params when mangling fastcall functions"	2014-10-23 17:50:42 +00:00
IRReader
LineEditor
Linker
LTO
MC	Attempt to fix the build after r220439	2014-10-22 22:46:05 +00:00
Object	Update llvm-objdump’s Mach-O symbolizer code for Objective-C references.	2014-10-23 19:37:31 +00:00
Option
ProfileData
Support	Modernize doxygen comments in Support/Dwarf.h	2014-10-23 04:08:38 +00:00
TableGen
Target	[X86] Improve mul w/ overflow codegen, to MUL8+SETO.	2014-10-23 21:55:31 +00:00
Transforms	Handle sqrt() shrinking in SimplifyLibCalls like any other call	2014-10-23 21:52:45 +00:00
CMakeLists.txt
LLVMBuild.txt
Makefile