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LLVM backend for 6502
A setting in MCAsmInfo defines the "assembler dialect" to use. This is used by common code to choose between alternatives in a multi-alternative GNU inline asm statement like the following: __asm__ ("{sfe|subfe} %0,%1,%2" : "=r" (out) : "r" (in1), "r" (in2)); The meaning of these dialects is platform specific, and GCC defines those for PowerPC to use dialect 0 for old-style (POWER) mnemonics and 1 for new-style (PowerPC) mnemonics, like in the example above. To be compatible with inline asm used with GCC, LLVM ought to do the same. Specifically, this means we should always use assembler dialect 1 since old-style mnemonics really aren't supported on any current platform. However, the current LLVM back-end uses: AssemblerDialect = 1; // New-Style mnemonics. in PPCMCAsmInfoDarwin, and AssemblerDialect = 0; // Old-Style mnemonics. in PPCLinuxMCAsmInfo. The Linux setting really isn't correct, we should be using new-style mnemonics everywhere. This is changed by this commit. Unfortunately, the setting of this variable is overloaded in the back-end to decide whether or not we are on a Darwin target. This is done in PPCInstPrinter (the "SyntaxVariant" is initialized from the MCAsmInfo AssemblerDialect setting), and also in PPCMCExpr. Setting AssemblerDialect to 1 for both Darwin and Linux no longer allows us to make this distinction. Instead, this patch uses the MCSubtargetInfo passed to createPPCMCInstPrinter to distinguish Darwin targets, and ignores the SyntaxVariant parameter. As to PPCMCExpr, this patch adds an explicit isDarwin argument that needs to be passed in by the caller when creating a target MCExpr. (To do so this patch implicitly also reverts commit 184441.) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185858 91177308-0d34-0410-b5e6-96231b3b80d8 |
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bindings | ||
cmake | ||
docs | ||
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include | ||
lib | ||
projects | ||
runtime | ||
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tools | ||
unittests | ||
utils | ||
.arcconfig | ||
.gitignore | ||
CMakeLists.txt | ||
CODE_OWNERS.TXT | ||
configure | ||
CREDITS.TXT | ||
LICENSE.TXT | ||
llvm.spec.in | ||
LLVMBuild.txt | ||
Makefile | ||
Makefile.common | ||
Makefile.config.in | ||
Makefile.rules | ||
README.txt |
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