based on instruction complexity
The order that tablegen fast-isel instruction code is generated is
currently based on the text of the predicate (using string
less-than). This patch changes this to instead use the instruction
complexity. Because the complexities are not unique a C++ multimap is
used instead of a map.
This fixes the problem where code with no predicate always comes out
first (the empty string always compares as less than all other
strings) thus making the code with predicates dead code. See the FMUL
code in PPCFastISel.cpp for an example. It also more closely matches
the normal codegen ordering. Some error checking in the tablegen
fast-isel code is fixed as well.
Patch by Bill Seurer.
llvm-svn: 222038
FastISel has a fixed set of virtual functions that are overridden by the
tablegen-generated code for each target. These functions are distinguished by
the kinds of operands, e.g., register + immediate = "ri". The FastISel emitter
has been blindly emitting functions with different combinations of operand
kinds, even for combinations that are completely unused by FastISel, e.g.,
"fastEmit_rrr". Change to filter out functions that will be irrelevant for
FastISel and do not bother generating the code for them. Also add explicit
"override" keywords for the virtual functions that are overridden.
llvm-svn: 218838
This is the final round of renaming. This changes tblgen to emit lower-case
function names for FastEmitInst_* and FastEmit_*, and updates all its uses
in the source code.
Reviewed by Eric
llvm-svn: 217075
Currently the fast-isel table generator recognizes registers, register
classes, and immediates for source pattern operands. ValueType
operands are not recognized. This is not a problem for existing
targets with fast-isel support, but will not work for targets like
PowerPC and SPARC that use types in source patterns.
The proposed patch allows ValueType operands and treats them in the
same manner as register classes. There is no convenient way to map
from a ValueType to a register class, but there's no need to do so.
The table generator already requires that all types in the source
pattern be identical, and we know the register class of the output
operand already. So we just assign that register class to any
ValueType operands we encounter.
No functional effect on existing targets. Testing deferred until the
PowerPC target implements fast-isel.
llvm-svn: 182512
Most places can use PrintFatalError as the unwinding mechanism was not
used for anything other than printing the error. The single exception
was CodeGenDAGPatterns.cpp, where intermediate errors during type
resolution were ignored to simplify incremental platform development.
This use is replaced by an error flag in TreePattern and bailout earlier
in various places if it is set.
llvm-svn: 166712
Some of these dyn_cast<>'s would be better phrased as isa<> or cast<>.
That will happen in a future patch.
There are also two dyn_cast_or_null<>'s slipped in instead of
dyn_cast<>'s, since they were causing crashes with just dyn_cast<>.
llvm-svn: 165646
There are some that I didn't remove this round because they looked like
obvious stubs. There are dead variables in gtest too, they should be
fixed upstream.
llvm-svn: 158090
/// FastEmit_f - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// floating-point immediate operand be emitted.
virtual unsigned FastEmit_f(MVT VT,
MVT RetVT,
unsigned Opcode,
const ConstantFP *FPImm);
Currently, it emits an accidentally overloaded version without the const on the
ConstantFP*. This doesn't affect anything in the tree, since nothing causes that
method to be autogenerated, but I have been playing with some ARM TableGen
refactorings that hit this problem.
llvm-svn: 147727
Manage Inits in a FoldingSet. This provides several benefits:
- Memory for Inits is properly managed
- Duplicate Inits are folded into Flyweights, saving memory
- It enforces const-correctness, protecting against certain classes
of bugs
The above benefits allow Inits to be used in more contexts, which in
turn provides more dynamism to TableGen. This enhanced capability
will be used by the AVX code generator to a fold common patterns
together.
llvm-svn: 134907
the generated FastISel. X86 doesn't need to generate code to match ADD16ri8
since ADD16ri will do just fine. This is a small codesize win in the generated
instruction selector.
llvm-svn: 129692
value constraints on them (when defined as ImmLeaf's). This is particularly important
for X86-64, where almost all reg/imm instructions take a i64immSExt32 immediate operand,
which has a value constraint. Before this patch we ended up iseling the examples into
such amazing code as:
movabsq $7, %rax
imulq %rax, %rdi
movq %rdi, %rax
ret
now we produce:
imulq $7, %rdi, %rax
ret
This dramatically shrinks the generated code at -O0 on x86-64.
llvm-svn: 129691
2. implement rdar://9289501 - fast isel should fold trivial multiplies to shifts
3. teach tblgen to handle shift immediates that are different sizes than the
shifted operands, eliminating some code from the X86 fast isel backend.
4. Have FastISel::SelectBinaryOp use (the poorly named) FastEmit_ri_ function
instead of FastEmit_ri to simplify code.
llvm-svn: 129666
- Check getBytesToPopOnReturn().
- Eschew ST0 and ST1 for return values.
- Fix the PIC base register initialization so that it doesn't ever
fail to end up the top of the entry block.
llvm-svn: 108039
U utils/TableGen/FastISelEmitter.cpp
--- Reverse-merging r107943 into '.':
U test/CodeGen/X86/fast-isel.ll
U test/CodeGen/X86/fast-isel-loads.ll
U include/llvm/Target/TargetLowering.h
U include/llvm/Support/PassNameParser.h
U include/llvm/CodeGen/FunctionLoweringInfo.h
U include/llvm/CodeGen/CallingConvLower.h
U include/llvm/CodeGen/FastISel.h
U include/llvm/CodeGen/SelectionDAGISel.h
U lib/CodeGen/LLVMTargetMachine.cpp
U lib/CodeGen/CallingConvLower.cpp
U lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
U lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
U lib/CodeGen/SelectionDAG/FastISel.cpp
U lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
U lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
U lib/CodeGen/SelectionDAG/InstrEmitter.cpp
U lib/CodeGen/SelectionDAG/TargetLowering.cpp
U lib/Target/XCore/XCoreISelLowering.cpp
U lib/Target/XCore/XCoreISelLowering.h
U lib/Target/X86/X86ISelLowering.cpp
U lib/Target/X86/X86FastISel.cpp
U lib/Target/X86/X86ISelLowering.h
llvm-svn: 107987
around everywhere, and also give it an InsertPt member, to enable isel
to operate at an arbitrary position within a block, rather than just
appending to a block.
llvm-svn: 107791
Bill Schmidt