Commit Graph

308 Commits

Author SHA1 Message Date
Craig Topper 2fa1436206 [IR][CodeGen] Remove dependency on EVT from IR/Function.cpp. Move EVT to CodeGen layer.
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.

The previous code converted a Type* to EVT and then called getEVTString. This was only expected to handle the primitive types from Type*. Since there only a few primitive types, we can just print them as strings directly.

Differential Revision: https://reviews.llvm.org/D45017

llvm-svn: 328806
2018-03-29 17:21:10 +00:00
David Blaikie b3f471a4bd Remove some unused includes to fix layering.
llvm-svn: 328745
2018-03-29 00:29:45 +00:00
David Blaikie 36a0f226b1 Fix layering by moving ValueTypes.h from CodeGen to IR
ValueTypes.h is implemented in IR already.

llvm-svn: 328397
2018-03-23 23:58:31 +00:00
Yonghong Song 82bf8bcb4f bpf: Enhance debug information for peephole optimization passes
Add more debug information for peephole optimization passes.

These would only be enabled for debug version binary and could help
analyzing why some optimization opportunities were missed.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 327371
2018-03-13 06:47:07 +00:00
Yonghong Song e91802f336 bpf: New post-RA peephole optimization pass to eliminate bad RA codegen
This new pass eliminate identical move:

  MOV rA, rA

This is particularly possible to happen when sub-register support
enabled. The special type cast insn MOV_32_64 involves different
register class on src (i32) and dst (i64), RA could generate useless
instruction due to this.

This pass also could serve as the bast for further post-RA optimization.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 327370
2018-03-13 06:47:06 +00:00
Yonghong Song 80b882ecc5 bpf: Don't expand BSWAP on i32, promote it
Currently, there is no ALU32 bswap support in eBPF ISA.

BSWAP on i32 was set to EXPAND which would need about eight instructions
for single BSWAP.

It would be more efficient to promote it to i64, then doing BSWAP on i64.
For eBPF programs, most of the promotion are zero extensions which are
likely be elimiated later by peephole optimizations.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 327369
2018-03-13 06:47:05 +00:00
Yonghong Song 1d28a759d9 bpf: Support subregister definition check on PHI node
This patch relax the subregister definition check on Phi node.
Previously, we just cancel the optimizatoin when the definition is Phi
node while actually we could further check the definitions of incoming
parameters of PHI node.

This helps catch more elimination opportunities.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 327368
2018-03-13 06:47:04 +00:00
Yonghong Song c88bcdec43 bpf: Extends zero extension elimination beyond comparison instructions
The current zero extension elimination was restricted to operands of
comparison. It actually could be extended to more cases.

For example:

  int *inc_p (int *p, unsigned a)
  {
    return p + a;
  }

'a' will be promoted to i64 during addition, and the zero extension could
be eliminated as well.

For the elimination optimization, it should be much better to start
recognizing the candidate sequence from the SRL instruction instead of J*
instructions.

This patch makes it an generic zero extension elimination pass instead of
one restricted with comparison.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 327367
2018-03-13 06:47:03 +00:00
Yonghong Song 905d13c123 bpf: J*_RR should check both operands
There is a mistake in current code that we "break" out the optimization
when the first operand of J*_RR doesn't qualify the elimination. This
caused some elimination opportunities missed, for example the one in the
testcase.

The code should just fall through to handle the second operand.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 327366
2018-03-13 06:47:02 +00:00
Yonghong Song 89e47ac671 bpf: Tighten subregister definition check
The current subregister definition check stops after the MOV_32_64
instruction.

This means we are thinking all the following instruction sequences
are safe to be eliminated:

  MOV_32_64 rB, wA
  SLL_ri    rB, rB, 32
  SRL_ri    rB, rB, 32

However, this is *not* true. The source subregister wA of MOV_32_64 could
come from a implicit truncation of 64-bit register in which case the high
bits of the 64-bit register is not zeroed, therefore we can't eliminate
above sequence.

For example, for i32_val, we shouldn't do the elimination:

  long long bar ();

  int foo (int b, int c)
  {
    unsigned int i32_val = (unsigned int) bar();

    if (i32_val < 10)
      return b;
    else
      return c;
  }

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 327365
2018-03-13 06:47:00 +00:00
Yonghong Song 03e1c8b8f9 bpf: introduce -mattr=dwarfris to disable DwarfUsesRelocationsAcrossSections
Commit e4507fb8c94b ("bpf: disable DwarfUsesRelocationsAcrossSections")
disables MCAsmInfo DwarfUsesRelocationsAcrossSections unconditionally
so that dwarf will not use cross section (between dwarf and symbol table)
relocations. This new debug format enables pahole to dump structures
correctly as libdwarves.so does not have BPF backend support yet.

This new debug format, however, breaks bcc (https://github.com/iovisor/bcc)
source debug output as llvm in-memory Dwarf support has some issues to
handle it. More specifically, with DwarfUsesRelocationsAcrossSections
disabled, JIT compiler does not generate .debug_abbrev and Dwarf
DIE (debug info entry) processing is not happy about this.

This patch introduces a new flag -mattr=dwarfris
(dwarf relocation in section) to disable DwarfUsesRelocationsAcrossSections.
DwarfUsesRelocationsAcrossSections is true by default.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 326505
2018-03-01 23:04:59 +00:00
Yonghong Song 60fed1fef0 bpf: New optimization pass for eliminating unnecessary i32 promotions
This pass performs peephole optimizations to cleanup ugly code sequences at
MachineInstruction layer.

Currently, the only optimization in this pass is to eliminate type
promotion
sequences for zero extending 32-bit subregisters to 64-bit registers.

If the compiler could prove the zero extended source come from 32-bit
subregistere then it is safe to erase those promotion sequece, because the
upper half of the underlying 64-bit registers were zeroed implicitly
already.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325991
2018-02-23 23:49:32 +00:00
Yonghong Song ae961bb061 bpf: New decoder namespace for 32-bit subregister load/store
When -mattr=+alu32 passed to the disassembler, use decoder namespace for
32-bit subregister.

This is to disassemble load and store instructions in preferred B format
as described in previous commit:

      w = *(u8 *) (r + off) // BPF_LDX | BPF_B
      w = *(u16 *)(r + off) // BPF_LDX | BPF_H
      w = *(u32 *)(r + off) // BPF_LDX | BPF_W

      *(u8 *) (r + off) = w // BPF_STX | BPF_B
      *(u16 *)(r + off) = w // BPF_STX | BPF_H
      *(u32 *)(r + off) = w // BPF_STX | BPF_W

NOTE: all other instructions should still use the default decoder
      namespace.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325990
2018-02-23 23:49:31 +00:00
Yonghong Song ca31c3bb3f bpf: Enable 32-bit subregister support for -mattr=+alu32
After all those preparation patches, now we could enable 32-bit subregister
support once -mattr=+alu32 specified.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325989
2018-02-23 23:49:30 +00:00
Yonghong Song fcd1e0f625 bpf: Support 32-bit subregister in various InstrInfo hooks
This patch support 32-bit subregister in three InstrInfo hooks, i.e.
copyPhysReg, loadRegFromStackSlot and storeRegToStackSlot,

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325988
2018-02-23 23:49:29 +00:00
Yonghong Song b1a52bd756 bpf: New instruction patterns for 32-bit subregister load and store
The instruction mapping between eBPF/arm64/x86_64 are:

         eBPF              arm64        x86_64
LD1   BPF_LDX | BPF_B       ldrb        movzbl
LD2   BPF_LDX | BPF_H       ldrh        movzwl
LD4   BPF_LDX | BPF_W       ldr         movl

movzbl/movzwl/movl on x86_64 accept 32-bit sub-register, for example %eax,
the same for ldrb/ldrh on arm64 which accept 32-bit "w" register. And
actually these instructions only accept sub-registers. There is no point
to have LD1/2/4 (unsigned) for 64-bit register, because on these arches,
upper 32-bits are guaranteed to be zeroed by hardware or VM, so load into
the smallest available register class is the best choice for maintaining
type information.

For eBPF we should adopt the same philosophy, to change current
format (A):

  r = *(u8 *) (r + off) // BPF_LDX | BPF_B
  r = *(u16 *)(r + off) // BPF_LDX | BPF_H
  r = *(u32 *)(r + off) // BPF_LDX | BPF_W

  *(u8 *) (r + off) = r // BPF_STX | BPF_B
  *(u16 *)(r + off) = r // BPF_STX | BPF_H
  *(u32 *)(r + off) = r // BPF_STX | BPF_W

into B:

  w = *(u8 *) (r + off) // BPF_LDX | BPF_B
  w = *(u16 *)(r + off) // BPF_LDX | BPF_H
  w = *(u32 *)(r + off) // BPF_LDX | BPF_W

  *(u8 *) (r + off) = w // BPF_STX | BPF_B
  *(u16 *)(r + off) = w // BPF_STX | BPF_H
  *(u32 *)(r + off) = w // BPF_STX | BPF_W

There is no change on encoding nor how should they be interpreted,
everything is as it is, load the specified length, write into low bits of
the register then zeroing all remaining high bits.

The only change is their associated register class and how compiler view
them.

Format A still need to be kept, because eBPF LLVM backend doesn't support
sub-registers at default, but once 32-bit subregister is enabled, it should
use format B.

This patch implemented this together with all those necessary extended load
and truncated store patterns.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325987
2018-02-23 23:49:28 +00:00
Yonghong Song 63cf273f55 bpf: Support i32 in getScalarShiftAmountTy method
getScalarShiftAmount method should be implemented for eBPF backend to make
sure shift amount could still get correct type once 32-bit subregisters
support are enabled.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325986
2018-02-23 23:49:26 +00:00
Yonghong Song 59fc805c7e bpf: Support condition comparison on i32
We need to support condition comparison on i32. All these comparisons are
supposed to be combined into BPF_J* instructions which only support i64.

For ISD::BR_CC we need to promote it to i64 first, then do custom lowering.

For ISD::SET_CC, just expand to SELECT_CC like what's been done for i64.

For ISD::SELECT_CC, we also want to do custom lower for i32. However, after
32-bit subregister support enabled, it is possible the comparison operands
are i32 while the selected value are i64, or the comparison operands are
i64 while the selected value are i32. We need to define extra instruction
pattern and support them in custom instruction inserter.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325985
2018-02-23 23:49:25 +00:00
Yonghong Song 219156cff0 bpf: Handle i32 for ALU operations without ISA support
There is no eBPF ISA support for BSWAP, ROTR, ROTL, SREM, SDIVREM, MULHU,
ADDC, ADDE etc on i32.

They could be emulated by other basic BPF_ALU operations, we'd set their
lowering action the same as i64.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325984
2018-02-23 23:49:24 +00:00
Yonghong Song 07a7a41753 bpf: New calling convention for 32-bit subregisters
This patch add new calling conventions to allow GPR32RegClass as valid
register class for arguments and return types.

New calling convention will only be choosen when -mattr=+alu32 specified.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325983
2018-02-23 23:49:23 +00:00
Yonghong Song 42389377d8 bpf: New target attribute "alu32" for 32-bit subregister support
This new attribute aims to control the enablement of 32-bit subregister
support on eBPF backend.

Name the interface as "alu32" is because we in particular want to enable
the generation of BPF_ALU32 instructions by enable subregister support.

This attribute could be used in the following format with llc:

  llc -mtriple=bpf -mattr=[+|-]alu32

It is disabled at default.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325982
2018-02-23 23:49:22 +00:00
Yonghong Song 0252f35362 bpf: Define instruction patterns for extensions and truncations between i32 to i64
For transformations between i32 and i64, if it is explicit signed extension:
  - first cast the operand to i64
  - then use SLL + SRA to finish the extension.

if it is explicit zero extension:
  - first cast the operand to i64
  - then use SLL + SRL to finish the extension.

if it is explicit any extension:
  - just refer to 64-bit register.

if it is explicit truncation:
  - just refer to 32-bit subregister.

NOTE: Some of the zero extension sequences might be unnecessary, they will be
removed by an peephole pass on MachineInstruction layer.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325981
2018-02-23 23:49:21 +00:00
Yonghong Song 3a564a8f6e bpf: Tighten the immediate predication for 32-bit alu instructions
These 32-bit ALU insn patterns which takes immediate as one operand were
initially added to enable AsmParser support, and the AsmMatcher uses "ins"
and "outs" fields to deduct the operand constraint.

However, the instruction selector doesn't work the same as AsmMatcher. The
selector will use the "pattern" field for which we are not setting the
predication for immediate operands correctly.

Without this patch, i32 would eventually means all i32 operands are valid,
both imm and gpr, while these patterns should allow imm only.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325980
2018-02-23 23:49:19 +00:00
Yonghong Song ec84e2f1b0 bpf: Use markSuperRegs to mark reserved registers
markSuperRegs is the canonical helper function used to mark reserved
registers. It could mark any overlapping sub-registers automatically.

Reviewed-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 325979
2018-02-23 23:49:18 +00:00
Yonghong Song 9fdd139b41 bpf: disable DwarfUsesRelocationsAcrossSections
The pahole does not work with BPF backend properly:

  -bash-4.2$ cat test.c
  struct test_t {
    int a;
    int b;
  };
  int test(struct test_t *s) {
    return s->a;
  }
  -bash-4.2$ clang -g -O2 -target bpf -c test.c
  -bash-4.2$ pahole test.o
  struct clang version 7.0.0 (trunk 325446) (llvm/trunk 325464) {
          clang version 7.0.0 (trunk 325446) (llvm/trunk 325464) clang version 7.0.0 (trunk 325446) (llvm/trunk 325464); /*     0     4 */
          clang version 7.0.0 (trunk 325446) (llvm/trunk 325464) clang version 7.0.0 (trunk 325446) (llvm/trunk 325464); /*     4     4 */

          /* size: 8, cachelines: 1, members: 2 */
          /* last cacheline: 8 bytes */
  };
  -bash-4.2$

The reason is that BPF backend is not yet implemented in elfutils backend
  https://github.com/threatstack/elfutils/tree/master/backends
and pahole depends on elfutils for dwarf parsing and resolving relocation.

More specifically, the unsupported relocation in .debug_info for type/member name
against symbol table caused the incorrect result above. The following is
the raw .rel.debug_info for the above example,
  Hex dump of section '.rel.debug_info':
    0x00000000 06000000 00000000 0a000000 0b000000 ................
    0x00000010 0c000000 00000000 0a000000 01000000 ................
    0x00000020 12000000 00000000 0a000000 02000000 ................
    0x00000030 16000000 00000000 0a000000 0e000000 ................
    0x00000040 1a000000 00000000 0a000000 03000000 ................
               ----------------- -------- --------
                reloc location     type   symtab index

  Hex dump of section '.debug_info':
    0x00000000 7b000000 04000000 00000801 00000000 {...............
    0x00000010 0c000000 00000000 00000000 00000000 ................
    0x00000020 00000000 00001000 00000200 00000000 ................

Based on "type", the proper value will be extracted from symbol table
and filled in .debug_info so later on .debug_info can be properly
resolved against debug strings.

There are two ways to fix this problem. One is to fix elfutils by adding
BPF support which is desirable. This could take a long time and won't work
with already deployed pahole. For a short term workaround, we can disable
dwarf cross-section relation which specifically avoids debug_info and
symbol table cross relocation. This should help any dwarf-related tool
which has not implement BPF specific relocations yet.

Now .rel.debug_info does not have any relocation for symbol table and
.debug_info itself contains necessary relocation information by itself.
  Hex dump of section '.debug_info':
    0x00000000 7b000000 04000000 00000801 00000000 {...............
    0x00000010 0c003700 00000000 00003e00 00000000 ..7.......>.....
    0x00000020 00000000 00001000 00000200 00000000 ................
  location 0xc has 0, 0x12 has 0x37, 0x1a has 0x3e in place which
  will be used in relocation resolution. Here, the values of 0, 0x37 and 0x3e
  are offset in .debug_str section.
Please note the difference between two above .debug_info dumps.

With the fix, pahole works properly with BPF backend:
  -bash-4.2$ clang -O2 -g -target bpf -c test.c
  -bash-4.2$ pahole test.o
  struct test_t {
          int                        a;                    /*     0     4 */
          int                        b;                    /*     4     4 */

          /* size: 8, cachelines: 1, members: 2 */
          /* last cacheline: 8 bytes */
  };

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325735
2018-02-21 22:59:14 +00:00
Jonas Paulsson 891789c299 [BPF] Return true in enableMultipleCopyHints().
Enable multiple COPY hints to eliminate more COPYs during register allocation.

Note that this is something all targets should do, see
https://reviews.llvm.org/D38128.

Review: Yonghong Song
llvm-svn: 325457
2018-02-18 10:09:54 +00:00
Yonghong Song 920df52a93 bpf: fix a bug in dag2dag optimization for loads from readonly section
The reference '&' is missing in the function parameter. If there are
back-to-back optimizations in terms of dag node list like below:
  t29: i64,ch = load<LD4[bitcast (%struct.test_t* @test.t to i8*)+12](dereferenceable), zext from i32> t3, t43, undef:i64
  t34: i64,ch = load<LD4[bitcast (%struct.test_t* @test.t to i8*)](dereferenceable), zext from i32> t3, t41, undef:i64
The bug will trigger a segfault for the added test case remove_truncate_5.ll:
  LLVMSymbolizer: error reading file: No such file or directory
  #0 0x000000000241c4d9 (llc+0x241c4d9)
  #1 0x000000000241c56a (llc+0x241c56a)
  #2 0x000000000241aa50 (llc+0x241aa50)
  ...
  #22 0x0000000000fd5edf (llc+0xfd5edf)
  #23 0x00007f0fe03bec05 __libc_start_main (/lib64/libc.so.6+0x21c05)
  #24 0x0000000000fd3e69 (llc+0xfd3e69)
  ...
  Segmentation fault

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325267
2018-02-15 17:06:45 +00:00
Yonghong Song f2075aef68 bpf: Improve expanding logic in LowerSELECT_CC
LowerSELECT_CC is not generating optimal Select_Ri pattern at the moment. It
is not guaranteed to place ConstantNode at RHS which would miss matching
Select_Ri.

A new testcase added into the existing select_ri.ll, also there is an
existing case in cmp.ll which would be improved to use Select_Ri after this
patch, it is adjusted accordingly.

Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 324560
2018-02-08 04:37:49 +00:00
Craig Topper 8f324bb1a4 [SelectionDAGISel] Add a debug print before call to Select. Adjust where blank lines are printed during isel process to make things more sensibly grouped.
Previously some targets printed their own message at the start of Select to indicate what they were selecting. For the targets that didn't, it means there was no print of the root node before any custom handling in the target executed. So if the target did something custom and never called SelectNodeCommon, no print would be made. For the targets that did print a message in Select, if they didn't custom handle a node SelectNodeCommon would reprint the root node before walking the isel table.

It seems better to just print the message before the call to Select so all targets behave the same. And then remove the root node printing from SelectNodeCommon and just leave a message that says we're starting the table search.

There were also some oddities in blank line behavior. Usually due to a \n after a call to SelectionDAGNode::dump which already inserted a new line.

llvm-svn: 323551
2018-01-26 19:34:20 +00:00
Yonghong Song 035dd256d5 [BPF] Mark pseudo insn patterns as isCodeGenOnly
These pseudos are not supposed to be visible to user.

This patch reduced the auto-generated instruction matcher. For example,
the following words are removed from keyword list of LLVM BPF assembler.

-  MCK__35_, // '#'
-  MCK__COLON_, // ':'
-  MCK__63_, // '?'
-  MCK_ADJCALLSTACKDOWN, // 'ADJCALLSTACKDOWN'
-  MCK_ADJCALLSTACKUP, // 'ADJCALLSTACKUP'
-  MCK_PSEUDO, // 'PSEUDO'
-  MCK_Select, // 'Select'

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 322535
2018-01-16 07:27:20 +00:00
Yonghong Song b42c7c7863 [BPF] Teach DAG2DAG AND elimination about load intrinsics
As commented on the existing code:

  // The Reg operand should be a virtual register, which is defined
  // outside the current basic block. DAG combiner has done a pretty
  // good job in removing truncating inside a single basic block.

However, when the Reg operand comes from bpf_load_[byte | half | word]
intrinsics, the generic optimizer doesn't understand their results are
zero extended, so these single basic block elimination opportunities were
missed.

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 322534
2018-01-16 07:27:19 +00:00
Alex Bradbury b22f751fa7 Thread MCSubtargetInfo through Target::createMCAsmBackend
Currently it's not possible to access MCSubtargetInfo from a TgtMCAsmBackend. 
D20830 threaded an MCSubtargetInfo reference through 
MCAsmBackend::relaxInstruction, but this isn't the only function that would 
benefit from access. This patch removes the Triple and CPUString arguments 
from createMCAsmBackend and replaces them with MCSubtargetInfo.

This patch just changes the interface without making any intentional 
functional changes. Once in, several cleanups are possible:
* Get rid of the awkward MCSubtargetInfo handling in ARMAsmBackend
* Support 16-bit instructions when valid in MipsAsmBackend::writeNopData
* Get rid of the CPU string parsing in X86AsmBackend and just use a SubtargetFeature for HasNopl
* Emit 16-bit nops in RISCVAsmBackend::writeNopData if the compressed instruction set extension is enabled (see D41221)

This change initially exposed PR35686, which has since been resolved in r321026.

Differential Revision: https://reviews.llvm.org/D41349

llvm-svn: 321692
2018-01-03 08:53:05 +00:00
Yonghong Song 25bf825961 bpf: add support for objdump -print-imm-hex
Add support for 'objdump -print-imm-hex' for imm64, operand imm
and branch target. If user programs encode immediate values
as hex numbers, such an option will make it easy to correlate
asm insns with source code. This option also makes it easy
to correlate imm values with insn encoding.

There is one changed behavior in this patch. In old way, we
print the 64bit imm as u64:
  O << (uint64_t)Op.getImm();
and the new way is:
  O << formatImm(Op.getImm());

The formatImm is defined in llvm/MC/MCInstPrinter.h as
  format_object<int64_t> formatImm(int64_t Value)

So the new way to print 64bit imm is i64 type.
If a 64bit value has the highest bit set, the old way
will print the value as a positive value and the
new way will print as a negative value. The new way
is consistent with x86_64.
For the code (see the test program):
 ...
 if (a == 0xABCDABCDabcdabcdULL)
 ...
x86_64 objdump, with and without -print-imm-hex, looks like:
 48 b8 cd ab cd ab cd ab cd ab   movabsq $-6067004223159161907, %rax
 48 b8 cd ab cd ab cd ab cd ab   movabsq $-0x5432543254325433, %rax

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 321215
2017-12-20 19:39:58 +00:00
Matthias Braun f1caa2833f MachineFunction: Return reference from getFunction(); NFC
The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
2017-12-15 22:22:58 +00:00
Francis Visoiu Mistrih a8a83d150f [CodeGen] Use MachineOperand::print in the MIRPrinter for MO_Register.
Work towards the unification of MIR and debug output by refactoring the
interfaces.

For MachineOperand::print, keep a simple version that can be easily called
from `dump()`, and a more complex one which will be called from both the
MIRPrinter and MachineInstr::print.

Add extra checks inside MachineOperand for detached operands (operands
with getParent() == nullptr).

https://reviews.llvm.org/D40836

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/kill: ([^ ]+) ([^ ]+)<def> ([^ ]+)/kill: \1 def \2 \3/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/kill: ([^ ]+) ([^ ]+) ([^ ]+)<def>/kill: \1 \2 def \3/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/kill: def ([^ ]+) ([^ ]+) ([^ ]+)<def>/kill: def \1 \2 def \3/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/<def>//g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<kill>/killed \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-use,kill>/implicit killed \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<dead>/dead \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<def[ ]*,[ ]*dead>/dead \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-def[ ]*,[ ]*dead>/implicit-def dead \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-def>/implicit-def \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-use>/implicit \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<internal>/internal \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<undef>/undef \1/g'

llvm-svn: 320022
2017-12-07 10:40:31 +00:00
Francis Visoiu Mistrih 25528d6de7 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
2017-12-04 17:18:51 +00:00
Francis Visoiu Mistrih c71cced0aa [CodeGen] Always use `printReg` to print registers in both MIR and debug
output

As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.

Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.

Differential Revision: https://reviews.llvm.org/D40421

llvm-svn: 319445
2017-11-30 16:12:24 +00:00
Francis Visoiu Mistrih 93ef145862 [CodeGen] Print "%vreg0" as "%0" in both MIR and debug output
As part of the unification of the debug format and the MIR format, avoid
printing "vreg" for virtual registers (which is one of the current MIR
possibilities).

Basically:

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/%vreg([0-9]+)/%\1/g"
* grep -nr '%vreg' . and fix if needed
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/ vreg([0-9]+)/ %\1/g"
* grep -nr 'vreg[0-9]\+' . and fix if needed

Differential Revision: https://reviews.llvm.org/D40420

llvm-svn: 319427
2017-11-30 12:12:19 +00:00
Alexei Starovoitov 9bd566f8c8 [bpf] remove unused variable
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 318615
2017-11-19 02:41:53 +00:00
Alexei Starovoitov 9a67245d88 [bpf] allow direct and indirect calls
kernel verifier is becoming smarter and soon will support
direct and indirect function calls.
Remove obsolete error from BPF backend.
Make call to use PCRel_4 fixup.
'bpf to bpf' calls are distinguished from 'bpf to kernel' calls
by insn->src_reg == BPF_PSEUDO_CALL == 1 which is used as relocation
indicator similar to ld_imm64->src_reg == BPF_PSEUDO_MAP_FD == 1
The actual 'call' instruction remains the same for both
'bpf to kernel' and 'bpf to bpf' calls.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 318614
2017-11-19 01:35:00 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Yonghong Song ce96738dee bpf: print backward branch target properly
Currently, it prints the backward branch offset as unsigned value
like below:
       7:       7d 34 0b 00 00 00 00 00         if r4 s>= r3 goto 11 <LBB0_3>
       8:       b7 00 00 00 00 00 00 00         r0 = 0
LBB0_2:
       9:       07 00 00 00 01 00 00 00         r0 += 1
      ......
      17:       bf 31 00 00 00 00 00 00         r1 = r3
      18:       6d 32 f6 ff 00 00 00 00         if r2 s> r3 goto 65526 <LBB0_3+0x7FFB0>

The correct print insn 18 should be:
      18:       6d 32 f6 ff 00 00 00 00         if r2 s> r3 goto -10 <LBB0_2>

To provide better clarity and be consistent with kernel verifier output,
the insn 7 output is changed to the following with "+" added to
non-negative branch offset:
       7:       7d 34 0b 00 00 00 00 00         if r4 s>= r3 goto +11 <LBB0_3>

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 318442
2017-11-16 19:15:36 +00:00
Yonghong Song 4c3ce59e61 bpf: enable llvm-objdump to print out symbolized jmp target
Add hook in BPF backend so that llvm-objdump can print out
the jmp target with label names, e.g.,
  ...
  if r1 != 2 goto 6 <LBB0_2>
  ...
  goto 7 <LBB0_4>
  ...
 LBB0_2:
  ...
 LBB0_4:
  ...

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 318358
2017-11-16 00:52:30 +00:00
Daniel Sanders 725584e26d Add backend name to Target to enable runtime info to be fed back into TableGen
Summary:
Make it possible to feed runtime information back to tablegen to enable
profile-guided tablegen-eration, detection of untested tablegen definitions, etc.

Being a cross-compiler by nature, LLVM will potentially collect data for multiple
architectures (e.g. when running 'ninja check'). We therefore need a way for
TableGen to figure out what data applies to the backend it is generating at the
time. This patch achieves that by including the name of the 'def X : Target ...'
for the backend in the TargetRegistry.

Reviewers: qcolombet

Reviewed By: qcolombet

Subscribers: jholewinski, arsenm, jyknight, aditya_nandakumar, sdardis, nemanjai, ab, nhaehnle, t.p.northover, javed.absar, qcolombet, llvm-commits, fedor.sergeev

Differential Revision: https://reviews.llvm.org/D39742

llvm-svn: 318352
2017-11-15 23:55:44 +00:00
David Blaikie 3f833edc7c Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layering
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.

llvm-svn: 317647
2017-11-08 01:01:31 +00:00
David Blaikie 1be62f0327 Move TargetFrameLowering.h to CodeGen where it's implemented
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.

This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.

llvm-svn: 317379
2017-11-03 22:32:11 +00:00
Yonghong Song 9af998e86e bpf: fix an uninitialized variable issue
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 316519
2017-10-24 21:36:33 +00:00
Yonghong Song ee68d8e41f bpf: fix a bug in trunc-op optimization
Previous implementation for per-function scope
is incorrect and too conservative.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 316481
2017-10-24 18:21:10 +00:00
Yonghong Song 0f836d5dc5 bpf: fix a bug in bpf-isel trunc-op optimization
In BPF backend, we try to optimize away redundant
trunc operations so that kernel verifier rewrite
remains valid. Previous implementation only works
for a single function.

This patch fixed the issue for multiple functions.
It clears internal map data structure before
performing optimization for each function.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 316469
2017-10-24 17:29:03 +00:00
Yonghong Song 6621cf67cf bpf: fix bug on silently truncating 64-bit immediate
We came across an llvm bug when compiling some testcases that 64-bit
immediates are silently truncated into 32-bit and then packed into
BPF_JMP | BPF_K encoding.  This caused comparison with wrong value.

This bug looks to be introduced by r308080.  The Select_Ri pattern is
supposed to be lowered into J*_Ri while the latter only support 32-bit
immediate encoding, therefore Select_Ri should have similar immediate
predicate check as what J*_Ri are doing.

Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 315889
2017-10-16 04:14:53 +00:00
Matthias Braun bb8507e63c Revert "TargetMachine: Merge TargetMachine and LLVMTargetMachine"
Reverting to investigate layering effects of MCJIT not linking
libCodeGen but using TargetMachine::getNameWithPrefix() breaking the
lldb bots.

This reverts commit r315633.

llvm-svn: 315637
2017-10-12 22:57:28 +00:00
Matthias Braun 3a9c114b24 TargetMachine: Merge TargetMachine and LLVMTargetMachine
Merge LLVMTargetMachine into TargetMachine.

- There is no in-tree target anymore that just implements TargetMachine
  but not LLVMTargetMachine.
- It should still be possible to stub out all the various functions in
  case a target does not want to use lib/CodeGen
- This simplifies the code and avoids methods ending up in the wrong
  interface.

Differential Revision: https://reviews.llvm.org/D38489

llvm-svn: 315633
2017-10-12 22:28:54 +00:00
Lang Hames 2241ffa43c [MC] Have MCObjectStreamer take its MCAsmBackend argument via unique_ptr.
MCObjectStreamer owns its MCCodeEmitter -- this fixes the types to reflect that,
and allows us to remove the last instance of MCObjectStreamer's weird "holding
ownership via someone else's reference" trick.

llvm-svn: 315531
2017-10-11 23:34:47 +00:00
Oliver Stannard 4191b9eaea [Asm] Add debug tracing in table-generated assembly matcher
This adds debug tracing to the table-generated assembly instruction matcher,
enabled by the -debug-only=asm-matcher option.

The changes in the target AsmParsers are to add an MCInstrInfo reference under
a consistent name, so that we can use it from table-generated code. This was
already being used this way for targets that use deprecation warnings, but 5
targets did not have it, and Hexagon had it under a different name to the other
backends.

llvm-svn: 315445
2017-10-11 09:17:43 +00:00
Lang Hames 02d330548d [MC] Have MCObjectStreamer take its MCAsmBackend argument via unique_ptr.
MCObjectStreamer owns its MCAsmBackend -- this fixes the types to reflect that,
and allows us to remove another instance of MCObjectStreamer's weird "holding
ownership via someone else's reference" trick.

llvm-svn: 315410
2017-10-11 01:57:21 +00:00
Lang Hames 60fbc7cc38 [MC] Thread unique_ptr<MCObjectWriter> through the create.*ObjectWriter
functions.

This makes the ownership of the resulting MCObjectWriter clear, and allows us
to remove one instance of MCObjectStreamer's bizarre "holding ownership via
someone else's reference" trick.

llvm-svn: 315327
2017-10-10 16:28:07 +00:00
Lang Hames dcb312bdb9 [MC] Plumb unique_ptr<MCELFObjectTargetWriter> through createELFObjectWriter to
ELFObjectWriter's constructor.

Fixes the same ownership issue for ELF that r315245 did for MachO:
ELFObjectWriter takes ownership of its MCELFObjectTargetWriter, so we want to
pass this through to the constructor via a unique_ptr, rather than a raw ptr.

llvm-svn: 315254
2017-10-09 23:53:15 +00:00
Yonghong Song 09b01b3555 bpf: fix an insn encoding issue for neg insn
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 314911
2017-10-04 16:11:52 +00:00
Yonghong Song ef29a84d48 bpf: fix a bug for disassembling ld_pseudo inst
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 314469
2017-09-28 22:47:34 +00:00
Yonghong Song e9165f8720 bpf: add new insns for bswap_to_le and negation
This patch adds new insn, "reg = be16/be32/be64 reg",
for bswap to little endian for big-endian target (bpfeb).
It also adds new insn for negation "reg = -reg".

Currently, for source code, e.g.,
  b = -a
LLVM still prefers to generate:
  b = 0 - a
But "reg = -reg" format can be used in assembly code.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 314376
2017-09-28 02:46:11 +00:00
Yonghong Song d2e0d1fa11 bpf: initial 32-bit ALU encoding support in assembler
This patch adds instruction patterns for operations in BPF_ALU. After this,
assembler could recognize some 32-bit ALU statement. For example, those listed
int the unit test file.

Separate MOV patterns are unnecessary as MOV is ALU operation that could reuse
ALU encoding infrastructure, this patch removed those redundant patterns.

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 313961
2017-09-22 04:36:36 +00:00
Yonghong Song 3c63b101de bpf: add 32bit register set
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 313960
2017-09-22 04:36:35 +00:00
Yonghong Song d03fef970b bpf: refactor inst patterns with better inheritance
Arithmetic and jump instructions, load and store instructions are sharing
the same 8-bit code field encoding,

A better instruction pattern implemention could be the following inheritance
relationships, and each layer only encoding those fields which start to
diverse from that layer. This avoids some redundant code.

  InstBPF -> TYPE_ALU_JMP -> ALU/JMP
  InstBPF -> TYPE_LD_ST -> Load/Store

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 313959
2017-09-22 04:36:34 +00:00
Yonghong Song 3bf1a8d04e bpf: refactor inst patterns with more mnemonics
Currently, eBPF backend is using some constant directly in instruction patterns,
This patch replace them with mnemonics and removed some unnecessary temparary
variables.

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 313958
2017-09-22 04:36:32 +00:00
Yonghong Song 9ef85f0677 bpf: add inline-asm support
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 313593
2017-09-18 23:29:36 +00:00
Yonghong Song 06ff655e59 bpf: Add BPF AsmParser support in LLVM
Reviewed-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 313055
2017-09-12 17:55:23 +00:00
Yonghong Song be9c00347f bpf: add " ll" in the LD_IMM64 asmstring
This partially revert previous fix in commit f5858045aa0b
("bpf: proper print imm64 expression in inst printer").

In that commit, the original suffix "ll" is removed from
LD_IMM64 asmstring. In the customer print method, the "ll"
suffix is printed if the rhs is an immediate. For example,
"r2 = 5ll" => "r2 = 5ll", and "r3 = varll" => "r3 = var".

This has an issue though for assembler. Since assembler
relies on asmstring to do pattern matching, it will not
be able to distiguish between "mov r2, 5" and
"ld_imm64 r2, 5" since both asmstring is "r2 = 5".
In such cases, the assembler uses 64bit load for all
"r = <val>" asm insts.

This patch adds back " ll" suffix for ld_imm64 with one
additional space for "#reg = #global_var" case.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 312978
2017-09-11 23:43:35 +00:00
Yonghong Song 093420f929 bpf: proper print imm64 expression in inst printer
Fixed an issue in printImm64Operand where if the value is
an expression, print out the expression properly. Currently,
it will print
  r1 = <MCOperand Expr:(tx_port)>ll
With the patch, the printout will be
  r1 = tx_port

Suggested-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 312833
2017-09-08 23:32:38 +00:00
Yonghong Song dc1dbf6ef3 bpf: add variants of -mcpu=# and support for additional jmp insns
-mcpu=# will support:
  . generic: the default insn set
  . v1: insn set version 1, the same as generic
  . v2: insn set version 2, version 1 + additional jmp insns
  . probe: the compiler will probe the underlying kernel to
           decide proper version of insn set.

We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native
as the underlying hardware architecture regardless of -march value.

Currently, only x86_64 supports -mcpu=probe. Other architecture will
silently revert to "generic".

Also added -mcpu=help to print available cpu parameters.
llvm will print out the information only if there are at least one
cpu and at least one feature. Add an unused dummy feature to
enable the printout.

Examples for usage:
$ llc -march=bpf -mcpu=v1 -filetype=asm t.ll
$ llc -march=bpf -mcpu=v2 -filetype=asm t.ll
$ llc -march=bpf -mcpu=generic -filetype=asm t.ll
$ llc -march=bpf -mcpu=probe -filetype=asm t.ll
$ llc -march=bpf -mcpu=v3 -filetype=asm t.ll
'v3' is not a recognized processor for this target (ignoring processor)
...
$ llc -march=bpf -mcpu=help -filetype=asm t.ll
Available CPUs for this target:

  generic - Select the generic processor.
  probe   - Select the probe processor.
  v1      - Select the v1 processor.
  v2      - Select the v2 processor.

Available features for this target:

  dummy - unused feature.

Use +feature to enable a feature, or -feature to disable it.
For example, llc -mcpu=mycpu -mattr=+feature1,-feature2
...

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 311522
2017-08-23 04:25:57 +00:00
Alex Bradbury 080f6976c0 Use report_fatal_error for unsupported calling conventions
The calling convention can be specified by the user in IR. Failing to support 
a particular calling convention isn't a programming error, and so relying on 
llvm_unreachable to catch and report an unsupported calling convention is not 
appropriate.

Differential Revision: https://reviews.llvm.org/D36830

llvm-svn: 311435
2017-08-22 09:11:41 +00:00
Rafael Espindola 79e238afee Delete Default and JITDefault code models
IMHO it is an antipattern to have a enum value that is Default.

At any given piece of code it is not clear if we have to handle
Default or if has already been mapped to a concrete value. In this
case in particular, only the target can do the mapping and it is nice
to make sure it is always done.

This deletes the two default enum values of CodeModel and uses an
explicit Optional<CodeModel> when it is possible that it is
unspecified.

llvm-svn: 309911
2017-08-03 02:16:21 +00:00
Yonghong Song fbfae984b4 bpf: fix a compilation bug due to unused variable for release build
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 308083
2017-07-15 06:08:08 +00:00
Yonghong Song 9276ef05c8 bpf: generate better lowering code for certain select/setcc instructions
Currently, for code like below,
===
  inner_map = bpf_map_lookup_elem(outer_map, &port_key);
  if (!inner_map) {
    inner_map = &fallback_map;
  }
===
the compiler generates (pseudo) code like the below:
===
  I1: r1 = bpf_map_lookup_elem(outer_map, &port_key);
  I2: r2 = 0
  I3: if (r1 == r2)
  I4:   r6 = &fallback_map
  I5: ...
===

During kernel verification process, After I1, r1 holds a state
map_ptr_or_null. If I3 condition is not taken
(path [I1, I2, I3, I5]), supposedly r1 should become map_ptr.
Unfortunately, kernel does not recognize this pattern
and r1 remains map_ptr_or_null at insn I5. This will cause
verificaiton failure later on.

Kernel, however, is able to recognize pattern "if (r1 == 0)"
properly and give a map_ptr state to r1 in the above case.

LLVM here generates suboptimal code which causes kernel verification
failure. This patch fixes the issue by changing BPF insn pattern
matching and lowering to generate proper codes if the righthand
parameter of the above condition is a constant. A test case
is also added.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 308080
2017-07-15 05:41:42 +00:00
Rafael Espindola 1beb702ba2 Fully fix the movw/movt addend.
The issue is not if the value is pcrel. It is whether we have a
relocation or not.

If we have a relocation, the static linker will select the upper
bits. If we don't have a relocation, we have to do it.

llvm-svn: 307730
2017-07-11 23:18:25 +00:00
Yonghong Song 5fbe01b12d bpf: remove unnecessary truncate operation
For networking-type bpf program, it often needs to access
packet data. A context data structure is provided to the bpf
programs with two fields:
        u32 data;
        u32 data_end;
User can access these two fields with ctx->data and ctx->data_end.
During program verification process, the kernel verifier modifies
the bpf program with loading of actual pointer value from kernel
data structure.
    r = ctx->data      ===> r = actual data start ptr
    r = ctx->data_end  ===> r = actual data end ptr

A typical program accessing ctx->data like
    char *data_ptr = (char *)(long)ctx->data
will result in a 32-bit load followed by a zero extension.
Such an operation is combined into a single LDW in DAG combiner
as bpf LDW does zero extension automatically.

In cases like the below (which can be a result of global value numbering
and partial redundancy elimination before insn selection):
B1:
   u32 a = load-32-bit &ctx->data
   u64 pa = zext a
   ...
B2:
   u32 b = load-32-bit &ctx->data
   u64 pb = zext b
   ...
B3:
   u32 m = PHI(a, b)
   u64 pm = zext m

In B3, "pm = zext m" cannot be removed, which although is legal
from compiler perspective, will generate incorrect code after
kernel verification.

This patch recognizes this pattern and traces through PHI node
to see whether the operand of "zext m" is defined with LDWs or not.
If it is, the "zext m" itself can be removed.

The patch also recognizes the pattern where the load and use of
the load value not in the same basic block, where truncate operation
may be removed as well.

The patch handles 1-byte, 2-byte and 4-byte truncation.

Two test cases are added to verify the transformation happens properly
for the above code pattern.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 306685
2017-06-29 15:18:54 +00:00
Rafael Espindola f351292141 Remove redundant argument.
llvm-svn: 306189
2017-06-24 00:26:57 +00:00
Rafael Espindola 801b42de31 ARM: move some logic from processFixupValue to applyFixup.
processFixupValue is called on every relaxation iteration. applyFixup
is only called once at the very end. applyFixup is then the correct
place to do last minute changes and value checks.

While here, do proper range checks again for fixup_arm_thumb_bl. We
used to do it, but dropped because of thumb2. We now do it again, but
use the thumb2 range.

llvm-svn: 306177
2017-06-23 22:52:36 +00:00
Rafael Espindola 88d9e37ec8 Use a MutableArrayRef. NFC.
llvm-svn: 305968
2017-06-21 23:06:53 +00:00
Yonghong Song a63178f756 bpf: fix a strict-aliasing issue
Davide Italiano reported the following issue if llvm
is compiled with gcc -Wstrict-aliasing -Werror:
.....
lib/Target/BPF/CMakeFiles/LLVMBPFCodeGen.dir/BPFISelDAGToDAG.cpp.o
../lib/Target/BPF/BPFISelDAGToDAG.cpp: In member function ‘virtual
void {anonymous}::BPFDAGToDAGISel::PreprocessISelDAG()’:
../lib/Target/BPF/BPFISelDAGToDAG.cpp:264:26: warning: dereferencing
type-punned pointer will break strict-aliasing rules
[-Wstrict-aliasing]
       val = *(uint16_t *)new_val;
.....

The error is caused by my previous commit (revision 305560).

This patch fixed the issue by introducing an union to avoid
type casting.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 305608
2017-06-16 23:28:04 +00:00
Yonghong Song ac2e25026f bpf: avoid load from read-only sections
If users tried to have a structure decl/init code like below
   struct test_t t = { .memeber1 = 45 };
It is very likely that compiler will generate a readonly section
to hold up the init values for variable t. Later load of t members,
e.g., t.member1 will result in a read from readonly section.

BPF program cannot handle relocation. This will force users to
write:
  struct test_t t = {};
  t.member1 = 45;
This is just inconvenient and unintuitive.

This patch addresses this issue by implementing BPF PreprocessISelDAG.
For any load from a global constant structure or an global array of
constant struct, it attempts to
translate it into a constant directly. The traversal of the
constant struct and other constant data structures are similar
to where the assembler emits read-only sections.

Four different unit test cases are also added to cover
different scenarios.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 305560
2017-06-16 15:41:16 +00:00
Yonghong Song 5c65439617 bpf: set missing types in insn tablegen file
o This is discovered during my study of 32-bit subregister
  support.
o This is no impact on current functionality since we
  only support 64-bit registers.
o Searching the web, looks like the issue has been discovered
  before, so fix it now.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 305559
2017-06-16 15:30:55 +00:00
Yonghong Song 7e9d2cb553 bpf: clang-format on BPFAsmPrinter.cpp
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 305301
2017-06-13 16:17:20 +00:00
Zachary Turner 264b5d9e88 Move Object format code to lib/BinaryFormat.
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.

Differential Revision: https://reviews.llvm.org/D33843

llvm-svn: 304864
2017-06-07 03:48:56 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Craig Topper fa5dc09292 [BPF] Correct the file name of the -gen-asm-matcher output file to not start with X86.
llvm-svn: 304324
2017-05-31 19:01:05 +00:00
Matthias Braun 5e394c3d6f TargetPassConfig: Keep a reference to an LLVMTargetMachine; NFC
TargetPassConfig is not useful for targets that do not use the CodeGen
library, so we may just as well store a pointer to an
LLVMTargetMachine instead of just to a TargetMachine.

While at it, also change the constructor to take a reference instead of a
pointer as the TM must not be nullptr.

llvm-svn: 304247
2017-05-30 21:36:41 +00:00
Alexei Starovoitov 3c585d3a8f [bpf] disallow global_addr+off folding
Wrong assembly code is generated for a simple program with
clang. If clang only produces IR and llc is used
for IR lowering and optimization, correct assembly
code is generated.

The main reason is that clang feeds default Reloc::Static
to llvm and llc feeds no RelocMode to llvm, where
for llc case, BPF backend picks up Reloc::PIC_ mode.
This leads different IR lowering behavior and clang
permits global_addr+off folding while llc doesn't.

This patch introduces isOffsetFoldingLegal function into
BPF backend and the function always return false.
This will make clang and llc behave the same for
the lowering.

Bug https://bugs.llvm.org//show_bug.cgi?id=33183
has more detailed explanation.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 304043
2017-05-26 22:32:41 +00:00
Serge Pavlov d526b13e61 Add extra operand to CALLSEQ_START to keep frame part set up previously
Using arguments with attribute inalloca creates problems for verification
of machine representation. This attribute instructs the backend that the
argument is prepared in stack prior to  CALLSEQ_START..CALLSEQ_END
sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size
stored in CALLSEQ_START in this case does not count the size of this
argument. However CALLSEQ_END still keeps total frame size, as caller can
be responsible for cleanup of entire frame. So CALLSEQ_START and
CALLSEQ_END keep different frame size and the difference is treated by
MachineVerifier as stack error. Currently there is no way to distinguish
this case from actual errors.

This patch adds additional argument to CALLSEQ_START and its
target-specific counterparts to keep size of stack that is set up prior to
the call frame sequence. This argument allows MachineVerifier to calculate
actual frame size associated with frame setup instruction and correctly
process the case of inalloca arguments.

The changes made by the patch are:
- Frame setup instructions get the second mandatory argument. It
  affects all targets that use frame pseudo instructions and touched many
  files although the changes are uniform.
- Access to frame properties are implemented using special instructions
  rather than calls getOperand(N).getImm(). For X86 and ARM such
  replacement was made previously.
- Changes that reflect appearance of additional argument of frame setup
  instruction. These involve proper instruction initialization and
  methods that access instruction arguments.
- MachineVerifier retrieves frame size using method, which reports sum of
  frame parts initialized inside frame instruction pair and outside it.

The patch implements approach proposed by Quentin Colombet in
https://bugs.llvm.org/show_bug.cgi?id=27481#c1.
It fixes 9 tests failed with machine verifier enabled and listed
in PR27481.

Differential Revision: https://reviews.llvm.org/D32394

llvm-svn: 302527
2017-05-09 13:35:13 +00:00
Alexei Starovoitov 7bab73b1f8 [bpf] fix a bug which causes incorrect big endian reloc fixup
o Add bpfeb support in BPF dwarfdump unit test case

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@fb.com>
llvm-svn: 302265
2017-05-05 18:05:00 +00:00
Alexei Starovoitov f7bd5ebd3b [bpf] add bigendian support to disassembler
. swap 4-bit register encoding, 16-bit offset and 32-bit imm to support big endian archs
. add a test

Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 301653
2017-04-28 16:51:01 +00:00
Konstantin Zhuravlyov dc77b2e960 Distinguish between code pointer size and DataLayout::getPointerSize() in DWARF info generation
llvm-svn: 300463
2017-04-17 17:41:25 +00:00
Alexei Starovoitov 56db145164 [bpf] Fix memory offset check for loads and stores
If the offset cannot fit into the instruction, an addition to the
pointer is emitted before the actual access. However, BPF offsets are
16-bit but LLVM considers them to be, for the matter of this check,
to be 32-bit long.

This causes the following program:

int bpf_prog1(void *ign)
{

volatile unsigned long t = 0x8983984739ull;
return *(unsigned long *)((0xffffffff8fff0002ull) + t);

}

To generate the following (wrong) code:

0: 18 01 00 00 39 47 98 83 00 00 00 00 89 00 00 00

r1 = 590618314553ll

2: 7b 1a f8 ff 00 00 00 00 *(u64 *)(r10 - 8) = r1
3: 79 a1 f8 ff 00 00 00 00 r1 = *(u64 *)(r10 - 8)
4: 79 10 02 00 00 00 00 00 r0 = *(u64 *)(r1 + 2)
5: 95 00 00 00 00 00 00 00 exit

Fix it by changing the offset check to 16-bit.

Patch by Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Differential Revision: https://reviews.llvm.org/D32055

llvm-svn: 300269
2017-04-13 22:24:13 +00:00
Alex Bradbury 866113c2ea Add MCContext argument to MCAsmBackend::applyFixup for error reporting
A number of backends (AArch64, MIPS, ARM) have been using
MCContext::reportError to report issues such as out-of-range fixup values in
their TgtAsmBackend. This is great, but because MCContext couldn't easily be
threaded through to the adjustFixupValue helper function from its usual
callsite (applyFixup), these backends ended up adding an MCContext* argument
and adding another call to applyFixup to processFixupValue. Adding an
MCContext parameter to applyFixup makes this unnecessary, and even better -
applyFixup can take a reference to MCContext rather than a potentially null
pointer.

Differential Revision: https://reviews.llvm.org/D30264

llvm-svn: 299529
2017-04-05 10:16:14 +00:00
Matthias Braun 8c209aa877 Cleanup dump() functions.
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html

For reference:
- Public headers should just declare the dump() method but not use
  LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
  #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  LLVM_DUMP_METHOD void MyClass::dump() {
    // print stuff to dbgs()...
  }
  #endif

llvm-svn: 293359
2017-01-28 02:02:38 +00:00
Alexei Starovoitov efefbc4a19 [bpf] fix stack-use-after-scope
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 292258
2017-01-17 21:14:00 +00:00
Alexei Starovoitov e4975487f5 [bpf] error when unknown bpf helper is called
Emit error when BPF backend sees a call to a global function or to an external symbol.
The kernel verifier only allows calls to predefined helpers from bpf.h
which are defined in 'enum bpf_func_id'. Such calls in assembler must
look like 'call [1-9]+' where number matches bpf_func_id.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 292204
2017-01-17 07:26:17 +00:00
Alexei Starovoitov 05de2e4818 [bpf] error when BPF stack size exceeds 512 bytes
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 292180
2017-01-17 01:05:17 +00:00
Eugene Zelenko 4282c404f9 [BPF] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 291297
2017-01-06 23:06:25 +00:00
Alexei Starovoitov 7ab125dbf3 [bpf] fix dwarf elf relocs and line numbers
- teach RelocVisitor to recognize bpf relocations
- fix AsmInfo->PointerSize to make sure dwarf is emitted correctly
- add a test for the above

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 287521
2016-11-21 06:21:23 +00:00
Alexei Starovoitov e6ddac0def [bpf] add BPF disassembler
add BPF disassembler, so tools like llvm-objdump can be used:
$ llvm-objdump -d -no-show-raw-insn ./sockex1_kern.o

./sockex1_kern.o:	file format ELF64-BPF

Disassembly of section socket1:
bpf_prog1:
       0:	r6 = r1
       8:	r0 = *(u8 *)skb[23]
      10:	*(u32 *)(r10 - 4) = r0
      18:	r1 = *(u32 *)(r6 + 4)
      20:	if r1 != 4 goto 8
      28:	r2 = r10
      30:	r2 += -4

ld_imm64 (the only 16-byte insn) and special ld_abs/ld_ind instructions
had to be treated in a special way. The decoders for the rest of the insns
are automatically generated.

Add tests to cover new functionality.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 287477
2016-11-20 02:25:00 +00:00
Daniel Sanders c95590bc45 Try again to fix unused variable warning on lld-x86_64-darwin13 after r287439.
The previous attempt didn't work. I assume LLVM_ATTRIBUTE_UNUSED isn't
available on that machine.

llvm-svn: 287442
2016-11-19 14:47:41 +00:00
Daniel Sanders c6d1986a84 Try to fix unused variable warning on lld-x86_64-darwin13 after r287439.
Whether the variable is used or not depends on NDEBUG.

llvm-svn: 287440
2016-11-19 13:50:32 +00:00
Daniel Sanders 72db2a390a Check that emitted instructions meet their predicates on all targets except ARM, Mips, and X86.
Summary:
* ARM is omitted from this patch because this check appears to expose bugs in this target.
* Mips is omitted from this patch because this check either detects bugs or deliberate
  emission of instructions that don't satisfy their predicates. One deliberate
  use is the SYNC instruction where the version with an operand is correctly
  defined as requiring MIPS32 while the version without an operand is defined
  as an alias of 'SYNC 0' and requires MIPS2.
* X86 is omitted from this patch because it doesn't use the tablegen-erated
  MCCodeEmitter infrastructure.

Patches for ARM and Mips will follow.

Depends on D25617

Reviewers: tstellarAMD, jmolloy

Subscribers: wdng, jmolloy, aemerson, rengolin, arsenm, jyknight, nemanjai, nhaehnle, tstellarAMD, llvm-commits

Differential Revision: https://reviews.llvm.org/D25618

llvm-svn: 287439
2016-11-19 13:05:44 +00:00
Alexei Starovoitov 8f9f8210c1 convert bpf assembler to look like kernel verifier output
since bpf instruction set was introduced people learned to
read and understand kernel verifier output whereas llvm asm
output stayed obscure and unknown. Convert llvm to emit
assembler text similar to kernel to avoid this discrepancy

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 287300
2016-11-18 02:32:35 +00:00
Mehdi Amini f42454b94b Move the global variables representing each Target behind accessor function
This avoids "static initialization order fiasco"

Differential Revision: https://reviews.llvm.org/D25412

llvm-svn: 283702
2016-10-09 23:00:34 +00:00
Mehdi Amini 117296c0a0 Use StringRef in Pass/PassManager APIs (NFC)
llvm-svn: 283004
2016-10-01 02:56:57 +00:00
Matt Arsenault 1b9fc8ed65 Finish renaming remaining analyzeBranch functions
llvm-svn: 281535
2016-09-14 20:43:16 +00:00
Matt Arsenault e8e0f5cac6 Make analyzeBranch family of instruction names consistent
analyzeBranch was renamed to use lowercase first, rename
the related set to match.

llvm-svn: 281506
2016-09-14 17:24:15 +00:00
Matt Arsenault a2b036e88b AArch64: Use TTI branch functions in branch relaxation
The main change is to return the code size from
InsertBranch/RemoveBranch.

Patch mostly by Tim Northover

llvm-svn: 281505
2016-09-14 17:23:48 +00:00
Matthias Braun 941a705b7b MachineFunction: Return reference for getFrameInfo(); NFC
getFrameInfo() never returns nullptr so we should use a reference
instead of a pointer.

llvm-svn: 277017
2016-07-28 18:40:00 +00:00
Joel Jones 373d7d30dd MC] Provide an MCTargetOptions to implementors of MCAsmBackendCtorTy, NFC
Some targets, notably AArch64 for ILP32, have different relocation encodings
based upon the ABI. This is an enabling change, so a future patch can use the
ABIName from MCTargetOptions to chose which relocations to use. Tested using
check-llvm.

The corresponding change to clang is in: http://reviews.llvm.org/D16538

Patch by: Joel Jones

Differential Revision: https://reviews.llvm.org/D16213

llvm-svn: 276654
2016-07-25 17:18:28 +00:00
Alexei Starovoitov cfb51f54ba BPF: Use official ELF e_machine value
The same value for EM_BPF is being propagated to glibc,
elfutils, and binutils.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 275633
2016-07-15 22:27:55 +00:00
Jacques Pienaar 71c30a14b7 Rename AnalyzeBranch* to analyzeBranch*.
Summary: NFC. Rename AnalyzeBranch/AnalyzeBranchPredicate to analyzeBranch/analyzeBranchPredicate to follow LLVM coding style and be consistent with TargetInstrInfo's analyzeCompare and analyzeSelect.

Reviewers: tstellarAMD, mcrosier

Subscribers: mcrosier, jholewinski, jfb, arsenm, dschuff, jyknight, dsanders, nemanjai

Differential Revision: https://reviews.llvm.org/D22409

llvm-svn: 275564
2016-07-15 14:41:04 +00:00
Nirav Dave 8603062ee4 Fix branch relaxation in 16-bit mode.
Thread through MCSubtargetInfo to relaxInstruction function allowing relaxation
to generate jumps with 16-bit sized immediates in 16-bit mode.

This fixes PR22097.

Reviewers: dwmw2, tstellarAMD, craig.topper, jyknight

Subscribers: jfb, arsenm, jyknight, llvm-commits, dsanders

Differential Revision: http://reviews.llvm.org/D20830

llvm-svn: 275068
2016-07-11 14:23:53 +00:00
Duncan P. N. Exon Smith e4f5e4f4d1 CodeGen: Use MachineInstr& in TargetLowering, NFC
This is a mechanical change to make TargetLowering API take MachineInstr&
(instead of MachineInstr*), since the argument is expected to be a valid
MachineInstr.  In one case, changed a parameter from MachineInstr* to
MachineBasicBlock::iterator, since it was used as an insertion point.

As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.

llvm-svn: 274287
2016-06-30 22:52:52 +00:00
Rafael Espindola d86e8bb0ed Delete MCCodeGenInfo.
MC doesn't really care about CodeGen stuff, so this was just
complicating target initialization.

llvm-svn: 274258
2016-06-30 18:25:11 +00:00
Reid Kleckner 858239d5f8 Prune some includes from headers and sink some inline functions
MCSymbol.h shouldn't pull in MCAssembler.h, just MCFragment.h.
MCLinkerOptimizationHint.h shouldn't need MCMachObjectWriter.h.  The
rest is fixing the fallout.

llvm-svn: 273507
2016-06-22 23:23:08 +00:00
Rafael Espindola 2b7fef681f Delete more dead code.
Found by gcc 6.

llvm-svn: 273402
2016-06-22 12:44:16 +00:00
Benjamin Kramer bdc4956bac Pass DebugLoc and SDLoc by const ref.
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.

llvm-svn: 272512
2016-06-12 15:39:02 +00:00
Diana Picus f353a5e06d [BPF] Remove exit-on-error from tests (PR27768, PR27769)
The exit-on-error flag is necessary to avoid some assertions/unreachables. We
can get past them by creating a few dummy nodes.

Fixes PR27768, PR27769.

Differential Revision: http://reviews.llvm.org/D20726

llvm-svn: 271200
2016-05-30 08:28:34 +00:00
Diana Picus 20a8d8e97e [BPF] Remove exit-on-error flag in test (PR27767)
The exit-on-error flag is needed to avoid an assert where
llvm::SelectionDAGISel::LowerArguments doesn't create enough arguments. Fill up
with zeroes to reach the right number of args.

Fixes PR27767.

Differential Revision: http://reviews.llvm.org/D20571

llvm-svn: 270855
2016-05-26 15:23:50 +00:00
Diana Picus b2da61196e [BPF] Remove exit-on-error flag in test (PR27766)
The exit-on-error flag on the many_args1.ll test is needed to avoid an
unreachable in BPFTargetLowering::LowerCall. We can also avoid it by ignoring
any superfluous arguments to the call (i.e. any arguments after the first 5).

Fixes PR27766.

Differential Revision: http://reviews.llvm.org/D20471

v2 of r270419

llvm-svn: 270440
2016-05-23 14:57:19 +00:00
Renato Golin 2546b5ac5f Reverts "[BPF] Remove exit-on-error flag in test (PR27766)"
This patch reverts r270419 because it broke a lot of buildbots,
mostly Windows. We'd like help in investigating the issues, but
for now, it should stay out.

llvm-svn: 270433
2016-05-23 13:02:11 +00:00
Diana Picus eaf34cf67e [BPF] Remove exit-on-error flag in test (PR27766)
The exit-on-error flag on the many_args1.ll test is needed to avoid an
unreachable in BPFTargetLowering::LowerCall. We can also avoid it by ignoring
any superfluous arguments to the call (i.e. any arguments after the first 5).

Fixes PR27766

llvm-svn: 270419
2016-05-23 12:33:34 +00:00
Rafael Espindola 8c34dd8257 Delete Reloc::Default.
Having an enum member named Default is quite confusing: Is it distinct
from the others?

This patch removes that member and instead uses Optional<Reloc> in
places where we have a user input that still hasn't been maped to the
default value, which is now clear has no be one of the remaining 3
options.

llvm-svn: 269988
2016-05-18 22:04:49 +00:00
Justin Bogner f076e79388 SDAG: Implement Select instead of SelectImpl in BPFDAGToDAGISel
- Where we were returning a node before, call ReplaceNode instead.
- Where we were calling SelectNodeTo, just return afterwards.

Part of llvm.org/pr26808.

llvm-svn: 269350
2016-05-12 21:14:47 +00:00
Matthias Braun 31d19d43c7 CodeGen: Move TargetPassConfig from Passes.h to an own header; NFC
Many files include Passes.h but only a fraction needs to know about the
TargetPassConfig class. Move it into an own header. Also rename
Passes.cpp to TargetPassConfig.cpp while we are at it.

llvm-svn: 269011
2016-05-10 03:21:59 +00:00
Justin Bogner b012699741 SDAG: Rename Select->SelectImpl and repurpose Select as returning void
This is a step towards removing the rampant undefined behaviour in
SelectionDAG, which is a part of llvm.org/PR26808.

We rename SelectionDAGISel::Select to SelectImpl and update targets to
match, and then change Select to return void and consolidate the
sketchy behaviour we're trying to get away from there.

Next, we'll update backends to implement `void Select(...)` instead of
SelectImpl and eventually drop the base Select implementation.

llvm-svn: 268693
2016-05-05 23:19:08 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
Craig Topper 6ff46266d1 Declare MVT::SimpleValueType as an int8_t sized enum. This removes 400 bytes from TargetLoweringBase and probably other places.
This required changing several places to print VT enums as strings instead of raw ints since the proper method to use to print became ambiguous. This is probably an improvement anyway.

This also appears to save ~8K from an x86 self host build of llc.

llvm-svn: 266562
2016-04-17 17:37:33 +00:00
Hans Wennborg e1a2e90ffa Change eliminateCallFramePseudoInstr() to return an iterator
This will become necessary in a subsequent change to make this method
merge adjacent stack adjustments, i.e. it might erase the previous
and/or next instruction.

It also greatly simplifies the calls to this function from Prolog-
EpilogInserter. Previously, that had a bunch of logic to resume iteration
after the call; now it just continues with the returned iterator.

Note that this changes the behaviour of PEI a little. Previously,
it attempted to re-visit the new instruction created by
eliminateCallFramePseudoInstr(). That code was added in r36625,
but I can't see any reason for it: the new instructions will obviously
not be pseudo instructions, they will not have FrameIndex operands,
and we have already accounted for the stack adjustment.

Differential Revision: http://reviews.llvm.org/D18627

llvm-svn: 265036
2016-03-31 18:33:38 +00:00
Alexei Starovoitov 7e453bb8be BPF: emit an error message for unsupported signed division operation
Signed-off-by: Yonghong Song <yhs@plumgrid.com>
Signed-off-by: Alexei Starovoitov <ast@fb.com>
llvm-svn: 263842
2016-03-18 22:02:47 +00:00
Duncan P. N. Exon Smith 6307eb5518 CodeGen: TII: Take MachineInstr& in predicate API, NFC
Change TargetInstrInfo API to take `MachineInstr&` instead of
`MachineInstr*` in the functions related to predicated instructions
(I'll try to come back later and get some of the rest).  All of these
functions require non-null parameters already, so references are more
clear.  As a bonus, this happens to factor away a host of implicit
iterator => pointer conversions.

No functionality change intended.

llvm-svn: 261605
2016-02-23 02:46:52 +00:00
Oliver Stannard 7e7d983a87 Refactor backend diagnostics for unsupported features
Re-commit of r258951 after fixing layering violation.

The BPF and WebAssembly backends had identical code for emitting errors
for unsupported features, and AMDGPU had very similar code. This merges
them all into one DiagnosticInfo subclass, that can be used by any
backend.

There should be minimal functional changes here, but some AMDGPU tests
have been updated for the new format of errors (it used a slightly
different format to BPF and WebAssembly). The AMDGPU error messages will
now benefit from having precise source locations when debug info is
available.

llvm-svn: 259498
2016-02-02 13:52:43 +00:00
Oliver Stannard 02fa1c80c4 Revert r259035, it introduces a cyclic library dependency
llvm-svn: 259045
2016-01-28 13:19:47 +00:00
Oliver Stannard b4b092ea1b Add backend dignostic printer for unsupported features
Re-commit of r258951 after fixing layering violation.

The related LLVM patch adds a backend diagnostic type for reporting
unsupported features, this adds a printer for them to clang.

In the case where debug location information is not available, I've
changed the printer to report the location as the first line of the
function, rather than the closing brace, as the latter does not give the
user any information. This also affects optimisation remarks.

Differential Revision: http://reviews.llvm.org/D16590

llvm-svn: 259035
2016-01-28 10:07:27 +00:00
NAKAMURA Takumi 628a7a0aef Revert r258951 (and r258950), "Refactor backend diagnostics for unsupported features"
It broke layering violation in LLVMIR.

clang r258950 "Add backend dignostic printer for unsupported features"
llvm  r258951 "Refactor backend diagnostics for unsupported features"

llvm-svn: 259016
2016-01-28 04:41:32 +00:00
Oliver Stannard 1e67a9f196 Refactor backend diagnostics for unsupported features
The BPF and WebAssembly backends had identical code for emitting errors
for unsupported features, and AMDGPU had very similar code. This merges
them all into one DiagnosticInfo subclass, that can be used by any
backend.

There should be minimal functional changes here, but some AMDGPU tests
have been updated for the new format of errors (it used a slightly
different format to BPF and WebAssembly). The AMDGPU error messages will
now benefit from having precise source locations when debug info is
available.

The implementation of DiagnosticInfoUnsupported::print must be in
lib/Codegen rather than in the existing file in lib/IR/ to avoid
introducing a dependency from IR to CodeGen.

Differential Revision: http://reviews.llvm.org/D16590

llvm-svn: 258951
2016-01-27 17:30:33 +00:00
Benjamin Kramer f9172fd4ac Rename TargetSelectionDAGInfo into SelectionDAGTargetInfo and move it to CodeGen/
It's a SelectionDAG thing, not a Target thing.

llvm-svn: 258939
2016-01-27 16:32:26 +00:00
Chris Bieneman e49730d4ba Remove autoconf support
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html

"I felt a great disturbance in the [build system], as if millions of [makefiles] suddenly cried out in terror and were suddenly silenced. I fear something [amazing] has happened."
- Obi Wan Kenobi

Reviewers: chandlerc, grosbach, bob.wilson, tstellarAMD, echristo, whitequark

Subscribers: chfast, simoncook, emaste, jholewinski, tberghammer, jfb, danalbert, srhines, arsenm, dschuff, jyknight, dsanders, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D16471

llvm-svn: 258861
2016-01-26 21:29:08 +00:00
Rafael Espindola 8340f94df1 Convert a few assert failures into proper errors.
Fixes PR25944.

llvm-svn: 257697
2016-01-13 22:56:57 +00:00
Craig Topper daf2e3ff7a Remove extra forward declarations and scrub includes for all in tree InstPrinters. NFC
llvm-svn: 256427
2015-12-25 22:10:01 +00:00
Colin LeMahieu 8a0453e23a [AsmParser] Backends can parameterize ASM tokenization.
llvm-svn: 252439
2015-11-09 00:31:07 +00:00
Duncan P. N. Exon Smith d95fa4ccf1 BPF: Remove implicit ilist iterator conversion, NFC
llvm-svn: 250765
2015-10-20 00:02:50 +00:00
Alexei Starovoitov 87f83e6926 [bpf] Do not expand UNDEF SDNode during insn selection lowering
o Before this patch, BPF backend will expand UNDEF node
    to i64 constant 0.
  o For second pass of dag combiner, legalizer will run through
    each to-be-processed dag node.
  o If any new SDNode is generated and has an undef operand,
    dag combiner will put undef node, newly-generated constant-0 node,
    and any node which uses these nodes in the working list.
  o During this process, it is possible undef operand is
    generated again, and this will form an infinite loop
    for dag combiner pass2.
  o This patch allows UNDEF to be a legal type.

Signed-off-by: Yonghong Song <yhs@plumgrid.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
llvm-svn: 249718
2015-10-08 18:52:40 +00:00
Alexei Starovoitov 4e01a38da0 [bpf] Avoid extra pointer arithmetic for stack access
For the program like below
struct key_t {
  int pid;
  char name[16];
};
extern void test1(char *);
int test() {
  struct key_t key = {};
  test1(key.name);
  return 0;
}
For key.name, the llc/bpf may generate the below code:
  R1 = R10  // R10 is the frame pointer
  R1 += -24 // framepointer adjustment
  R1 |= 4   // R1 is then used as the first parameter of test1
OR operation is not recognized by in-kernel verifier.

This patch introduces an intermediate FI_ri instruction and
generates the following code that can be properly verified:
  R1 = R10
  R1 += -20

Patch by Yonghong Song <yhs@plumgrid.com>

llvm-svn: 249371
2015-10-06 04:00:53 +00:00
Alexei Starovoitov bf19a11116 [bpf] expand indirect branches
BPF instruction set doesn't have indirect branches. Expand them.

Reported by John Fastabend.

llvm-svn: 247951
2015-09-17 22:18:08 +00:00
Daniel Sanders 50f17235dd Revert r247692: Replace Triple with a new TargetTuple in MCTargetDesc/* and related. NFC.
Eric has replied and has demanded the patch be reverted.

llvm-svn: 247702
2015-09-15 16:17:27 +00:00
Daniel Sanders 153010c52d Re-commit r247683: Replace Triple with a new TargetTuple in MCTargetDesc/* and related. NFC.
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).

For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.

This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.

This commit also contains a trivial patch to clang to account for the C++ API
change. Thanks go to Pavel Labath for fixing LLDB for me.

Reviewers: rengolin

Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10969

llvm-svn: 247692
2015-09-15 14:08:28 +00:00
Daniel Sanders c40de48041 Revert r247684 - Replace Triple with a new TargetTuple ...
LLDB needs to be updated in the same commit.

llvm-svn: 247686
2015-09-15 13:46:21 +00:00