Commit Graph

6 Commits

Author SHA1 Message Date
Matt Arsenault 9cac4e6d14 Rename ExpandISelPseudo->FinalizeISel, delay register reservation
This allows targets to make more decisions about reserved registers
after isel. For example, now it should be certain there are calls or
stack objects in the frame or not, which could have been introduced by
legalization.

Patch by Matthias Braun

llvm-svn: 363757
2019-06-19 00:25:39 +00:00
Matthias Braun a83403892a MachineOperand/MIParser: Do not print debug-use flag, infer it
The debug-use flag must be set exactly for uses on DBG_VALUEs.  This is
so obvious that it can be trivially inferred while parsing. This will
reduce noise when printing while omitting an information that has little
value to the user.

The parser will keep recognizing the flag for compatibility with old
`.mir` files.

Differential Revision: https://reviews.llvm.org/D53903

llvm-svn: 345671
2018-10-30 23:28:27 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Bjorn Pettersson 304877e5ec Reapply "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
Summary:
This reverts SVN r331441 (reapplies r331337), together with a fix
in to handle an already existing fragment expression in the
dbg.value that must be fragmented due to a split PHI node.

This should solve the problem seen in PR37321, which was the
reason for the revert of r331337.

The situation in PR37321 is that we have a PHI node like this

   %u.sroa = phi i80 [ %u.sroa.x, %if.x ],
                     [ %u.sroa.y, %if.y ],
                     [ %u.sroa.z, %if.z ]

and a dbg.value like this

  call void @llvm.dbg.value(metadata i80 %u.sroa,
                            metadata !13,
                            metadata !DIExpression(DW_OP_LLVM_fragment, 0, 80))

The phi node is split into three 32-bit PHI nodes

  %30:gr32 = PHI %11:gr32, %bb.4, %14:gr32, %bb.5, %27:gr32, %bb.8
  %31:gr32 = PHI %12:gr32, %bb.4, %15:gr32, %bb.5, %28:gr32, %bb.8
  %32:gr32 = PHI %13:gr32, %bb.4, %16:gr32, %bb.5, %29:gr32, %bb.8

but since the original value only is 80 bits we need to adjust the size
of the last fragment expression, and with this patch we get

  DBG_VALUE debug-use %30:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 0, 32)
  DBG_VALUE debug-use %31:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 32, 32)
  DBG_VALUE debug-use %32:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 64, 16)

Reviewers: vsk, aprantl, mstorsjo

Reviewed By: aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46384

llvm-svn: 331464
2018-05-03 17:04:16 +00:00
Martin Storsjo 67fdea490d Revert "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
This reverts SVN r331337, see PR37321 for details on the regression
it introduced.

llvm-svn: 331441
2018-05-03 07:09:33 +00:00
Bjorn Pettersson 1c5a05f32c [SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)
Summary:
This is a follow up to rL331182. A PHI node can be split up into
several MIR PHI nodes when being selected. When there is a
dbg.value intrinsic that uses the result of such a PHI node we
need to select several DBG_VALUE instructions, with fragment
expressions, in order to do a correct selection.

Reviewers: rnk, aprantl, vsk

Reviewed By: vsk

Subscribers: mattd, llvm-commits, JDevlieghere, aprantl, gbedwell, rnk

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D46329

llvm-svn: 331337
2018-05-02 06:56:38 +00:00