Commit Graph

3 Commits

Author SHA1 Message Date
Sjoerd Meijer 7efabe5c7d [MIR][ARM] MachineOperand comments
This adds infrastructure to print and parse MIR MachineOperand comments.
The motivation for the ARM backend is to print condition code names instead of
magic constants that are difficult to read (for human beings). For example,
instead of this:

  dead renamable $r2, $cpsr = tEOR killed renamable $r2, renamable $r1, 14, $noreg
  t2Bcc %bb.4, 0, killed $cpsr

we now print this:

  dead renamable $r2, $cpsr = tEOR killed renamable $r2, renamable $r1, 14 /* CC::always */, $noreg
  t2Bcc %bb.4, 0 /* CC:eq */, killed $cpsr

This shows that MachineOperand comments are enclosed between /* and */. In this
example, the EOR instruction is not conditionally executed (i.e. it is "always
executed"), which is encoded by the 14 immediate machine operand. Thus, now
this machine operand has /* CC::always */ as a comment. The 0 on the next
conditional branch instruction represents the equal condition code, thus now
this operand has /* CC:eq */ as a comment.

As it is a comment, the MI lexer/parser completely ignores it. The benefit is
that this keeps the change in the lexer extremely minimal and no target
specific parsing needs to be done. The changes on the MIPrinter side are also
minimal, as there is only one target hooks that is used to create the machine
operand comments.

Differential Revision: https://reviews.llvm.org/D74306
2020-02-24 14:19:21 +00:00
Sander de Smalen 5d6ee76c16 Describe stack-id as an enum
This patch changes MIR stack-id from an integer to an enum,
and adds printing/parsing support for this in MIR files. The default
stack-id '0' is now renamed to 'default'.

This should make MIR tests that have stack objects with different stack-ids
more descriptive. It also clarifies code operating on StackID.

Reviewers: arsenm, thegameg, qcolombet

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D60137

llvm-svn: 363533
2019-06-17 09:13:29 +00:00
David Green c519d3c403 [ARM] Update check for CBZ in Ifcvt
The check for creating CBZ in constant island pass recently obtained the
ability to search backwards to find a Cmp instruction. The code in IfCvt should
mirror this to allow more conversions to the smaller form. The common code has
been pulled out into a separate function to be shared between the two places.

Differential Revision: https://reviews.llvm.org/D60090

llvm-svn: 358977
2019-04-23 12:11:26 +00:00