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
Matt Arsenault 1f795e2c2a GlobalISel: Enforce operand types for constants
A number of of tests were using imm operands, not cimm. Since CSE
relies on the exact ConstantInt* pointer used, and implicit
conversions are generally evil, also enforce the bitsize of the types.

llvm-svn: 353113
2019-02-04 23:29:31 +00:00
Diana Picus 8976ad12a9 [ARM GlobalISel] Support shifts for Thumb2
Same as ARM.

On this occasion we split some of the instruction select tests for more
complicated instructions into their own files, so we can reuse them for
ARM and Thumb mode. Likewise for the legalizer tests.

llvm-svn: 352188
2019-01-25 10:48:42 +00:00