Commit Graph

8 Commits

Author SHA1 Message Date
Toma Tabacu
cb43f81fc5 [mips] Add assembler support for the "la $reg,symbol" pseudo-instruction.
Summary:
This pseudo-instruction allows the programmer to load an address from a symbolic expression into a register.

Patch by David Chisnall.
His work was sponsored by: DARPA, AFRL

I've made some minor changes to the original, such as improving the formatting and adding some comments, and I've also added a test case.

Reviewers: dsanders

Reviewed By: dsanders

Differential Revision: http://reviews.llvm.org/D4808

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215630 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-14 10:29:17 +00:00
Matheus Almeida
c39b18b306 [mips] Fix expansion of memory operation if destination register is not a GPR.
Summary:
The assembler tries to reuse the destination register for memory operations whenever
it can but it's not possible to do so if the destination register is not a GPR.

Example:
  ldc1 $f0, sym
should expand to:
  lui $at, %hi(sym)
  ldc1 $f0, %lo(sym)($at)

It's entirely wrong to expand to:
  lui $f0, %hi(sym)
  ldc1 $f0, %lo(sym)($f0)

Reviewers: dsanders

Reviewed By: dsanders

Differential Revision: http://reviews.llvm.org/D4173

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211169 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-18 14:49:56 +00:00
Matheus Almeida
7047ad9a08 [mips] Access $at only if necessary.
Summary:
This patch doesn't really change the logic behind expandMemInst but it allows
us to assemble .S files that use .set noat with some macros. For example:

.set noat
lw $k0, offset($k1)

Can expand to:
lui	$k0, %hi(offset)
addu	$k0, $k0, $k1
lw	$k0, %lo(offset)($k0)

with no need to access $at.

Reviewers: dsanders, vmedic

Reviewed By: dsanders, vmedic

Differential Revision: http://reviews.llvm.org/D4159

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211165 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-18 14:15:42 +00:00
Matheus Almeida
20887ffc80 [mips] Update MipsAsmParser so that it's possible to handle immediates that start with the binary operator NOT (~).
Reviewers: dsanders

Reviewed By: dsanders

Differential Revision: http://reviews.llvm.org/D4158

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211163 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-18 13:55:18 +00:00
Nico Rieck
ef1762b6a1 Use object file specific section type for initial text section
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179494 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-14 21:18:36 +00:00
Jack Carter
25df6a93f3 This patch that enables the Mips assembler to use symbols for offset for instructions
This patch uses the generated instruction info tables to 
identify memory/load store instructions.
After successful matching and based on the operand type 
and size, it generates additional instructions to the output.

Contributor: Vladimir Medic



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177685 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 00:05:30 +00:00
Jack Carter
2f68b311a1 Initial assembler implementation of Mips load address macro
This patch provides initial implementation of load address 
macro instruction for Mips. We have implemented two kinds 
of expansions with their variations depending on the size 
of immediate operand:

 1) load address with immediate value directly:
    * la d,j => addiu d,$zero,j   (for -32768 <= j <= 65535)
    * la d,j => lui d,hi16(j)
                ori d,d,lo16(j)   (for any other 32 bit value of j)

 2) load load address with register offset value
    * la d,j(s) => addiu d,s,j     (for -32768 <= j <= 65535)
    * la d,j(s) => lui d,hi16(j)   (for any other 32 bit value of j)
                   ori d,d,lo16(j)
                   addu d,d,s

This patch does not cover the case when the address is loaded 
from the value of the label or function.

Contributer: Vladimir Medic


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165561 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-09 23:29:45 +00:00
Jack Carter
9d577c8614 Implement methods that enable expansion of load immediate
macro instruction (li) in the assembler.

We have identified three possible expansions depending on 
the size of immediate operand:
  1) for 0 ≤ j ≤ 65535.
     li d,j =>
     ori d,$zero,j

  2) for −32768 ≤ j < 0.
     li d,j =>
     addiu d,$zero,j

  3) for any other value of j that is representable as a 32-bit integer.
     li d,j =>
     lui d,hi16(j)
     ori d,d,lo16(j)

All of the above have been implemented in ths patch.

Contributer: Vladimir Medic


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165199 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-04 04:03:53 +00:00