Closed Bug 686106 Opened 12 years ago Closed 12 years ago

JM: don't allocate an extra register for JSOP_MUL if one operand is constant

Categories

(Core :: JavaScript Engine, defect)

Product:
Core
Component:
JavaScript Engine
Type:
defect
Priority:
Not set
Severity:
normal

Tracking

()

Status:
RESOLVED FIXED
Milestone:
mozilla9

People

(Reporter: jandem, Assigned: jandem)

References

Details

(Keywords: perf)

Attachments

(1 file, 1 obsolete file)

Patch
5.25 KB, patch
bhackett1024
: review+
Details | Diff | Splinter Review 
Currently we allocate an extra register for JSOP_MUL if one operand is constant. We do this because (quote) "not all CPUs have multiplication on immediates"

GCC just generates a 3-operand IMUL instruction, and the x86, ARM and Sparc assemblers already support this (the ARM implementation uses a scratch register).
Attached patch Patch (obsolete) — — Splinter Review 

        Attachment #559675 -
        Flags: review?(bhackett1024)

    
    

    
  

      
      
      
      

        Attached patch
          
          
        Patch
        — 
          — Splinter Review
      

    


  

        Attachment #559675 -
        Attachment is obsolete: true

        Attachment #559675 -
        Flags: review?(bhackett1024)

        Attachment #559676 -
        Flags: review?(bhackett1024)

    
    

    
  
Comment on attachment 559676 [details] [diff] [review]
Patch

Yeah, differences in the supported instruction set should be abstracted away by the assembler as much as possible (see also: AbsoluteAddress on x86 vs. x64).

        Attachment #559676 -
        Flags: review?(bhackett1024) → review+

    
    

    
  
http://hg.mozilla.org/integration/mozilla-inbound/rev/5079bd3f82bf
Whiteboard: [inbound]
Target Milestone: --- → mozilla9

    
    

    
  
https://hg.mozilla.org/mozilla-central/rev/5079bd3f82bf
Status: ASSIGNED → RESOLVED
Closed: 12 years ago
Resolution: --- → FIXED
Whiteboard: [inbound]

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