[LLVMdev] Converting into SSA form

Eli Friedman eli.friedman at gmail.com
Mon Jun 7 12:00:39 PDT 2010

On Mon, Jun 7, 2010 at 2:09 AM, Chayan Sarkar <chayan.ju at gmail.com> wrote:
> E-path PRE requires the program in SSA form like SSAPRE algorithm.
> Then it finds the eliminatable path (e-path) for an expression and
> converts partially redundant to fully redundant and removes redundancy

An SSA-based algorithm is usually expressed in terms of SSA registers,
not variables from before conversion to SSA, but I won't question your

If you want control over the mem2reg process, don't use the pass; you
can call llvm::PromoteMemToReg directly.


> Chayan
> On Mon, Jun 7, 2010 at 1:58 PM, Eli Friedman <eli.friedman at gmail.com> wrote:
>> On Sun, Jun 6, 2010 at 8:56 PM, Chayan Sarkar <chayan.ju at gmail.com> wrote:
>>> Hi Jeffrey,
>>> Actually I am trying to implement "E-path PRE" which is based on
>>> non-algebric equivallence. So, the  variable names need to be
>>> preserved.
>> Then why do you want to run mem2reg before your optimization in the first place?
>> -Eli

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