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  1. Mar 11, 2004
  3. Mar 09, 2004
  5. Mar 08, 2004
    • Chris Lattner's avatar
      Implement folding explicit load instructions into binary operations. For a · 653e662a
      Chris Lattner authored 
      testcase like this:

int %test(int* %P, int %A) {
        %Pv = load int* %P
        %B = add int %A, %Pv
        ret int %B
}

We now generate:
test:
        mov %ECX, DWORD PTR [%ESP + 4]
        mov %EAX, DWORD PTR [%ESP + 8]
        add %EAX, DWORD PTR [%ECX]
        ret

Instead of:
test:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %ECX, DWORD PTR [%ESP + 8]
        mov %EAX, DWORD PTR [%EAX]
        add %EAX, %ECX
        ret

... saving one instruction, and often a register.  Note that there are a lot
of other instructions that could use this, but they aren't handled.  I'm not
really interested in adding them, but mul/div and all of the FP instructions
could be supported as well if someone wanted to add them.

llvm-svn: 12204
      653e662a
    • Chris Lattner's avatar
      Rearrange and refactor some code. No functionality changes. · 1dd6afe6
      Chris Lattner authored 
      llvm-svn: 12203
      1dd6afe6
  7. Mar 07, 2004
  9. Mar 04, 2004
  11. Mar 02, 2004
  13. Mar 01, 2004
    • Brian Gaeke's avatar
      TargetCacheInfo has been removed; its only uses were to propagate a constant · 427cec13
      Brian Gaeke authored 
      (16) into certain areas of the SPARC V9 back-end. I'm fairly sure the US IIIi's
dcache has 32-byte lines, so I'm not sure where the 16 came from. However, in
the interest of not breaking things any more than they already are, I'm going
to leave the constant alone.

llvm-svn: 12043
      427cec13
    • Chris Lattner's avatar
      Handle passing constant integers to functions much more efficiently. Instead · 1f4642c4
      Chris Lattner authored 
      of generating this code:

        mov %EAX, 4
        mov DWORD PTR [%ESP], %EAX
        mov %AX, 123
        movsx %EAX, %AX
        mov DWORD PTR [%ESP + 4], %EAX
        call Y

we now generate:
        mov DWORD PTR [%ESP], 4
        mov DWORD PTR [%ESP + 4], 123
        call Y

Which hurts the eyes less.  :)

Considering that register pressure around call sites is already high (with all
of the callee clobber registers n stuff), this may help a lot.

llvm-svn: 12028
      1f4642c4
    • Chris Lattner's avatar
      Fix a minor code-quality issue. When passing 8 and 16-bit integer constants · 5c7d3cda
      Chris Lattner authored 
      to function calls, we would emit dead code, like this:

int Y(int, short, double);
int X() {
  Y(4, 123, 4);
}

--- Old
X:
        sub %ESP, 20
        mov %EAX, 4
        mov DWORD PTR [%ESP], %EAX
***     mov %AX, 123
        mov %AX, 123
        movsx %EAX, %AX
        mov DWORD PTR [%ESP + 4], %EAX
        fld QWORD PTR [.CPIX_0]
        fstp QWORD PTR [%ESP + 8]
        call Y
        mov %EAX, 0
        # IMPLICIT_USE %EAX %ESP
        add %ESP, 20
        ret

Now we emit:
X:
        sub %ESP, 20
        mov %EAX, 4
        mov DWORD PTR [%ESP], %EAX
        mov %AX, 123
        movsx %EAX, %AX
        mov DWORD PTR [%ESP + 4], %EAX
        fld QWORD PTR [.CPIX_0]
        fstp QWORD PTR [%ESP + 8]
        call Y
        mov %EAX, 0
        # IMPLICIT_USE %EAX %ESP
        add %ESP, 20
        ret

Next up, eliminate the mov AX and movsx entirely!

llvm-svn: 12026
      5c7d3cda
  15. Feb 29, 2004
  17. Feb 28, 2004
  19. Feb 27, 2004