MatCat.OpenSource/8sa1-gcc
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

(expand_binop): For complex mult, compute res in each alternative, not before.

Browse Source 
From-SVN: r3165
This commit is contained in:
Richard Stallman 1993-01-09 08:51:21 +00:00
parent 676ce22316
commit 96f153da76
1 changed files with 12 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
gcc/optabs.c
View File

@ -889,7 +889,9 @@ expand_binop (mode, binoptab, op0, op1, target, unsignedp, methods)
switch (binoptab->code) switch (binoptab->code)
{ {
case PLUS: case PLUS:
/* (a+ib) + (c+id) = (a+c) + i(b+d) */
case MINUS: case MINUS:
/* (a+ib) - (c+id) = (a-c) + i(b-d) */
res = expand_binop (submode, binoptab, real0, real1, res = expand_binop (submode, binoptab, real0, real1,
realr, unsignedp, methods); realr, unsignedp, methods);
if (res != realr) if (res != realr)
@ -912,15 +914,14 @@ expand_binop (mode, binoptab, op0, op1, target, unsignedp, methods)
case MULT: case MULT:
/* (a+ib) * (c+id) = (ac-bd) + i(ad+cb) */ /* (a+ib) * (c+id) = (ac-bd) + i(ad+cb) */
res = expand_binop (submode, binoptab, real0, real1,
realr, unsignedp, methods);
if (imag0 && imag1) if (imag0 && imag1)
{ {
rtx temp = rtx temp =
expand_binop (submode, sub_optab, res, expand_binop (submode, sub_optab,
expand_binop (submode, binoptab, imag0, imag1, expand_binop (submode, binoptab, real0,
0, unsignedp, methods), real1, 0, unsignedp, methods),
expand_binop (submode, binoptab, imag0,
imag1, 0, unsignedp, methods),
realr, unsignedp, methods); realr, unsignedp, methods);
if (temp != realr) if (temp != realr)
@ -939,6 +940,8 @@ expand_binop (mode, binoptab, op0, op1, target, unsignedp, methods)
} }
else else
{ {
res = expand_binop (submode, binoptab, real0, real1,
realr, unsignedp, methods);
if (res != realr) if (res != realr)
emit_move_insn (realr, res); emit_move_insn (realr, res);
@ -954,11 +957,11 @@ expand_binop (mode, binoptab, op0, op1, target, unsignedp, methods)
break; break;
case DIV: case DIV:
/* (c+id)/(a+ib) == ((c+id)*(a-ib))/(a*a+b*b) */ /* (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd)) */
if (! imag1) if (! imag1)
{ { /* (a+ib) / (c+i0) = (a/c) + i(b/c) */
/* Simply divide the real and imaginary parts by `a' */ /* Simply divide the real and imaginary parts by `c' */
res = expand_binop (submode, binoptab, real0, real1, res = expand_binop (submode, binoptab, real0, real1,
realr, unsignedp, methods); realr, unsignedp, methods);
if (res != realr) if (res != realr)