Mercurial > hg > octave-lojdl > gnulib-hg
changeset 8535:530583a3b054
Oops, fix ANSI C syntax error introduced in last patch.
| author | Bruno Haible <bruno@clisp.org> |
|---|---|
| date | Sun, 25 Mar 2007 12:00:37 +0000 |
| parents | 342c23c60847 |
| children | 6d78c804e54f |
| files | lib/printf-frexp.c |
| diffstat | 1 files changed, 91 insertions(+), 89 deletions(-) [+] |
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--- a/lib/printf-frexp.c +++ b/lib/printf-frexp.c @@ -85,101 +85,103 @@ exponent = MIN_EXP - 1; } # else - /* Since the exponent is an 'int', it fits in 64 bits. Therefore the - loops are executed no more than 64 times. */ - DOUBLE pow2[64]; /* pow2[i] = 2^2^i */ - DOUBLE powh[64]; /* powh[i] = 2^-2^i */ - int i; + { + /* Since the exponent is an 'int', it fits in 64 bits. Therefore the + loops are executed no more than 64 times. */ + DOUBLE pow2[64]; /* pow2[i] = 2^2^i */ + DOUBLE powh[64]; /* powh[i] = 2^-2^i */ + int i; + + exponent = 0; + if (x >= L_(1.0)) + { + /* A nonnegative exponent. */ + { + DOUBLE pow2_i; /* = pow2[i] */ + DOUBLE powh_i; /* = powh[i] */ - exponent = 0; - if (x >= L_(1.0)) - { - /* A nonnegative exponent. */ + /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i, + x * 2^exponent = argument, x >= 1.0. */ + for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5); + ; + i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i) + { + if (x >= pow2_i) + { + exponent += (1 << i); + x *= powh_i; + } + else + break; + + pow2[i] = pow2_i; + powh[i] = powh_i; + } + } + /* Here 1.0 <= x < 2^2^i. */ + } + else { - DOUBLE pow2_i; /* = pow2[i] */ - DOUBLE powh_i; /* = powh[i] */ + /* A negative exponent. */ + { + DOUBLE pow2_i; /* = pow2[i] */ + DOUBLE powh_i; /* = powh[i] */ - /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i, - x * 2^exponent = argument, x >= 1.0. */ - for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5); - ; - i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i) + /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i, + x * 2^exponent = argument, x < 1.0, exponent >= MIN_EXP - 1. */ + for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5); + ; + i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i) + { + if (exponent - (1 << i) < MIN_EXP - 1) + break; + + exponent -= (1 << i); + x *= pow2_i; + if (x >= L_(1.0)) + break; + + pow2[i] = pow2_i; + powh[i] = powh_i; + } + } + /* Here either x < 1.0 and exponent - 2^i < MIN_EXP - 1 <= exponent, + or 1.0 <= x < 2^2^i and exponent >= MIN_EXP - 1. */ + + if (x < L_(1.0)) + /* Invariants: x * 2^exponent = argument, x < 1.0 and + exponent - 2^i < MIN_EXP - 1 <= exponent. */ + while (i > 0) + { + i--; + if (exponent - (1 << i) >= MIN_EXP - 1) + { + exponent -= (1 << i); + x *= pow2[i]; + if (x >= L_(1.0)) + break; + } + } + + /* Here either x < 1.0 and exponent = MIN_EXP - 1, + or 1.0 <= x < 2^2^i and exponent >= MIN_EXP - 1. */ + } + + /* Invariants: x * 2^exponent = argument, and + either x < 1.0 and exponent = MIN_EXP - 1, + or 1.0 <= x < 2^2^i and exponent >= MIN_EXP - 1. */ + while (i > 0) + { + i--; + if (x >= pow2[i]) { - if (x >= pow2_i) - { - exponent += (1 << i); - x *= powh_i; - } - else - break; - - pow2[i] = pow2_i; - powh[i] = powh_i; + exponent += (1 << i); + x *= powh[i]; } } - /* Here 1.0 <= x < 2^2^i. */ - } - else - { - /* A negative exponent. */ - { - DOUBLE pow2_i; /* = pow2[i] */ - DOUBLE powh_i; /* = powh[i] */ - - /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i, - x * 2^exponent = argument, x < 1.0, exponent >= MIN_EXP - 1. */ - for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5); - ; - i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i) - { - if (exponent - (1 << i) < MIN_EXP - 1) - break; - - exponent -= (1 << i); - x *= pow2_i; - if (x >= L_(1.0)) - break; - - pow2[i] = pow2_i; - powh[i] = powh_i; - } - } - /* Here either x < 1.0 and exponent - 2^i < MIN_EXP - 1 <= exponent, - or 1.0 <= x < 2^2^i and exponent >= MIN_EXP - 1. */ - - if (x < L_(1.0)) - /* Invariants: x * 2^exponent = argument, x < 1.0 and - exponent - 2^i < MIN_EXP - 1 <= exponent. */ - while (i > 0) - { - i--; - if (exponent - (1 << i) >= MIN_EXP - 1) - { - exponent -= (1 << i); - x *= pow2[i]; - if (x >= L_(1.0)) - break; - } - } - - /* Here either x < 1.0 and exponent = MIN_EXP - 1, - or 1.0 <= x < 2^2^i and exponent >= MIN_EXP - 1. */ - } - - /* Invariants: x * 2^exponent = argument, and - either x < 1.0 and exponent = MIN_EXP - 1, - or 1.0 <= x < 2^2^i and exponent >= MIN_EXP - 1. */ - while (i > 0) - { - i--; - if (x >= pow2[i]) - { - exponent += (1 << i); - x *= powh[i]; - } - } - /* Here either x < 1.0 and exponent = MIN_EXP - 1, - or 1.0 <= x < 2.0 and exponent >= MIN_EXP - 1. */ + /* Here either x < 1.0 and exponent = MIN_EXP - 1, + or 1.0 <= x < 2.0 and exponent >= MIN_EXP - 1. */ + } # endif END_ROUNDING ();