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[libc] Remove unnecessary check in printf floats #95841

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Merged
merged 1 commit into from
Jun 18, 2024
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[libc] Remove unnecessary check in printf floats #95841

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35 changes: 16 additions & 19 deletions libc/src/stdio/printf_core/float_dec_converter.h
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Original file line number Diff line number Diff line change
Expand Up @@ -502,25 +502,22 @@ LIBC_INLINE int convert_float_decimal_typed(Writer *writer,

const size_t positive_blocks = float_converter.get_positive_blocks();

if (positive_blocks >= 0) {
// This loop iterates through the number a block at a time until it finds a
// block that is not zero or it hits the decimal point. This is because all
// zero blocks before the first nonzero digit or the decimal point are
// ignored (no leading zeroes, at least at this stage).
int32_t i = static_cast<int32_t>(positive_blocks) - 1;
for (; i >= 0; --i) {
BlockInt digits = float_converter.get_positive_block(i);
if (nonzero) {
RET_IF_RESULT_NEGATIVE(float_writer.write_middle_block(digits));
} else if (digits != 0) {
size_t blocks_before_decimal = i;
float_writer.init((blocks_before_decimal * BLOCK_SIZE) +
(has_decimal_point ? 1 : 0) + precision,
blocks_before_decimal * BLOCK_SIZE);
float_writer.write_first_block(digits);

nonzero = true;
}
// This loop iterates through the number a block at a time until it finds a
// block that is not zero or it hits the decimal point. This is because all
// zero blocks before the first nonzero digit or the decimal point are
// ignored (no leading zeroes, at least at this stage).
for (int32_t i = static_cast<int32_t>(positive_blocks) - 1; i >= 0; --i) {
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If positive_blocks was 0, then i is assigned INT32_MAX and the loop is entered?

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i is signed, so if positive_blocks is 0 then i should be -1 and the loop should be skipped.

BlockInt digits = float_converter.get_positive_block(i);
if (nonzero) {
RET_IF_RESULT_NEGATIVE(float_writer.write_middle_block(digits));
} else if (digits != 0) {
size_t blocks_before_decimal = i;
float_writer.init((blocks_before_decimal * BLOCK_SIZE) +
(has_decimal_point ? 1 : 0) + precision,
blocks_before_decimal * BLOCK_SIZE);
float_writer.write_first_block(digits);

nonzero = true;
}
}

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