diff options
Diffstat (limited to 'src/Libraries/Math/Isqrt.cpp')
| -rw-r--r-- | src/Libraries/Math/Isqrt.cpp | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/src/Libraries/Math/Isqrt.cpp b/src/Libraries/Math/Isqrt.cpp index 4feb0d96..3c8bb990 100644 --- a/src/Libraries/Math/Isqrt.cpp +++ b/src/Libraries/Math/Isqrt.cpp @@ -1,8 +1,5 @@ #include "RepRapFirmware.h" -// The remaining functions are speed-critical, so use full optimisation -#pragma GCC optimize ("O3") - // Fast 62-bit integer square root function (thanks dmould) uint32_t isqrt64(uint64_t num) { @@ -58,7 +55,7 @@ uint32_t isqrt64(uint64_t num) iter64a(14) iter64a(12) iter64a(10) iter64a(8) iter64a(6) iter64a(4) iter64a(2) iter64a(0) - // resHigh is twice the square root of the msw, in the range 0..2^17-1 + // resHigh is twice the square root of the msw, in the range 0..2^16-1 with the input restricted to 62 bits uint64_t numAll = ((uint64_t)numHigh << 32) | (uint32_t)num; #define iter64b(N) \ @@ -74,7 +71,7 @@ uint32_t isqrt64(uint64_t num) // We need to do 16 iterations. // After the last iteration, numAll may be between 0 and (1 + 2 * res) inclusive. - // So to take square roots of numbers up to 64 bits, we need to do all these iterations using 64 bit maths. + // So to take square roots of numbers up to 62 bits, we need to do all these iterations using 64 bit maths. // If we restricted the input to e.g. 48 bits, then we could do some of the final iterations using 32-bit maths. iter64b(30) iter64b(28) iter64b(26) iter64b(24) iter64b(22) iter64b(20) iter64b(18) iter64b(16) |