Remove support for 8 or 16 bit BigInt words

It turned out 8 bit was very broken (failed to compile, due to
overload problems with functions taking uint8_t vs word).
16 bit words work aside from a test failure, but is really slow.

Practically speaking we are not in a position to support 16-bit CPUs
very well. And being able to assume sizeof(word) >= sizeof(uint32_t)
allows simplifying some code.

1 files changed, 2 insertions, 6 deletions

diff --git a/src/lib/math/numbertheory/nistp_redc.cpp b/src/lib/math/numbertheory/nistp_redc.cpp
index b74a2f9c6..1c2855784 100644
--- a/src/lib/math/numbertheory/nistp_redc.cpp
+++ b/src/lib/math/numbertheory/nistp_redc.cpp
@@ -91,10 +91,8 @@ inline uint32_t get_uint32_t(const BigInt& x, size_t i)
    {
 #if (BOTAN_MP_WORD_BITS == 32)
    return x.word_at(i);
-#elif (BOTAN_MP_WORD_BITS == 64)
-   return static_cast<uint32_t>(x.word_at(i/2) >> ((i % 2)*32));
 #else
-  #error "Not implemented"
+   return static_cast<uint32_t>(x.word_at(i/2) >> ((i % 2)*32));
 #endif
    }
 
@@ -103,10 +101,8 @@ inline void set_words(BigInt& x, size_t i, uint32_t R0, uint32_t R1)
 #if (BOTAN_MP_WORD_BITS == 32)
    x.set_word_at(i, R0);
    x.set_word_at(i+1, R1);
-#elif (BOTAN_MP_WORD_BITS == 64)
-   x.set_word_at(i/2, (static_cast<uint64_t>(R1) << 32) | R0);
 #else
-  #error "Not implemented"
+   x.set_word_at(i/2, (static_cast<uint64_t>(R1) << 32) | R0);
 #endif
    }