[arm64] Negative immediates
marc.glisse at inria.fr
Sun Sep 21 10:47:53 UTC 2014
On Sun, 21 Sep 2014, Marc Glisse wrote:
> So I guess we should not rely on it. Is this just meant to be:
> sub x1, x1, #8
This obvious change (in a dozen places in lshift/rshift) lets the build
complete, and the testsuite passes, so I'll commit it later if nobody
The compilation is quite noisy with -Wasm-operand-widths. In particular,
it complains about calling count_leading_zeros(a,b) where a has 32 bits.
The compiler is right in that the clz instruction wants 2 registers of the
same size, though I doubt it can cause any trouble.
I am also seeing it with umul_ppmm (digit, frac, frac, 10) because of the
By the way, inline asm on aarch64 confuses me, it seems important to name
the registers properly (w0 vs x0) but I only see the "r" constraint and
clang does not seem to use the type of the argument to disambiguate
between w and x.
Cross-testing aarch64 on debian has become trivial :-)
Install some regular packages (no weird download),
export CC='clang -target aarch64-linux-gnu'
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