From: Oded Gabbay Date: Thu, 3 Sep 2015 16:00:26 +0000 (+0300) Subject: llvmpipe: convert double to long long instead of unsigned long long X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=4f2290d1612569686284609059d29a85c9de67cf;p=mesa.git llvmpipe: convert double to long long instead of unsigned long long round(val*dscale) produces a double result, as val and dscale are double. However, LLVMConstInt receives unsigned long long, so there is an implicit conversion from double to unsigned long long. This is an undefined behavior. Therefore, we need to first explicitly convert the round result to long long, and then let the compiler handle conversion from that to unsigned long long. This bug manifests itself in POWER, where all IMM values of -1 are being converted to 0 implicitly, causing a wrong LLVM IR output. Signed-off-by: Oded Gabbay CC: "10.6 11.0" Reviewed-by: Tom Stellard Reviewed-by: Roland Scheidegger --- diff --git a/src/gallium/auxiliary/gallivm/lp_bld_const.c b/src/gallium/auxiliary/gallivm/lp_bld_const.c index 0f5a8f8e851..9cd7c5553cf 100644 --- a/src/gallium/auxiliary/gallivm/lp_bld_const.c +++ b/src/gallium/auxiliary/gallivm/lp_bld_const.c @@ -311,7 +311,7 @@ lp_build_const_elem(struct gallivm_state *gallivm, else { double dscale = lp_const_scale(type); - elem = LLVMConstInt(elem_type, round(val*dscale), 0); + elem = LLVMConstInt(elem_type, (long long) round(val*dscale), 0); } return elem;