From 94947ab1193a3b7484c77d5ce85b6645221b80e0 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Tue, 28 Jul 2015 13:13:39 -0700 Subject: Capture the consensus in #255 about 64-bit indices. --- FutureFeatures.md | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/FutureFeatures.md b/FutureFeatures.md index 8ac622e..e3f9327 100644 --- a/FutureFeatures.md +++ b/FutureFeatures.md @@ -79,13 +79,18 @@ Options under consideration: ## Linear memory bigger than 4GiB -WebAssembly will eventually allow a module to have a linear memory size greater than 4GiB by providing -load/store operations that take 64-bit index operands. Modules which opt-in to -this feature have `int64` as the canonical pointer type. - -On a 32-bit system, memory must still be smaller than 4GiB. A WebAssembly -implementation running on such a platform may restrict allocations to the lower -4GiB, and leave the two 32-bits untouched. +WebAssembly will eventually allow a module to have a linear memory size greater +than 4GiB by providing load/store/etc. operations that take 64-bit index +operands. + +Of course, the ability to actually allocate this much memory will always be +subject to dynamic resource availability. + +Initially, it will likely be required that a program use all 32-bit indices or +all 64-bit indices, and not a mix of both, so that implementations don't have +to support both at the same time. However, operators with 32-bit indices and +operations with 64-bit indices will be given separate names to leave open the +possibility of supporting both in the same program. ## Source maps integration -- cgit v1.2.3 From f79a4fc01b1fed68c70f9f473dc0d088c760c00d Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Tue, 28 Jul 2015 14:09:13 -0700 Subject: Minor wording fixes. --- FutureFeatures.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/FutureFeatures.md b/FutureFeatures.md index e3f9327..67e1468 100644 --- a/FutureFeatures.md +++ b/FutureFeatures.md @@ -88,9 +88,9 @@ subject to dynamic resource availability. Initially, it will likely be required that a program use all 32-bit indices or all 64-bit indices, and not a mix of both, so that implementations don't have -to support both at the same time. However, operators with 32-bit indices and +to support both in the same program. However, operators with 32-bit indices and operations with 64-bit indices will be given separate names to leave open the -possibility of supporting both in the same program. +possibility of supporting both in the same program in the future. ## Source maps integration -- cgit v1.2.3