From 84dd0b3fad14e583e03067a0b73c2017b00d2a8a Mon Sep 17 00:00:00 2001 From: Sanjay Patel Date: Tue, 3 Apr 2018 13:05:20 +0000 Subject: [PATCH] [LangRef] fix description and examples of fptrunc As noted in PR36966: https://bugs.llvm.org/show_bug.cgi?id=36966 The old description doesn't match what we do in code, so this just fixes the documentation to avoid confusion. Differential Revision: https://reviews.llvm.org/D45190 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@329065 91177308-0d34-0410-b5e6-96231b3b80d8 --- docs/LangRef.rst | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/docs/LangRef.rst b/docs/LangRef.rst index 035019499c1..62fdda91218 100644 --- a/docs/LangRef.rst +++ b/docs/LangRef.rst @@ -8371,18 +8371,17 @@ Semantics: The '``fptrunc``' instruction casts a ``value`` from a larger :ref:`floating-point ` type to a smaller :ref:`floating-point -` type. If the value cannot fit (i.e. overflows) within the -destination type, ``ty2``, then the results are undefined. If the cast produces -an inexact result, how rounding is performed (e.g. truncation, also known as -round to zero) is undefined. +` type. +This instruction is assumed to execute in the default :ref:`floating-point +environment `. Example: """""""" .. code-block:: llvm - %X = fptrunc double 123.0 to float ; yields float:123.0 - %Y = fptrunc double 1.0E+300 to float ; yields undefined + %X = fptrunc double 16777217.0 to float ; yields float:16777216.0 + %Y = fptrunc double 1.0E+300 to half ; yields half:+infinity '``fpext .. to``' Instruction ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -- 2.11.0