The reason these commits bring it up is that I don’t see it clearly documented
whether:
float x = 340282356779733661637539395458142568447.0;
is interpreted as
float x = 340282356779733661637539395458142568447.0f; // x is FLT_MAX
or as
float x = (float)(340282356779733661637539395458142568447.0); // x is
INFINITY
when the no-fp64 mode is active. I assume that only one of these is the
correct behavior, and we should have a regression test that will flag the error
if it changes.
– Steve
> On Nov 15, 2016, at 4:51 AM, Neil Hickey <neil.hic...@arm.com> wrote:
>
> It would be valuable to perform that test, if clang tests don't already do
> this, though I'm not sure it should be part of this particular commit as all
> this commit should do is change the casts if the target doesn't support
> double.
>
> Neil
>
>> -----Original Message-----
>> From: sca...@apple.com [mailto:sca...@apple.com]
>> Sent: 14 November 2016 16:01
>> To: Neil Hickey
>> Cc: cfe-commits@lists.llvm.org
>> Subject: Re: r286815 - Improve handling of floating point literals in OpenCL
>> to
>> only use double precision if the target supports fp64.
>>
>> Can you add some non-trivial test cases that exercise double-rounding,
>> especially near the overflow boundary?
>>
>> e.g. What is the expected value of x if the target does not support fp64?:
>>
>> float x = 340282356779733661637539395458142568447.0;
>>
>> – Steve
>>
>>> On Nov 14, 2016, at 6:15 AM, Neil Hickey via cfe-commits <cfe-
>> comm...@lists.llvm.org> wrote:
>>>
>>> Author: neil.hickey
>>> Date: Mon Nov 14 05:15:51 2016
>>> New Revision: 286815
>>>
>>> URL: http://llvm.org/viewvc/llvm-project?rev=286815&view=rev
>>> Log:
>>> Improve handling of floating point literals in OpenCL to only use double
>> precision if the target supports fp64.
>>>
>>> This change makes sure single-precision floating point types are used
>>> if the
>>> cl_fp64 extension is not supported by the target.
>>>
>>> Also removed the check to see whether the OpenCL version is >= 1.2, as
>>> this has been incorporated into the extension setting code.
>>>
>>> Differential Revision: https://reviews.llvm.org/D24235
>>>
>>>
>>> Modified:
>>> cfe/trunk/lib/Sema/SemaExpr.cpp
>>> cfe/trunk/lib/Sema/SemaType.cpp
>>> cfe/trunk/test/CodeGenOpenCL/fpmath.cl
>>> cfe/trunk/test/SemaOpenCL/extensions.cl
>>>
>>> Modified: cfe/trunk/lib/Sema/SemaExpr.cpp
>>> URL:
>>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExpr.cpp?re
>>> v=286815&r1=286814&r2=286815&view=diff
>>>
>> ==========================================================
>> ============
>>> ========
>>> --- cfe/trunk/lib/Sema/SemaExpr.cpp (original)
>>> +++ cfe/trunk/lib/Sema/SemaExpr.cpp Mon Nov 14 05:15:51 2016
>>> @@ -705,9 +705,13 @@ ExprResult Sema::DefaultLvalueConversion if
>>> (getLangOpts().ObjCAutoRefCount &&
>>> E->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
>>> Cleanup.setExprNeedsCleanups(true);
>>> +
>>> + ExprResult Res = E;
>>>
>>> - ExprResult Res = ImplicitCastExpr::Create(Context, T,
>> CK_LValueToRValue, E,
>>> - nullptr, VK_RValue);
>>> + if ( T != E->getType()) {
>>> + Res = ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, E,
>>> + nullptr, VK_RValue); }
>>>
>>> // C11 6.3.2.1p2:
>>> // ... if the lvalue has atomic type, the value has the non-atomic version
>>> @@ -817,8 +821,16 @@ ExprResult Sema::DefaultArgumentPromotio //
>>> double.
>>> const BuiltinType *BTy = Ty->getAs<BuiltinType>(); if (BTy &&
>>> (BTy->getKind() == BuiltinType::Half ||
>>> - BTy->getKind() == BuiltinType::Float))
>>> - E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).get();
>>> + BTy->getKind() == BuiltinType::Float)) {
>>> + if (getLangOpts().OpenCL &&
>>> + !(getOpenCLOptions().cl_khr_fp64)) {
>>> + if (BTy->getKind() == BuiltinType::Half) {
>>> + E = ImpCastExprToType(E, Context.FloatTy,
>>> CK_FloatingCast).get();
>>> + }
>>> + } else {
>>> + E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).get();
>>> + }
>>> + }
>>>
>>> // C++ performs lvalue-to-rvalue conversion as a default argument //
>>> promotion, even on class types, but note:
>>> @@ -3397,10 +3409,13 @@ ExprResult Sema::ActOnNumericConstant(co
>>>
>>> if (Ty == Context.DoubleTy) {
>>> if (getLangOpts().SinglePrecisionConstants) {
>>> - Res = ImpCastExprToType(Res, Context.FloatTy,
>> CK_FloatingCast).get();
>>> + const BuiltinType *BTy = Ty->getAs<BuiltinType>();
>>> + if (BTy->getKind() != BuiltinType::Float) {
>>> + Res = ImpCastExprToType(Res, Context.FloatTy,
>> CK_FloatingCast).get();
>>> + }
>>> } else if (getLangOpts().OpenCL &&
>>> - !((getLangOpts().OpenCLVersion >= 120) ||
>>> - getOpenCLOptions().cl_khr_fp64)) {
>>> + !(getOpenCLOptions().cl_khr_fp64)) {
>>> + // Impose single-precision float type when cl_khr_fp64 is not
>>> enabled.
>>> Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64);
>>> Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).get();
>>> }
>>>
>>> Modified: cfe/trunk/lib/Sema/SemaType.cpp
>>> URL:
>>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaType.cpp?re
>>> v=286815&r1=286814&r2=286815&view=diff
>>>
>> ==========================================================
>> ============
>>> ========
>>> --- cfe/trunk/lib/Sema/SemaType.cpp (original)
>>> +++ cfe/trunk/lib/Sema/SemaType.cpp Mon Nov 14 05:15:51 2016
>>> @@ -1402,8 +1402,7 @@ static QualType ConvertDeclSpecToType(Ty
>>> Result = Context.DoubleTy;
>>>
>>> if (S.getLangOpts().OpenCL &&
>>> - !((S.getLangOpts().OpenCLVersion >= 120) ||
>>> - S.getOpenCLOptions().cl_khr_fp64)) {
>>> + !(S.getOpenCLOptions().cl_khr_fp64)) {
>>> S.Diag(DS.getTypeSpecTypeLoc(), diag::err_type_requires_extension)
>>> << Result << "cl_khr_fp64";
>>> declarator.setInvalidType(true);
>>>
>>> Modified: cfe/trunk/test/CodeGenOpenCL/fpmath.cl
>>> URL:
>>> http://llvm.org/viewvc/llvm-
>> project/cfe/trunk/test/CodeGenOpenCL/fpmat
>>> h.cl?rev=286815&r1=286814&r2=286815&view=diff
>>>
>> ==========================================================
>> ============
>>> ========
>>> --- cfe/trunk/test/CodeGenOpenCL/fpmath.cl (original)
>>> +++ cfe/trunk/test/CodeGenOpenCL/fpmath.cl Mon Nov 14 05:15:51 2016
>>> @@ -1,5 +1,6 @@
>>> // RUN: %clang_cc1 %s -emit-llvm -o - -triple spir-unknown-unknown |
>>> FileCheck --check-prefix=CHECK --check-prefix=NODIVOPT %s // RUN:
>>> %clang_cc1 %s -emit-llvm -o - -triple spir-unknown-unknown
>>> -cl-fp32-correctly-rounded-divide-sqrt | FileCheck
>>> --check-prefix=CHECK --check-prefix=DIVOPT %s
>>> +// RUN: %clang_cc1 %s -emit-llvm -o - -DNOFP64 -cl-std=CL1.1 -triple
>>> +r600-unknown-unknown -target-cpu r600 -pedantic | FileCheck
>>> +--check-prefix=CHECK-DBL %s
>>>
>>> typedef __attribute__(( ext_vector_type(4) )) float float4;
>>>
>>> @@ -21,14 +22,26 @@ float4 spvectordiv(float4 a, float4 b) { return a
>>> / b; }
>>>
>>> +void printf(constant char* fmt, ...);
>>> +
>>> +#ifndef NOFP64
>>> #pragma OPENCL EXTENSION cl_khr_fp64 : enable
>>> +#endif
>>> +void testdbllit(long *val) {
>>> + // CHECK-DBL: float 2.000000e+01
>>> + // CHECK: double 2.000000e+01
>>> + printf("%f", 20.0);
>>> +}
>>>
>>> +#ifndef NOFP64
>>> +#pragma OPENCL EXTENSION cl_khr_fp64 : enable
>>> double dpscalardiv(double a, double b) { // CHECK: @dpscalardiv //
>>> CHECK: #[[ATTR]] // CHECK-NOT: !fpmath return a / b; }
>>> +#endif
>>>
>>> // CHECK: attributes #[[ATTR]] = {
>>> // NODIVOPT: "correctly-rounded-divide-sqrt-fp-math"="false"
>>>
>>> Modified: cfe/trunk/test/SemaOpenCL/extensions.cl
>>> URL:
>>> http://llvm.org/viewvc/llvm-
>> project/cfe/trunk/test/SemaOpenCL/extensio
>>> ns.cl?rev=286815&r1=286814&r2=286815&view=diff
>>>
>> ==========================================================
>> ============
>>> ========
>>> --- cfe/trunk/test/SemaOpenCL/extensions.cl (original)
>>> +++ cfe/trunk/test/SemaOpenCL/extensions.cl Mon Nov 14 05:15:51 2016
>>> @@ -1,5 +1,6 @@
>>> // RUN: %clang_cc1 %s -triple spir-unknown-unknown -verify -pedantic
>>> -fsyntax-only // RUN: %clang_cc1 %s -triple spir-unknown-unknown
>>> -verify -pedantic -fsyntax-only -cl-std=CL1.1
>>> +// RUN: %clang_cc1 %s -triple spir-unknown-unknown -verify -pedantic
>>> +-fsyntax-only -cl-std=CL1.2 -DFP64
>>>
>>> // Test with a target not supporting fp64.
>>> // RUN: %clang_cc1 %s -triple r600-unknown-unknown -target-cpu r600
>>> -verify -pedantic -fsyntax-only -DNOFP64 -DNOFP16 @@ -21,12 +22,16 @@
>>> // RUN: %clang_cc1 %s -triple spir-unknown-unknown -verify -pedantic
>>> -fsyntax-only -cl-ext=-all -cl-ext=+cl_khr_fp64 -cl-ext=+cl_khr_fp16
>>> -cl-ext=-cl_khr_fp64 -DNOFP64 // RUN: %clang_cc1 %s -triple
>>> spir-unknown-unknown -verify -pedantic -fsyntax-only -cl-ext=-all
>>> -cl-ext=+cl_khr_fp64,-cl_khr_fp64,+cl_khr_fp16 -DNOFP64
>>>
>>> +#ifdef FP64
>>> +// expected-no-diagnostics
>>> +#endif
>>>
>>> -
>>> +#if __OPENCL_C_VERSION__ < 120
>>> void f1(double da) { // expected-error {{type 'double' requires
>>> cl_khr_fp64 extension}} double d; // expected-error {{type 'double'
>>> requires cl_khr_fp64 extension}}
>>> (void) 1.0; // expected-warning {{double precision constant requires
>>> cl_khr_fp64}} }
>>> +#endif
>>>
>>> #pragma OPENCL EXTENSION cl_khr_fp64 : enable #ifdef NOFP64 @@ -
>> 45,8
>>> +50,9 @@ void f2(void) { #endif
>>>
>>> (void) 1.0;
>>> +
>>> #ifdef NOFP64
>>> -// expected-warning@-2{{double precision constant requires
>>> cl_khr_fp64, casting to single precision}}
>>> +// expected-warning@-6{{double precision constant requires
>>> +cl_khr_fp64, casting to single precision}}
>>> #endif
>>> }
>>>
>>> @@ -55,6 +61,8 @@ void f2(void) {
>>> // expected-warning@-2{{unsupported OpenCL extension 'cl_khr_fp64' -
>>> ignoring}} #endif
>>>
>>> +#if __OPENCL_C_VERSION__ < 120
>>> void f3(void) {
>>> double d; // expected-error {{type 'double' requires cl_khr_fp64
>>> extension}} }
>>> +#endif
>>>
>>>
>>> _______________________________________________
>>> cfe-commits mailing list
>>> cfe-commits@lists.llvm.org
>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>
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