[FPEnv] Enable strict fp for AArch64 in clang

[john.brawn]

Summary

The AArch64 target now has the necessary support for strict fp, so enable it in clang.

[ostannard]

clang/docs/ReleaseNotes.rst

769

Do we need tests for these command-line options? I only see tests for -ffp-exception-behavior= in this patch.

[john.brawn]

clang/docs/ReleaseNotes.rst

769

-ftrapping-math and -ffp-model=strict are both driver-only options that are converted into other cc1 options and tested in Driver/fp-model.c. -frounding-math is tested in a target-independent way in the CodeGen/fpconstrained* tests.

[olista01]

LGTM

clang/docs/ReleaseNotes.rst

 - ``-march`` values for targeting armv2, armv2A, armv3 and armv3M have been removed.
   Their presence gave the impression that Clang can correctly generate code for
   them, which it cannot.
 - Support has been added for the following processors (-mcpu identifiers in parenthesis):
 
   * Arm Cortex-A715 (cortex-a715).
   * Arm Cortex-X3 (cortex-x3).
   * Arm Neoverse V2 (neoverse-v2)
+- Strict floating point has been enabled for AArch64, which means that
+  ``-ftrapping-math``, ``-frounding-math``, ``-ffp-model=strict``, and
+  ``-ffp-exception-behaviour=<arg>`` are now accepted.
 
 Floating Point Support in Clang
 -------------------------------
 - The driver option ``-menable-unsafe-fp-math`` has been removed. To enable
   unsafe floating-point optimizations use ``-funsafe-math-optimizations`` or
   ``-ffast-math`` instead.
 - Add ``__builtin_elementwise_sin`` and ``__builtin_elementwise_cos`` builtins for floating point types only.
 

clang/lib/Basic/Targets/AArch64.cpp

if (getTriple().isOSOpenBSD()) {
     Int64Type = SignedLong;
     IntMaxType = SignedLong;
   }
 
   // All AArch64 implementations support ARMv8 FP, which makes half a legal type.
   HasLegalHalfType = true;
   HalfArgsAndReturns = true;
   HasFloat16 = true;
+  HasStrictFP = true;
 
   if (Triple.isArch64Bit())
     LongWidth = LongAlign = PointerWidth = PointerAlign = 64;
   else
     LongWidth = LongAlign = PointerWidth = PointerAlign = 32;
 
   MaxVectorAlign = 128;
   MaxAtomicInlineWidth = 128;

clang/test/CodeGen/aarch64-neon-intrinsics-constrained.c

 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon \
 // RUN:     -S -disable-O0-optnone \
 // RUN:  -flax-vector-conversions=none -emit-llvm -o - %s | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefixes=COMMON,COMMONIR,UNCONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon \
 // RUN:     -S -disable-O0-optnone \
-// RUN:  -ffp-exception-behavior=strict -fexperimental-strict-floating-point \
+// RUN:  -ffp-exception-behavior=strict \
 // RUN:  -flax-vector-conversions=none -emit-llvm -o - %s | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefixes=COMMON,COMMONIR,CONSTRAINED %s
 
 // REQUIRES: aarch64-registered-target
 
 // Test new aarch64 intrinsics and types but constrained
 
 #include <arm_neon.h>

clang/test/CodeGen/aarch64-neon-misc-constrained.c

 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon \
 // RUN:  -disable-O0-optnone -emit-llvm -o - %s \
 // RUN: | opt -S -passes=mem2reg | FileCheck --check-prefix=COMMON --check-prefix=COMMONIR --check-prefix=UNCONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon \
 // RUN:  -ffp-exception-behavior=strict \
-// RUN:  -fexperimental-strict-floating-point \
 // RUN:  -disable-O0-optnone -emit-llvm -o - %s \
 // RUN: | opt -S -passes=mem2reg | FileCheck --check-prefix=COMMON --check-prefix=COMMONIR --check-prefix=CONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon \
 // RUN:  -disable-O0-optnone -S -o - %s \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon \
 // RUN:  -ffp-exception-behavior=strict \
-// RUN:  -fexperimental-strict-floating-point \
 // RUN:  -disable-O0-optnone -S -o - %s \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
 
 // REQUIRES: aarch64-registered-target
 
 // Test new aarch64 intrinsics and types but constrained
 
 #include <arm_neon.h>

clang/test/CodeGen/aarch64-neon-scalar-x-indexed-elem-constrained.c

 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-cpu cyclone \
 // RUN: -disable-O0-optnone -emit-llvm -o - %s | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=COMMONIR --check-prefix=UNCONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-cpu cyclone \
 // RUN: -ffp-exception-behavior=strict \
-// RUN: -fexperimental-strict-floating-point \
 // RUN: -disable-O0-optnone -emit-llvm -o - %s | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=COMMONIR --check-prefix=CONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-cpu cyclone \
 // RUN: -disable-O0-optnone -emit-llvm -o - %s | opt -S -passes=mem2reg | llc -o=- - \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-cpu cyclone \
 // RUN: -ffp-exception-behavior=strict \
-// RUN: -fexperimental-strict-floating-point \
 // RUN: -disable-O0-optnone -emit-llvm -o - %s | opt -S -passes=mem2reg | llc -o=- - \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
 
 // REQUIRES: aarch64-registered-target
 
 // Test new aarch64 intrinsics and types but constrained
 
 #include <arm_neon.h>

clang/test/CodeGen/aarch64-strictfp-builtins.c

-// RUN: %clang_cc1 %s -emit-llvm -ffp-exception-behavior=maytrap -fexperimental-strict-floating-point -o - -triple arm64-none-linux-gnu | FileCheck %s
+// RUN: %clang_cc1 %s -emit-llvm -ffp-exception-behavior=maytrap -o - -triple arm64-none-linux-gnu | FileCheck %s
 
 // Test that the constrained intrinsics are picking up the exception
 // metadata from the AST instead of the global default from the command line.
 
 #pragma float_control(except, on)
 
 int printf(const char *, ...);
 

clang/test/CodeGen/aarch64-v8.2a-fp16-intrinsics-constrained.c

 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +fullfp16 \
 // RUN: -S -disable-O0-optnone \
 // RUN: -emit-llvm -o - %s | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefixes=COMMON,COMMONIR,UNCONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +fullfp16 \
 // RUN: -S -disable-O0-optnone \
-// RUN: -ffp-exception-behavior=strict -fexperimental-strict-floating-point -emit-llvm -o - %s | opt -S -passes=mem2reg \
+// RUN: -ffp-exception-behavior=strict -emit-llvm -o - %s | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefixes=COMMON,COMMONIR,CONSTRAINED %s
 
 // REQUIRES: aarch64-registered-target
 
 #include <arm_fp16.h>
 
 // COMMON-LABEL: test_vceqzh_f16
 // UNCONSTRAINED:  [[TMP1:%.*]] = fcmp oeq half %a, 0xH0000

clang/test/CodeGen/aarch64-v8.2a-neon-intrinsics-constrained.c

 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-feature +fullfp16 -target-feature +v8.2a\
 // RUN: -flax-vector-conversions=none -S -disable-O0-optnone -emit-llvm -o - %s \
 // RUN: | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=COMMONIR --check-prefix=UNCONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-feature +fullfp16 -target-feature +v8.2a\
 // RUN: -ffp-exception-behavior=maytrap -DEXCEPT=1 \
-// RUN: -fexperimental-strict-floating-point \
 // RUN: -flax-vector-conversions=none -S -disable-O0-optnone -emit-llvm -o - %s \
 // RUN: | opt -S -passes=mem2reg \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=COMMONIR --check-prefix=CONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-feature +fullfp16 -target-feature +v8.2a\
 // RUN: -flax-vector-conversions=none -S -disable-O0-optnone -emit-llvm -o - %s \
 // RUN: | opt -S -passes=mem2reg | llc -o=- - \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
 // RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -target-feature +fullfp16 -target-feature +v8.2a\
 // RUN: -ffp-exception-behavior=maytrap -DEXCEPT=1 \
-// RUN: -fexperimental-strict-floating-point \
 // RUN: -flax-vector-conversions=none -S -disable-O0-optnone -emit-llvm -o - %s \
 // RUN: | opt -S -passes=mem2reg | llc -o=- - \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
 
 // REQUIRES: aarch64-registered-target
 
 // Test that the constrained intrinsics are picking up the exception
 // metadata from the AST instead of the global default from the command line.

clang/test/CodeGen/arm-neon-directed-rounding-constrained.c

 // RUN: %clang_cc1 -triple thumbv8-linux-gnueabihf -target-cpu cortex-a57 \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | FileCheck -check-prefixes=COMMON,COMMONIR,UNCONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-linux-gnueabihf -target-feature +neon \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | FileCheck -check-prefixes=COMMON,COMMONIR,UNCONSTRAINED %s
 
 // RUN: %clang_cc1 -triple thumbv8-linux-gnueabihf -target-cpu cortex-a57 \
 // RUN:     -ffp-exception-behavior=strict \
 // RUN:     -fexperimental-strict-floating-point \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | FileCheck -check-prefixes=COMMON,COMMONIR,CONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-linux-gnueabihf -target-feature +neon \
 // RUN:     -ffp-exception-behavior=strict \
-// RUN:     -fexperimental-strict-floating-point \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | FileCheck -check-prefixes=COMMON,COMMONIR,CONSTRAINED %s
 
 // RUN: %clang_cc1 -triple thumbv8-linux-gnueabihf -target-cpu cortex-a57 \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | llc -o=- - | FileCheck -check-prefixes=COMMON,CHECK-ASM32 %s
 // RUN: %clang_cc1 -triple arm64-linux-gnueabihf -target-feature +neon \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | llc -o=- - | FileCheck -check-prefixes=COMMON,CHECK-ASM64 %s
 
 // RUN: %clang_cc1 -triple thumbv8-linux-gnueabihf -target-cpu cortex-a57 \
 // RUN:     -ffp-exception-behavior=strict \
 // RUN:     -fexperimental-strict-floating-point \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | llc -o=- - | FileCheck -check-prefixes=COMMON,CHECK-ASM32 %s
 // RUN: %clang_cc1 -triple arm64-linux-gnueabihf -target-feature +neon \
 // RUN:     -ffp-exception-behavior=strict \
-// RUN:     -fexperimental-strict-floating-point \
 // RUN:     -ffreestanding -disable-O0-optnone -emit-llvm %s -o - | \
 // RUN:     opt -S -passes=mem2reg | llc -o=- - | FileCheck -check-prefixes=COMMON,CHECK-ASM64 %s
 
 // REQUIRES: arm-registered-target,aarch64-registered-target
 
 #include <arm_neon.h>
 
 // COMMON-LABEL: test_vrndi_f32

clang/test/CodeGen/arm64-vrnd-constrained.c

 // RUN: %clang_cc1 -triple arm64-apple-ios7 -target-feature +neon -ffreestanding -flax-vector-conversions=none -emit-llvm -o - %s \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=UNCONSTRAINED %s
-// RUN: %clang_cc1 -triple arm64-apple-ios7 -target-feature +neon -ffreestanding -flax-vector-conversions=none -fexperimental-strict-floating-point -ffp-exception-behavior=strict -emit-llvm -o - %s \
+// RUN: %clang_cc1 -triple arm64-apple-ios7 -target-feature +neon -ffreestanding -flax-vector-conversions=none -ffp-exception-behavior=strict -emit-llvm -o - %s \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CONSTRAINED %s
 // RUN: %clang_cc1 -triple arm64-apple-ios7 -target-feature +neon -ffreestanding -flax-vector-conversions=none -emit-llvm -o - %s | llc -o=- - \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
-// RUN: %clang_cc1 -triple arm64-apple-ios7 -target-feature +neon -ffreestanding -flax-vector-conversions=none -fexperimental-strict-floating-point -ffp-exception-behavior=strict -emit-llvm -o - %s | llc -o=- - \
+// RUN: %clang_cc1 -triple arm64-apple-ios7 -target-feature +neon -ffreestanding -flax-vector-conversions=none -ffp-exception-behavior=strict -emit-llvm -o - %s | llc -o=- - \
 // RUN: | FileCheck --check-prefix=COMMON --check-prefix=CHECK-ASM %s
 
 // REQUIRES: aarch64-registered-target
 
 #include <arm_neon.h>
 
 float64x2_t rnd5(float64x2_t a) { return vrndq_f64(a); }
 // COMMON-LABEL: rnd5

clang/test/CodeGen/fp16-ops-strictfp.c

 // REQUIRES: arm-registered-target
 // RUN: %clang_cc1 -ffp-exception-behavior=maytrap -fexperimental-strict-floating-point -emit-llvm -o - -triple arm-none-linux-gnueabi %s | FileCheck %s --check-prefix=NOTNATIVE --check-prefix=CHECK -vv -dump-input=fail
-// RUN: %clang_cc1 -ffp-exception-behavior=maytrap -fexperimental-strict-floating-point -emit-llvm -o - -triple aarch64-none-linux-gnueabi %s | FileCheck %s --check-prefix=NOTNATIVE --check-prefix=CHECK
+// RUN: %clang_cc1 -ffp-exception-behavior=maytrap -emit-llvm -o - -triple aarch64-none-linux-gnueabi %s | FileCheck %s --check-prefix=NOTNATIVE --check-prefix=CHECK
 // RUN: %clang_cc1 -ffp-exception-behavior=maytrap -fexperimental-strict-floating-point -emit-llvm -o - -triple x86_64-linux-gnu %s | FileCheck %s --check-prefix=NOTNATIVE --check-prefix=CHECK
 // RUN: %clang_cc1 -ffp-exception-behavior=maytrap -fexperimental-strict-floating-point -emit-llvm -o - -triple arm-none-linux-gnueabi -fnative-half-type %s \
 // RUN:   | FileCheck %s --check-prefix=NATIVE-HALF --check-prefix=CHECK
-// RUN: %clang_cc1 -ffp-exception-behavior=maytrap -fexperimental-strict-floating-point -emit-llvm -o - -triple aarch64-none-linux-gnueabi -fnative-half-type %s \
+// RUN: %clang_cc1 -ffp-exception-behavior=maytrap -emit-llvm -o - -triple aarch64-none-linux-gnueabi -fnative-half-type %s \
 // RUN:   | FileCheck %s --check-prefix=NATIVE-HALF --check-prefix=CHECK
 //
 // Test that the constrained intrinsics are picking up the exception
 // metadata from the AST instead of the global default from the command line.
 
 #pragma float_control(except, on)
 
 typedef unsigned cond_t;

clang/test/Parser/pragma-fp-warn.c

 
 // RUN: %clang_cc1 -triple wasm32 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
 // RUN: %clang_cc1 -triple thumbv7 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
-// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
+// RUN: %clang_cc1 -DEXPOK -triple aarch64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
 // RUN: %clang_cc1 -DEXPOK -triple x86_64 -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
 // RUN: %clang_cc1 -DEXPOK -triple systemz -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
 // RUN: %clang_cc1 -DEXPOK -triple powerpc -fsyntax-only -Wno-unknown-pragmas -Wignored-pragmas -verify %s
 #ifdef EXPOK
 // expected-no-diagnostics
 #else
 // expected-warning@+4 {{'#pragma float_control' is not supported on this target - ignored}}
 // expected-warning@+5 {{'#pragma FENV_ACCESS' is not supported on this target - ignored}}
 // expected-warning@+6 {{'#pragma FENV_ROUND' is not supported on this target - ignored}}
 #endif
 #pragma float_control(precise, on)
 
 #pragma STDC FENV_ACCESS OFF
 
 #pragma STDC FENV_ROUND FE_DOWNWARD