[SPE] Disable strict-fp for SPE by default

[qiucf]

Summary

As discussed in PR50385, strict-fp on PowerPC SPE has not been handled well. This patch disables it by default for SPE.

[nemanjai]

LGTM. Thanks.

clang/lib/Basic/Targets/PPC.cpp

if (Feature == "+altivec") {
       HasP9Vector = true;
     } else if (Feature == "+power10-vector") {
       HasP10Vector = true;
     } else if (Feature == "+pcrelative-memops") {
       HasPCRelativeMemops = true;
     } else if (Feature == "+prefix-instrs") {
       HasPrefixInstrs = true;
     } else if (Feature == "+spe" || Feature == "+efpu2") {
+      HasStrictFP = false;
       HasSPE = true;
       LongDoubleWidth = LongDoubleAlign = 64;
       LongDoubleFormat = &llvm::APFloat::IEEEdouble();
     } else if (Feature == "-hard-float") {
       FloatABI = SoftFloat;
     } else if (Feature == "+paired-vector-memops") {
       PairedVectorMemops = true;
     } else if (Feature == "+mma") {

clang/test/CodeGen/builtins-ppc-fpconstrained.c

 // REQUIRES: powerpc-registered-target
 // RUN: %clang_cc1 -triple powerpc64le-gnu-linux -target-feature +vsx \
 // RUN: -emit-llvm %s -o - | FileCheck --check-prefix=CHECK-UNCONSTRAINED %s
 // RUN: %clang_cc1 -triple powerpc64le-gnu-linux -target-feature +vsx \
 // RUN:  -ffp-exception-behavior=strict -emit-llvm %s -o - | FileCheck \
 // RUN: --check-prefix=CHECK-CONSTRAINED -vv %s
 // RUN: %clang_cc1 -triple powerpc64le-gnu-linux -target-feature +vsx \
 // RUN: -fallow-half-arguments-and-returns -S -o - %s | \
 // RUN: FileCheck --check-prefix=CHECK-ASM --check-prefix=NOT-FIXME-CHECK  %s
 // RUN: %clang_cc1 -triple powerpc64le-gnu-linux -target-feature +vsx \
 // RUN: -fallow-half-arguments-and-returns -S -ffp-exception-behavior=strict \
 // RUN: -o - %s | FileCheck --check-prefix=CHECK-ASM \
 // RUN: --check-prefix=FIXME-CHECK  %s
+// RUN: %clang_cc1 -triple powerpcspe -S -ffp-exception-behavior=strict \
+// RUN: -target-feature +spe -fexperimental-strict-floating-point -emit-llvm \
+// RUN: %s -o - | FileCheck --check-prefix=CHECK-CONSTRAINED %s
 
 typedef __attribute__((vector_size(4 * sizeof(float)))) float vec_float;
 typedef __attribute__((vector_size(2 * sizeof(double)))) double vec_double;
 
 volatile vec_double vd;
 volatile vec_float vf;
 
 void test_float(void) {