[X86] Add AVX512 support to X86FastISel::X86SelectFPExt and X86FastISel::X86SelectFPTrunc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316856 91177308-0d34-0410-b5e6-96231b3b80d8

Author: topperc

lib/Target/X86/X86FastISel.cpp

@@ -2473,9 +2473,13 @@ bool X86FastISel::X86SelectFPExtOrFPTrunc(const Instruction *I,
 bool X86FastISel::X86SelectFPExt(const Instruction *I) {
   if (X86ScalarSSEf64 && I->getType()->isDoubleTy() &&
       I->getOperand(0)->getType()->isFloatTy()) {
+    bool HasAVX512 = Subtarget->hasAVX512();
     // fpext from float to double.
-    unsigned Opc = Subtarget->hasAVX() ? X86::VCVTSS2SDrr : X86::CVTSS2SDrr;
-    return X86SelectFPExtOrFPTrunc(I, Opc, &X86::FR64RegClass);
+    unsigned Opc =
+        HasAVX512 ? X86::VCVTSS2SDZrr
+                  : Subtarget->hasAVX() ? X86::VCVTSS2SDrr : X86::CVTSS2SDrr;
+    return X86SelectFPExtOrFPTrunc(
+        I, Opc, HasAVX512 ? &X86::FR64XRegClass : &X86::FR64RegClass);
   }
 
   return false;
@@ -2484,9 +2488,13 @@ bool X86FastISel::X86SelectFPExt(const Instruction *I) {
 bool X86FastISel::X86SelectFPTrunc(const Instruction *I) {
   if (X86ScalarSSEf64 && I->getType()->isFloatTy() &&
       I->getOperand(0)->getType()->isDoubleTy()) {
+    bool HasAVX512 = Subtarget->hasAVX512();
     // fptrunc from double to float.
-    unsigned Opc = Subtarget->hasAVX() ? X86::VCVTSD2SSrr : X86::CVTSD2SSrr;
-    return X86SelectFPExtOrFPTrunc(I, Opc, &X86::FR32RegClass);
+    unsigned Opc =
+        HasAVX512 ? X86::VCVTSD2SSZrr
+                  : Subtarget->hasAVX() ? X86::VCVTSD2SSrr : X86::CVTSD2SSrr;
+    return X86SelectFPExtOrFPTrunc(
+        I, Opc, HasAVX512 ? &X86::FR32XRegClass : &X86::FR32RegClass);
   }
 
   return false;

test/CodeGen/X86/fast-isel-fptrunc-fpext.ll

@@ -1,6 +1,7 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse2 -fast-isel -fast-isel-abort=1 | FileCheck %s --check-prefix=ALL --check-prefix=SSE
 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx -fast-isel -fast-isel-abort=1 | FileCheck %s --check-prefix=ALL --check-prefix=AVX
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512f -fast-isel -fast-isel-abort=1 | FileCheck %s --check-prefix=ALL --check-prefix=AVX
 ;
 ; Verify that fast-isel doesn't select legacy SSE instructions on targets that
 ; feature AVX.