[PPC64] Fix PR20071 (fctiduz generated for targets lacking that instruction)

PR20071 identifies a problem in PowerPC's fast-isel implementation for
floating-point conversion to integer.  The fctiduz instruction was added in
Power ISA 2.06 (i.e., Power7 and later).  However, this instruction is being
generated regardless of which 64-bit PowerPC target is selected.

The intent is for fast-isel to punt to DAG selection when this instruction is
not available.  This patch implements that change.  For testing purposes, the
existing fast-isel-conversion.ll test adds a RUN line for -mcpu=970 and tests
for the expected code generation.  Additionally, the existing test
fast-isel-conversion-p5.ll was found to be incorrectly expecting the
unavailable instruction to be generated.  I've removed these test variants
since we have adequate coverage in fast-isel-conversion.ll.

llvm-svn: 211627

llvm/lib/Target/PowerPC/PPCFastISel.cpp

@@ -1030,6 +1030,10 @@ bool PPCFastISel::SelectFPToI(const Instruction *I, bool IsSigned) {
   if (DstVT != MVT::i32 && DstVT != MVT::i64)
     return false;
 
+  // If we don't have FCTIDUZ and we need it, punt to SelectionDAG.
+  if (DstVT == MVT::i64 && !IsSigned && !PPCSubTarget->hasFPCVT())
+    return false;
+
   Value *Src = I->getOperand(0);
   Type *SrcTy = Src->getType();
   if (!isTypeLegal(SrcTy, SrcVT))

llvm/test/CodeGen/PowerPC/fast-isel-conversion-p5.ll

@@ -116,18 +116,6 @@ entry:
   ret void
 }
 
-define void @fptoui_float_i64(float %a) nounwind ssp {
-entry:
-; ELF64: fptoui_float_i64
-  %b.addr = alloca i64, align 4
-  %conv = fptoui float %a to i64
-; ELF64: fctiduz
-; ELF64: stfd
-; ELF64: ld
-  store i64 %conv, i64* %b.addr, align 4
-  ret void
-}
-
 define void @fptoui_double_i32(double %a) nounwind ssp {
 entry:
 ; ELF64: fptoui_double_i32
@@ -140,14 +128,3 @@ entry:
   ret void
 }
 
-define void @fptoui_double_i64(double %a) nounwind ssp {
-entry:
-; ELF64: fptoui_double_i64
-  %b.addr = alloca i64, align 8
-  %conv = fptoui double %a to i64
-; ELF64: fctiduz
-; ELF64: stfd
-; ELF64: ld
-  store i64 %conv, i64* %b.addr, align 8
-  ret void
-}

llvm/test/CodeGen/PowerPC/fast-isel-conversion.ll

@@ -1,15 +1,24 @@
 ; RUN: llc < %s -O0 -verify-machineinstrs -fast-isel-abort -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 | FileCheck %s --check-prefix=ELF64
+; RUN: llc < %s -O0 -verify-machineinstrs -mtriple=powerpc64-unknown-linux-gnu -mcpu=970 | FileCheck %s --check-prefix=PPC970
+
+;; Tests for 970 don't use -fast-isel-abort because we intentionally punt
+;; to SelectionDAG in some cases.
 
 ; Test sitofp
 
 define void @sitofp_single_i64(i64 %a, float %b) nounwind ssp {
 entry:
 ; ELF64: sitofp_single_i64
+; PPC970: sitofp_single_i64
   %b.addr = alloca float, align 4
   %conv = sitofp i64 %a to float
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfids
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
+; PPC970: frsp
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -17,11 +26,16 @@ entry:
 define void @sitofp_single_i32(i32 %a, float %b) nounwind ssp {
 entry:
 ; ELF64: sitofp_single_i32
+; PPC970: sitofp_single_i32
   %b.addr = alloca float, align 4
   %conv = sitofp i32 %a to float
 ; ELF64: std
 ; ELF64: lfiwax
 ; ELF64: fcfids
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
+; PPC970: frsp
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -29,12 +43,18 @@ entry:
 define void @sitofp_single_i16(i16 %a, float %b) nounwind ssp {
 entry:
 ; ELF64: sitofp_single_i16
+; PPC970: sitofp_single_i16
   %b.addr = alloca float, align 4
   %conv = sitofp i16 %a to float
 ; ELF64: extsh
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfids
+; PPC970: extsh
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
+; PPC970: frsp
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -42,12 +62,18 @@ entry:
 define void @sitofp_single_i8(i8 %a) nounwind ssp {
 entry:
 ; ELF64: sitofp_single_i8
+; PPC970: sitofp_single_i8
   %b.addr = alloca float, align 4
   %conv = sitofp i8 %a to float
 ; ELF64: extsb
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfids
+; PPC970: extsb
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
+; PPC970: frsp
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -55,11 +81,15 @@ entry:
 define void @sitofp_double_i32(i32 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: sitofp_double_i32
+; PPC970: sitofp_double_i32
   %b.addr = alloca double, align 8
   %conv = sitofp i32 %a to double
 ; ELF64: std
 ; ELF64: lfiwax
 ; ELF64: fcfid
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -67,11 +97,15 @@ entry:
 define void @sitofp_double_i64(i64 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: sitofp_double_i64
+; PPC970: sitofp_double_i64
   %b.addr = alloca double, align 8
   %conv = sitofp i64 %a to double
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfid
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -79,12 +113,17 @@ entry:
 define void @sitofp_double_i16(i16 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: sitofp_double_i16
+; PPC970: sitofp_double_i16
   %b.addr = alloca double, align 8
   %conv = sitofp i16 %a to double
 ; ELF64: extsh
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfid
+; PPC970: extsh
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -92,12 +131,17 @@ entry:
 define void @sitofp_double_i8(i8 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: sitofp_double_i8
+; PPC970: sitofp_double_i8
   %b.addr = alloca double, align 8
   %conv = sitofp i8 %a to double
 ; ELF64: extsb
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfid
+; PPC970: extsb
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -107,11 +151,13 @@ entry:
 define void @uitofp_single_i64(i64 %a, float %b) nounwind ssp {
 entry:
 ; ELF64: uitofp_single_i64
+; PPC970: uitofp_single_i64
   %b.addr = alloca float, align 4
   %conv = uitofp i64 %a to float
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfidus
+; PPC970-NOT: fcfidus
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -119,11 +165,14 @@ entry:
 define void @uitofp_single_i32(i32 %a, float %b) nounwind ssp {
 entry:
 ; ELF64: uitofp_single_i32
+; PPC970: uitofp_single_i32
   %b.addr = alloca float, align 4
   %conv = uitofp i32 %a to float
 ; ELF64: std
 ; ELF64: lfiwzx
 ; ELF64: fcfidus
+; PPC970-NOT: lfiwzx
+; PPC970-NOT: fcfidus
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -131,12 +180,18 @@ entry:
 define void @uitofp_single_i16(i16 %a, float %b) nounwind ssp {
 entry:
 ; ELF64: uitofp_single_i16
+; PPC970: uitofp_single_i16
   %b.addr = alloca float, align 4
   %conv = uitofp i16 %a to float
 ; ELF64: rldicl {{[0-9]+}}, {{[0-9]+}}, 0, 48
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfidus
+; PPC970: rlwinm {{[0-9]+}}, {{[0-9]+}}, 0, 16, 31
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
+; PPC970: frsp
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -144,12 +199,18 @@ entry:
 define void @uitofp_single_i8(i8 %a) nounwind ssp {
 entry:
 ; ELF64: uitofp_single_i8
+; PPC970: uitofp_single_i8
   %b.addr = alloca float, align 4
   %conv = uitofp i8 %a to float
 ; ELF64: rldicl {{[0-9]+}}, {{[0-9]+}}, 0, 56
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfidus
+; PPC970: rlwinm {{[0-9]+}}, {{[0-9]+}}, 0, 24, 31
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
+; PPC970: frsp
   store float %conv, float* %b.addr, align 4
   ret void
 }
@@ -157,11 +218,13 @@ entry:
 define void @uitofp_double_i64(i64 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: uitofp_double_i64
+; PPC970: uitofp_double_i64
   %b.addr = alloca double, align 8
   %conv = uitofp i64 %a to double
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfidu
+; PPC970-NOT: fcfidu
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -169,11 +232,14 @@ entry:
 define void @uitofp_double_i32(i32 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: uitofp_double_i32
+; PPC970: uitofp_double_i32
   %b.addr = alloca double, align 8
   %conv = uitofp i32 %a to double
 ; ELF64: std
 ; ELF64: lfiwzx
 ; ELF64: fcfidu
+; PPC970-NOT: lfiwzx
+; PPC970-NOT: fcfidu
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -181,12 +247,17 @@ entry:
 define void @uitofp_double_i16(i16 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: uitofp_double_i16
+; PPC970: uitofp_double_i16
   %b.addr = alloca double, align 8
   %conv = uitofp i16 %a to double
 ; ELF64: rldicl {{[0-9]+}}, {{[0-9]+}}, 0, 48
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfidu
+; PPC970: rlwinm {{[0-9]+}}, {{[0-9]+}}, 0, 16, 31
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -194,12 +265,17 @@ entry:
 define void @uitofp_double_i8(i8 %a, double %b) nounwind ssp {
 entry:
 ; ELF64: uitofp_double_i8
+; PPC970: uitofp_double_i8
   %b.addr = alloca double, align 8
   %conv = uitofp i8 %a to double
 ; ELF64: rldicl {{[0-9]+}}, {{[0-9]+}}, 0, 56
 ; ELF64: std
 ; ELF64: lfd
 ; ELF64: fcfidu
+; PPC970: rlwinm {{[0-9]+}}, {{[0-9]+}}, 0, 24, 31
+; PPC970: std
+; PPC970: lfd
+; PPC970: fcfid
   store double %conv, double* %b.addr, align 8
   ret void
 }
@@ -209,11 +285,15 @@ entry:
 define void @fptosi_float_i32(float %a) nounwind ssp {
 entry:
 ; ELF64: fptosi_float_i32
+; PPC970: fptosi_float_i32
   %b.addr = alloca i32, align 4
   %conv = fptosi float %a to i32
 ; ELF64: fctiwz
 ; ELF64: stfd
 ; ELF64: lwa
+; PPC970: fctiwz
+; PPC970: stfd
+; PPC970: lwa
   store i32 %conv, i32* %b.addr, align 4
   ret void
 }
@@ -221,11 +301,15 @@ entry:
 define void @fptosi_float_i64(float %a) nounwind ssp {
 entry:
 ; ELF64: fptosi_float_i64
+; PPC970: fptosi_float_i64
   %b.addr = alloca i64, align 4
   %conv = fptosi float %a to i64
 ; ELF64: fctidz
 ; ELF64: stfd
 ; ELF64: ld
+; PPC970: fctidz
+; PPC970: stfd
+; PPC970: ld
   store i64 %conv, i64* %b.addr, align 4
   ret void
 }
@@ -233,11 +317,15 @@ entry:
 define void @fptosi_double_i32(double %a) nounwind ssp {
 entry:
 ; ELF64: fptosi_double_i32
+; PPC970: fptosi_double_i32
   %b.addr = alloca i32, align 8
   %conv = fptosi double %a to i32
 ; ELF64: fctiwz
 ; ELF64: stfd
 ; ELF64: lwa
+; PPC970: fctiwz
+; PPC970: stfd
+; PPC970: lwa
   store i32 %conv, i32* %b.addr, align 8
   ret void
 }
@@ -245,11 +333,15 @@ entry:
 define void @fptosi_double_i64(double %a) nounwind ssp {
 entry:
 ; ELF64: fptosi_double_i64
+; PPC970: fptosi_double_i64
   %b.addr = alloca i64, align 8
   %conv = fptosi double %a to i64
 ; ELF64: fctidz
 ; ELF64: stfd
 ; ELF64: ld
+; PPC970: fctidz
+; PPC970: stfd
+; PPC970: ld
   store i64 %conv, i64* %b.addr, align 8
   ret void
 }
@@ -259,11 +351,15 @@ entry:
 define void @fptoui_float_i32(float %a) nounwind ssp {
 entry:
 ; ELF64: fptoui_float_i32
+; PPC970: fptoui_float_i32
   %b.addr = alloca i32, align 4
   %conv = fptoui float %a to i32
 ; ELF64: fctiwuz
 ; ELF64: stfd
 ; ELF64: lwz
+; PPC970: fctidz
+; PPC970: stfd
+; PPC970: lwz
   store i32 %conv, i32* %b.addr, align 4
   ret void
 }
@@ -271,11 +367,13 @@ entry:
 define void @fptoui_float_i64(float %a) nounwind ssp {
 entry:
 ; ELF64: fptoui_float_i64
+; PPC970: fptoui_float_i64
   %b.addr = alloca i64, align 4
   %conv = fptoui float %a to i64
 ; ELF64: fctiduz
 ; ELF64: stfd
 ; ELF64: ld
+; PPC970-NOT: fctiduz
   store i64 %conv, i64* %b.addr, align 4
   ret void
 }
@@ -283,11 +381,15 @@ entry:
 define void @fptoui_double_i32(double %a) nounwind ssp {
 entry:
 ; ELF64: fptoui_double_i32
+; PPC970: fptoui_double_i32
   %b.addr = alloca i32, align 8
   %conv = fptoui double %a to i32
 ; ELF64: fctiwuz
 ; ELF64: stfd
 ; ELF64: lwz
+; PPC970: fctidz
+; PPC970: stfd
+; PPC970: lwz
   store i32 %conv, i32* %b.addr, align 8
   ret void
 }
@@ -295,11 +397,13 @@ entry:
 define void @fptoui_double_i64(double %a) nounwind ssp {
 entry:
 ; ELF64: fptoui_double_i64
+; PPC970: fptoui_double_i64
   %b.addr = alloca i64, align 8
   %conv = fptoui double %a to i64
 ; ELF64: fctiduz
 ; ELF64: stfd
 ; ELF64: ld
+; PPC970-NOT: fctiduz
   store i64 %conv, i64* %b.addr, align 8
   ret void
 }