[SystemZ] Improve spilling of LGDR and LDGR

If the source of these instructions is spilled we should load the destination.
If the destination is spilled we should store the source.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186147 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 288 insertions, 0 deletions

diff --git a/test/CodeGen/SystemZ/fp-move-02.ll b/test/CodeGen/SystemZ/fp-move-02.ll
index f828b2d1ad..165d025e3b 100644
--- a/test/CodeGen/SystemZ/fp-move-02.ll
+++ b/test/CodeGen/SystemZ/fp-move-02.ll
@@ -2,6 +2,11 @@
 ;
 ; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
 
+declare i64 @foo()
+declare double @bar()
+@dptr = external global double
+@iptr = external global i64
+
 ; Test 32-bit moves from GPRs to FPRs.  The GPR must be moved into the high
 ; 32 bits of the FPR.
 define float @f1(i32 %a) {
@@ -102,3 +107,286 @@ define void @f9(fp128 *%a, i128 *%b) {
   ret void
 }
 
+; Test cases where the destination of an LGDR needs to be spilled.
+; We shouldn't have any integer stack stores or floating-point loads.
+define void @f10(double %extra) {
+; CHECK: f10:
+; CHECK: dptr
+; CHECK-NOT: stg {{.*}}(%r15)
+; CHECK: %loop
+; CHECK-NOT: ld {{.*}}(%r15)
+; CHECK: %exit
+; CHECK: br %r14
+entry:
+  %double0 = load volatile double *@dptr
+  %biased0 = fadd double %double0, %extra
+  %int0 = bitcast double %biased0 to i64
+  %double1 = load volatile double *@dptr
+  %biased1 = fadd double %double1, %extra
+  %int1 = bitcast double %biased1 to i64
+  %double2 = load volatile double *@dptr
+  %biased2 = fadd double %double2, %extra
+  %int2 = bitcast double %biased2 to i64
+  %double3 = load volatile double *@dptr
+  %biased3 = fadd double %double3, %extra
+  %int3 = bitcast double %biased3 to i64
+  %double4 = load volatile double *@dptr
+  %biased4 = fadd double %double4, %extra
+  %int4 = bitcast double %biased4 to i64
+  %double5 = load volatile double *@dptr
+  %biased5 = fadd double %double5, %extra
+  %int5 = bitcast double %biased5 to i64
+  %double6 = load volatile double *@dptr
+  %biased6 = fadd double %double6, %extra
+  %int6 = bitcast double %biased6 to i64
+  %double7 = load volatile double *@dptr
+  %biased7 = fadd double %double7, %extra
+  %int7 = bitcast double %biased7 to i64
+  %double8 = load volatile double *@dptr
+  %biased8 = fadd double %double8, %extra
+  %int8 = bitcast double %biased8 to i64
+  %double9 = load volatile double *@dptr
+  %biased9 = fadd double %double9, %extra
+  %int9 = bitcast double %biased9 to i64
+  br label %loop
+
+loop:
+  %start = call i64 @foo()
+  %or0 = or i64 %start, %int0
+  %or1 = or i64 %or0, %int1
+  %or2 = or i64 %or1, %int2
+  %or3 = or i64 %or2, %int3
+  %or4 = or i64 %or3, %int4
+  %or5 = or i64 %or4, %int5
+  %or6 = or i64 %or5, %int6
+  %or7 = or i64 %or6, %int7
+  %or8 = or i64 %or7, %int8
+  %or9 = or i64 %or8, %int9
+  store i64 %or9, i64 *@iptr
+  %cont = icmp ne i64 %start, 1
+  br i1 %cont, label %loop, label %exit
+
+exit:
+  ret void
+}
+
+; ...likewise LDGR, with the requirements the other way around.
+define void @f11(i64 %mask) {
+; CHECK: f11:
+; CHECK: iptr
+; CHECK-NOT: std {{.*}}(%r15)
+; CHECK: %loop
+; CHECK-NOT: lg {{.*}}(%r15)
+; CHECK: %exit
+; CHECK: br %r14
+entry:
+  %int0 = load volatile i64 *@iptr
+  %masked0 = and i64 %int0, %mask
+  %double0 = bitcast i64 %masked0 to double
+  %int1 = load volatile i64 *@iptr
+  %masked1 = and i64 %int1, %mask
+  %double1 = bitcast i64 %masked1 to double
+  %int2 = load volatile i64 *@iptr
+  %masked2 = and i64 %int2, %mask
+  %double2 = bitcast i64 %masked2 to double
+  %int3 = load volatile i64 *@iptr
+  %masked3 = and i64 %int3, %mask
+  %double3 = bitcast i64 %masked3 to double
+  %int4 = load volatile i64 *@iptr
+  %masked4 = and i64 %int4, %mask
+  %double4 = bitcast i64 %masked4 to double
+  %int5 = load volatile i64 *@iptr
+  %masked5 = and i64 %int5, %mask
+  %double5 = bitcast i64 %masked5 to double
+  %int6 = load volatile i64 *@iptr
+  %masked6 = and i64 %int6, %mask
+  %double6 = bitcast i64 %masked6 to double
+  %int7 = load volatile i64 *@iptr
+  %masked7 = and i64 %int7, %mask
+  %double7 = bitcast i64 %masked7 to double
+  %int8 = load volatile i64 *@iptr
+  %masked8 = and i64 %int8, %mask
+  %double8 = bitcast i64 %masked8 to double
+  %int9 = load volatile i64 *@iptr
+  %masked9 = and i64 %int9, %mask
+  %double9 = bitcast i64 %masked9 to double
+  br label %loop
+
+loop:
+  %start = call double @bar()
+  %add0 = fadd double %start, %double0
+  %add1 = fadd double %add0, %double1
+  %add2 = fadd double %add1, %double2
+  %add3 = fadd double %add2, %double3
+  %add4 = fadd double %add3, %double4
+  %add5 = fadd double %add4, %double5
+  %add6 = fadd double %add5, %double6
+  %add7 = fadd double %add6, %double7
+  %add8 = fadd double %add7, %double8
+  %add9 = fadd double %add8, %double9
+  store double %add9, double *@dptr
+  %cont = fcmp one double %start, 1.0
+  br i1 %cont, label %loop, label %exit
+
+exit:
+  ret void
+}
+
+; Test cases where the source of an LDGR needs to be spilled.
+; We shouldn't have any integer stack stores or floating-point loads.
+define void @f12() {
+; CHECK: f12:
+; CHECK: %loop
+; CHECK-NOT: std {{.*}}(%r15)
+; CHECK: %exit
+; CHECK: foo@PLT
+; CHECK-NOT: lg {{.*}}(%r15)
+; CHECK: foo@PLT
+; CHECK: br %r14
+entry:
+  br label %loop
+
+loop:
+  %int0 = phi i64 [ 0, %entry ], [ %add0, %loop ]
+  %int1 = phi i64 [ 0, %entry ], [ %add1, %loop ]
+  %int2 = phi i64 [ 0, %entry ], [ %add2, %loop ]
+  %int3 = phi i64 [ 0, %entry ], [ %add3, %loop ]
+  %int4 = phi i64 [ 0, %entry ], [ %add4, %loop ]
+  %int5 = phi i64 [ 0, %entry ], [ %add5, %loop ]
+  %int6 = phi i64 [ 0, %entry ], [ %add6, %loop ]
+  %int7 = phi i64 [ 0, %entry ], [ %add7, %loop ]
+  %int8 = phi i64 [ 0, %entry ], [ %add8, %loop ]
+  %int9 = phi i64 [ 0, %entry ], [ %add9, %loop ]
+
+  %bias = call i64 @foo()
+  %add0 = add i64 %int0, %bias
+  %add1 = add i64 %int1, %bias
+  %add2 = add i64 %int2, %bias
+  %add3 = add i64 %int3, %bias
+  %add4 = add i64 %int4, %bias
+  %add5 = add i64 %int5, %bias
+  %add6 = add i64 %int6, %bias
+  %add7 = add i64 %int7, %bias
+  %add8 = add i64 %int8, %bias
+  %add9 = add i64 %int9, %bias
+  %cont = icmp ne i64 %bias, 1
+  br i1 %cont, label %loop, label %exit
+
+exit:
+  %unused1 = call i64 @foo()
+  %factor = load volatile double *@dptr
+
+  %conv0 = bitcast i64 %add0 to double
+  %mul0 = fmul double %conv0, %factor
+  store volatile double %mul0, double *@dptr
+  %conv1 = bitcast i64 %add1 to double
+  %mul1 = fmul double %conv1, %factor
+  store volatile double %mul1, double *@dptr
+  %conv2 = bitcast i64 %add2 to double
+  %mul2 = fmul double %conv2, %factor
+  store volatile double %mul2, double *@dptr
+  %conv3 = bitcast i64 %add3 to double
+  %mul3 = fmul double %conv3, %factor
+  store volatile double %mul3, double *@dptr
+  %conv4 = bitcast i64 %add4 to double
+  %mul4 = fmul double %conv4, %factor
+  store volatile double %mul4, double *@dptr
+  %conv5 = bitcast i64 %add5 to double
+  %mul5 = fmul double %conv5, %factor
+  store volatile double %mul5, double *@dptr
+  %conv6 = bitcast i64 %add6 to double
+  %mul6 = fmul double %conv6, %factor
+  store volatile double %mul6, double *@dptr
+  %conv7 = bitcast i64 %add7 to double
+  %mul7 = fmul double %conv7, %factor
+  store volatile double %mul7, double *@dptr
+  %conv8 = bitcast i64 %add8 to double
+  %mul8 = fmul double %conv8, %factor
+  store volatile double %mul8, double *@dptr
+  %conv9 = bitcast i64 %add9 to double
+  %mul9 = fmul double %conv9, %factor
+  store volatile double %mul9, double *@dptr
+
+  %unused2 = call i64 @foo()
+
+  ret void
+}
+
+; ...likewise LGDR, with the requirements the other way around.
+define void @f13() {
+; CHECK: f13:
+; CHECK: %loop
+; CHECK-NOT: stg {{.*}}(%r15)
+; CHECK: %exit
+; CHECK: foo@PLT
+; CHECK-NOT: ld {{.*}}(%r15)
+; CHECK: foo@PLT
+; CHECK: br %r14
+entry:
+  br label %loop
+
+loop:
+  %double0 = phi double [ 1.0, %entry ], [ %mul0, %loop ]
+  %double1 = phi double [ 1.0, %entry ], [ %mul1, %loop ]
+  %double2 = phi double [ 1.0, %entry ], [ %mul2, %loop ]
+  %double3 = phi double [ 1.0, %entry ], [ %mul3, %loop ]
+  %double4 = phi double [ 1.0, %entry ], [ %mul4, %loop ]
+  %double5 = phi double [ 1.0, %entry ], [ %mul5, %loop ]
+  %double6 = phi double [ 1.0, %entry ], [ %mul6, %loop ]
+  %double7 = phi double [ 1.0, %entry ], [ %mul7, %loop ]
+  %double8 = phi double [ 1.0, %entry ], [ %mul8, %loop ]
+  %double9 = phi double [ 1.0, %entry ], [ %mul9, %loop ]
+
+  %factor = call double @bar()
+  %mul0 = fmul double %double0, %factor
+  %mul1 = fmul double %double1, %factor
+  %mul2 = fmul double %double2, %factor
+  %mul3 = fmul double %double3, %factor
+  %mul4 = fmul double %double4, %factor
+  %mul5 = fmul double %double5, %factor
+  %mul6 = fmul double %double6, %factor
+  %mul7 = fmul double %double7, %factor
+  %mul8 = fmul double %double8, %factor
+  %mul9 = fmul double %double9, %factor
+  %cont = fcmp one double %factor, 1.0
+  br i1 %cont, label %loop, label %exit
+
+exit:
+  %unused1 = call i64 @foo()
+  %bias = load volatile i64 *@iptr
+
+  %conv0 = bitcast double %mul0 to i64
+  %add0 = add i64 %conv0, %bias
+  store volatile i64 %add0, i64 *@iptr
+  %conv1 = bitcast double %mul1 to i64
+  %add1 = add i64 %conv1, %bias
+  store volatile i64 %add1, i64 *@iptr
+  %conv2 = bitcast double %mul2 to i64
+  %add2 = add i64 %conv2, %bias
+  store volatile i64 %add2, i64 *@iptr
+  %conv3 = bitcast double %mul3 to i64
+  %add3 = add i64 %conv3, %bias
+  store volatile i64 %add3, i64 *@iptr
+  %conv4 = bitcast double %mul4 to i64
+  %add4 = add i64 %conv4, %bias
+  store volatile i64 %add4, i64 *@iptr
+  %conv5 = bitcast double %mul5 to i64
+  %add5 = add i64 %conv5, %bias
+  store volatile i64 %add5, i64 *@iptr
+  %conv6 = bitcast double %mul6 to i64
+  %add6 = add i64 %conv6, %bias
+  store volatile i64 %add6, i64 *@iptr
+  %conv7 = bitcast double %mul7 to i64
+  %add7 = add i64 %conv7, %bias
+  store volatile i64 %add7, i64 *@iptr
+  %conv8 = bitcast double %mul8 to i64
+  %add8 = add i64 %conv8, %bias
+  store volatile i64 %add8, i64 *@iptr
+  %conv9 = bitcast double %mul9 to i64
+  %add9 = add i64 %conv9, %bias
+  store volatile i64 %add9, i64 *@iptr
+
+  %unused2 = call i64 @foo()
+
+  ret void
+}