llvm-6502/test/CodeGen/PowerPC/floatPSA.ll
Bill Schmidt 11729224bf [PowerPC] Disable fast-isel for existing -O0 tests for PowerPC.
This is a preliminary patch for fast instruction selection on
PowerPC.  Code generation can differ between DAG isel and fast isel.
Existing tests that specify -O0 were written to expect DAG isel.  Make
this explicit by adding -fast-isel=false to the tests.

In some cases specifying -fast-isel=false produces different code even
when there isn't a fast instruction selector specified.  This is
because TM.Options.EnableFastISel = 1 at -O0 whether or not a FastISel
object exists.  Thus disabling fast isel can actually produce less
conservative code.  Because of this, some of the expected code
generation in the -O0 tests needs to be adjusted.

In particular, handling of function arguments is less conservative
with -fast-isel=false (see isOnlyUsedInEntryBlock() in
SelectionDAGBuilder.cpp).  This results in fewer stack accesses and,
in some cases, reduced stack size as uselessly loaded values are no
longer stored back to spill locations in the stack.

No functional change with this patch; test case adjustments only.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183939 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-13 20:23:34 +00:00

98 lines
3.6 KiB
LLVM

; RUN: llc -O0 -mtriple=powerpc64-unknown-linux-gnu -fast-isel=false < %s | FileCheck %s
; This verifies that single-precision floating point values that can't
; be passed in registers are stored in the rightmost word of the parameter
; save area slot. There are 13 architected floating-point registers, so
; the 14th is passed in storage. The address of the 14th argument is
; 48 (fixed size of the linkage area) + 13 * 8 (first 13 args) + 4
; (offset to second word) = 156.
define float @bar(float %a, float %b, float %c, float %d, float %e, float %f, float %g, float %h, float %i, float %j, float %k, float %l, float %m, float %n) nounwind {
entry:
%a.addr = alloca float, align 4
%b.addr = alloca float, align 4
%c.addr = alloca float, align 4
%d.addr = alloca float, align 4
%e.addr = alloca float, align 4
%f.addr = alloca float, align 4
%g.addr = alloca float, align 4
%h.addr = alloca float, align 4
%i.addr = alloca float, align 4
%j.addr = alloca float, align 4
%k.addr = alloca float, align 4
%l.addr = alloca float, align 4
%m.addr = alloca float, align 4
%n.addr = alloca float, align 4
store float %a, float* %a.addr, align 4
store float %b, float* %b.addr, align 4
store float %c, float* %c.addr, align 4
store float %d, float* %d.addr, align 4
store float %e, float* %e.addr, align 4
store float %f, float* %f.addr, align 4
store float %g, float* %g.addr, align 4
store float %h, float* %h.addr, align 4
store float %i, float* %i.addr, align 4
store float %j, float* %j.addr, align 4
store float %k, float* %k.addr, align 4
store float %l, float* %l.addr, align 4
store float %m, float* %m.addr, align 4
store float %n, float* %n.addr, align 4
%0 = load float* %n.addr, align 4
ret float %0
}
; CHECK: lfs {{[0-9]+}}, 156(1)
define float @foo() nounwind {
entry:
%a = alloca float, align 4
%b = alloca float, align 4
%c = alloca float, align 4
%d = alloca float, align 4
%e = alloca float, align 4
%f = alloca float, align 4
%g = alloca float, align 4
%h = alloca float, align 4
%i = alloca float, align 4
%j = alloca float, align 4
%k = alloca float, align 4
%l = alloca float, align 4
%m = alloca float, align 4
%n = alloca float, align 4
store float 1.000000e+00, float* %a, align 4
store float 2.000000e+00, float* %b, align 4
store float 3.000000e+00, float* %c, align 4
store float 4.000000e+00, float* %d, align 4
store float 5.000000e+00, float* %e, align 4
store float 6.000000e+00, float* %f, align 4
store float 7.000000e+00, float* %g, align 4
store float 8.000000e+00, float* %h, align 4
store float 9.000000e+00, float* %i, align 4
store float 1.000000e+01, float* %j, align 4
store float 1.100000e+01, float* %k, align 4
store float 1.200000e+01, float* %l, align 4
store float 1.300000e+01, float* %m, align 4
store float 1.400000e+01, float* %n, align 4
%0 = load float* %a, align 4
%1 = load float* %b, align 4
%2 = load float* %c, align 4
%3 = load float* %d, align 4
%4 = load float* %e, align 4
%5 = load float* %f, align 4
%6 = load float* %g, align 4
%7 = load float* %h, align 4
%8 = load float* %i, align 4
%9 = load float* %j, align 4
%10 = load float* %k, align 4
%11 = load float* %l, align 4
%12 = load float* %m, align 4
%13 = load float* %n, align 4
%call = call float @bar(float %0, float %1, float %2, float %3, float %4, float %5, float %6, float %7, float %8, float %9, float %10, float %11, float %12, float %13)
ret float %call
}
; Note that stw is used instead of stfs because the value is a simple
; constant that can be created with a load-immediate in a GPR.
; CHECK: stw {{[0-9]+}}, 156(1)