llvm-project/llvm/test/CodeGen/X86/fp-intrinsics.ll

112 lines
3.9 KiB
LLVM

; RUN: llc -O3 -mtriple=x86_64-pc-linux < %s | FileCheck %s
; Verify that constants aren't folded to inexact results when the rounding mode
; is unknown.
;
; double f1() {
; // Because 0.1 cannot be represented exactly, this shouldn't be folded.
; return 1.0/10.0;
; }
;
; CHECK-LABEL: f1
; CHECK: divsd
define double @f1() {
entry:
%div = call double @llvm.experimental.constrained.fdiv.f64(
double 1.000000e+00,
double 1.000000e+01,
metadata !"round.dynamic",
metadata !"fpexcept.strict")
ret double %div
}
; Verify that 'a - 0' isn't simplified to 'a' when the rounding mode is unknown.
;
; double f2(double a) {
; // Because the result of '0 - 0' is negative zero if rounding mode is
; // downward, this shouldn't be simplified.
; return a - 0;
; }
;
; CHECK-LABEL: f2
; CHECK: subsd
define double @f2(double %a) {
entry:
%div = call double @llvm.experimental.constrained.fsub.f64(
double %a,
double 0.000000e+00,
metadata !"round.dynamic",
metadata !"fpexcept.strict")
ret double %div
}
; Verify that '-((-a)*b)' isn't simplified to 'a*b' when the rounding mode is
; unknown.
;
; double f3(double a, double b) {
; // Because the intermediate value involved in this calculation may require
; // rounding, this shouldn't be simplified.
; return -((-a)*b);
; }
;
; CHECK-LABEL: f3:
; CHECK: subsd
; CHECK: mulsd
; CHECK: subsd
define double @f3(double %a, double %b) {
entry:
%sub = call double @llvm.experimental.constrained.fsub.f64(
double -0.000000e+00, double %a,
metadata !"round.dynamic",
metadata !"fpexcept.strict")
%mul = call double @llvm.experimental.constrained.fmul.f64(
double %sub, double %b,
metadata !"round.dynamic",
metadata !"fpexcept.strict")
%ret = call double @llvm.experimental.constrained.fsub.f64(
double -0.000000e+00,
double %mul,
metadata !"round.dynamic",
metadata !"fpexcept.strict")
ret double %ret
}
; Verify that FP operations are not performed speculatively when FP exceptions
; are not being ignored.
;
; double f4(int n, double a) {
; // Because a + 1 may overflow, this should not be simplified.
; if (n > 0)
; return a + 1.0;
; return a;
; }
;
;
; CHECK-LABEL: f4:
; CHECK: testl
; CHECK: jle
; CHECK: addsd
define double @f4(i32 %n, double %a) {
entry:
%cmp = icmp sgt i32 %n, 0
br i1 %cmp, label %if.then, label %if.end
if.then:
%add = call double @llvm.experimental.constrained.fadd.f64(
double 1.000000e+00, double %a,
metadata !"round.dynamic",
metadata !"fpexcept.strict")
br label %if.end
if.end:
%a.0 = phi double [%add, %if.then], [ %a, %entry ]
ret double %a.0
}
@llvm.fp.env = thread_local global i8 zeroinitializer, section "llvm.metadata"
declare double @llvm.experimental.constrained.fdiv.f64(double, double, metadata, metadata)
declare double @llvm.experimental.constrained.fmul.f64(double, double, metadata, metadata)
declare double @llvm.experimental.constrained.fadd.f64(double, double, metadata, metadata)
declare double @llvm.experimental.constrained.fsub.f64(double, double, metadata, metadata)