[Bug target/62098] New: incorrect code generated by arm gcc

[carrot at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62098

            Bug ID: 62098
           Summary: incorrect code generated by arm  gcc
           Product: gcc
           Version: 4.10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: carrot at google dot com
            Target: arm-unknown-linux-gnueabi

Compile following source code with options -march=armv7-a  -mfpu=vfpv3
-mfloat-abi=softfp -O2 -std=gnu++11

#include <limits>
#include <cmath>

const int kFixedPointDenominator = 64;

float ceilToFloat(int m_value)  {
  float floatValue = static_cast<float>(m_value) / kFixedPointDenominator;
  if (static_cast<int>(floatValue * kFixedPointDenominator) == m_value)
     return floatValue;
  if (floatValue > 0)
     return nextafterf(floatValue, std::numeric_limits<float>::max());
  return nextafterf(floatValue, std::numeric_limits<float>::min());
}


trunk gcc generates:

    fmsr    s15, r0    @ int
    vcvt.f32.s32    s15, s15, #6          // A
    vcvt.s32.f32    s15, s15, #6          // B
    vmov    r3, s15
    cmp    r3, r0
    beq    .L2
    fcmpezs    s15
    fmstat
    ble    .L6
    movw    r1, #65535
    fmrs    r0, s15
    movt    r1, 32639
    b    nextafterf
.L6:
    mov    r1, #8388608
    fmrs    r0, s15
    b    nextafterf
.L2:
    fmrs    r0, s15                       // C
    bx    lr


Instruction C returns the result of instruction B, but the expected return
value is the result of instruction A.

4.9 branch generates the same wrong codes, but 4.8 is correct.